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Skills for Work:Energy

Intermediate 2

September 2008

Conventional EnergyTechnologies and the Grid

Support Material

Energy: Conventional Energy Technologies and the Grid – (Intermediate 2)

Scottish Further Education Unit 3

Acknowledgements SFEU is grateful to the subject specialists in Scotland’s Colleges and other agencies and industry bodies who have been involved in the writing of this and other support materials in the Skills for Work series. SFEU is also grateful for the contribution of the Scottish Qualifications Authority in the compilation of these materials, specifically for its permission to reproduce extracts from Course and Unit Specifications and the Skills for Work Rationale. We are also grateful to the following for permission to use images Ryan James King Gary Honeyman Scottish Gazetteer Scottish and Southern Energy RS Components Voith-Siemens The National Grid Carnegie College © Scottish Further Education Unit 2008 Scottish Further Education Unit (SFEU) Argyll Court Castle Business Park Stirling FK9 4TY website: www.sfeu.ac.uk e-mail: [email protected] SFEU is a Registered Scottish Charity No. SC021876 and a Company Limited by Guarantee No. SC143514 VAT No. 617148346

These support materials were produced with assistance from the European Social Fund.



Energy (Intermediate 2) Energy: Conventional Energy Technologies and the Grid F3FV 11 Introduction These notes are provided to support teachers and lecturers presenting the Scottish Qualifications Authority Course F3FV 11, Energy: Conventional Energy Technologies and the Grid (Intermediate 2). Copyright for this pack is held by the Scottish Further Education Unit (SFEU). However, teachers and lecturers have permission to use the pack and reproduce items from the pack provided that this is to support teaching and learning processes and that no profit is made from such use. If reproduced in part, the source should be acknowledged. Enquiries relating to this support pack or issues relating to copyright should be addressed to: Marketing Officer - Communications The Scottish Further Education Unit Argyll Court Castle Business Park Stirling FK9 4TY Website: www.sfeu.ac.uk Further information regarding this Unit including Unit Specifications, National Assessment Bank materials, Centre Approval and certification can be obtained from: The Scottish Qualifications Authority Optima Building 58 Robertson Street Glasgow G2 8DQ Website: www.sqa.org.uk



Class Sets Class sets of this pack may be purchased direct from the printer. Costs are dependent on the size of the pack and the number of copies. Please contact: Elanders Hindson Merlin Way New York Business Park North Tyneside NE27 0QG Tel: 0191 280 0400 e-mail: [email protected] Disclaimer Whilst every effort has been made to ensure the accuracy of this support pack, teachers and lecturers should satisfy themselves that the information passed to candidates is accurate and in accordance with the current SQA arrangements documents. SFEU will accept no responsibility for any consequences deriving either directly or indirectly from the use of this pack.



Contents

How to Use this Pack 9

Reference Section 10

What are Skills for Work Courses all about? 11

The Course in Energy (Intermediate 2) 14

Unit Outcomes, PCs and Evidence Requirements 17

Employability Skills Profile 20

Careers Scotland Support 21

Tutor Support Section 22

Learning and Teaching with Under 16s 23

General Guidance on Unit Delivery 27

Unit Induction 27

Learning and Teaching Approach 27

Resources 30

Signposting of Employability Skills 34

Generating Evidence and Assessment Opportunities for Employability Skills 35

Suggested Answers to Student Activities 40

Student Support Section 44

Tutor Note on Student Activities 45

Welcome to Energy: Conventional Technology and the Grid 46

Renewable and Non-Renewable Energy: Carbon Footprint 48

Energy: Loss, Efficiency and Consumption 50

Power Stations 58

Oil Fired Power Stations 58

Coal Fired Power Stations 61

Gas Fired Power Stations 64

Nuclear Power Stations 68

Hydro Power Stations 76

Hydro Power Engineers 77



Turbines 79

The National Grid 85

Substations 91

Transformers 91

Busbars 93

Switchgear 95

The Future of Electricity Supplies 99

Glossary of Terms 101

Appendix 103



How to Use this Pack None of the material in this pack is mandatory. Rather, it is intended as a guide and an aid to delivery of the Unit and aims to provide centres with a flexible set of materials and activities which can be selected, adapted and used in whatever way suits individual circumstances. It may also be a useful supplement to tried and tested materials that you have developed yourself. The pack is available on the SFEU website in Word format to enable you to customise it to suit your own needs. The pack is organised into several sections: The Reference Section provides information on the rationale for, and ethos behind, Skills for Work courses, the course rationale, the Unit Outcomes and evidence requirements and the Employability Skills Profile for Skills for Work Energy: (Intermediate 2), showing where the specified employability skills and attitudes can be evidenced and assessed throughout the Course and in this unit. The Tutor Support Section contains a suggested approach to teaching the Unit, advice on learning and teaching with under-16s, guidance on unit induction, unit delivery and advice on integrating the development of employability skills throughout the unit. Industrial visits and lectures from external industry experts would help enhance the teaching process. Finally, this section suggests resources which may be useful for tutors and students. The Student Support Section contains guidance and instruction on how students should approach the methods available to seek out information for investigations. The student notes provided do not constitute comprehensive coverage of conventional technologies and the grid because it is expected that the students will research and investigate the topics themselves. However, industry specific websites are suggested. Internet access will be required to complete this unit. The investigation brief and worksheets are contained in the NAB for the Unit. You may wish to place material from the student notes on your own Intranet by downloading this pack from the Skills for Work section of the SFEU website http://www.sfeu.ac.uk/skills_for_work Activities are identified with the symbol:



Reference Section



What are Skills for Work Courses all about? Skills for Work Courses are designed to help candidates to develop:

• skills and knowledge in a broad vocational area

• Core Skills

• an understanding of the workplace

• positive attitudes to learning

• skills and attitudes for employability. A key feature of these Courses is the emphasis on experiential learning. This means learning through practical experience and learning by reflecting on experience. Learning through practical experience Teaching/learning programmes should include some or all of the following:

• learning in real or simulated workplace settings

• learning through role play activities in vocational contexts

• carrying out case study work

• planning and carrying out practical tasks and assignments. Learning through reflecting at all stages of the experience Teaching/learning programmes should include some or all of the following:

• preparing and planning for the experience

• taking stock throughout the experience - reviewing and adapting as necessary

• reflecting after the activity has been completed - evaluating, self-assessing and identifying learning points.

The Skills for Work Courses are also designed to provide candidates with opportunities for developing Core Skills and enhancing skills and attitudes for employability.



Core Skills The five Core Skills are:

• Communication

• Numeracy

• Information Technology

• Problem Solving

• Working with Others Employability The skills and attitudes for employability, including self-employment, are outlined below:

• generic skills/attitudes valued by employers

• understanding of the workplace and the employee’s responsibilities, for example timekeeping, appearance, customer care

• self-evaluation skills

• positive attitude to learning

• flexible approaches to solving problems

• adaptability and positive attitude to change

• confidence to set goals, reflect and learn from experience.

• specific vocational skills/knowledge

• Course Specifications highlight the links to National Occupational Standards in the vocational area and identify progression opportunities

Opportunities for developing these skills and attitudes are highlighted in each of the Course and Unit Specifications. These opportunities include giving young people direct access to workplace experiences or, through partnership arrangements, providing different learning environments and experiences which simulate aspects of the workplace. These experiences might include visits, visiting speakers, role play and other practical activities.



A Curriculum for Excellence (Scottish Executive 2004) identifies aspirations for every young person. These are that they should become:

• successful learners

• confident individuals

• responsible citizens

• effective contributors. The learning environments, the focus on experiential learning and the opportunities to develop employability and Core Skills in these Courses contribute to meeting these aspirations.



The Course in Energy (Intermediate 2) Course Rationale This Course is intended to equip candidates with the necessary knowledge and skills which will enhance their prospects for employment in the wide range of opportunities within energy sectors. The Course will allow candidates to develop a range of employability skills which are of particular relevance to energy industries. Core Skills of Information Technology and Problem Solving will also be developed throughout the Course where opportunities arise. The Course will offer a variety of approaches to learning and teaching and will include a strong element of experiential learning. It is intended that some of the Course will be delivered and assessed in a different learning environment to that of the school through a partnership arrangement with a college, training provider, or employer. There are many technologies used in the production of energy and this course has been designed to contain both an electrical generation practical/skills element using wind turbines and a heat generation practical/skills element using solar panels. These elements were selected to ensure candidates received a range of skills using different technologies that are involved in the generation of energy. Other systems used to generate energy from both the traditional/conventional and renewable systems will be discussed and evaluated during the Course. The primary target group for this Course is school candidates in S3 and S4. However, the Course is also suitable for S5/S6 candidates and adult candidates who are seeking to enhance their employability and vocational skills in the energy sector. The general aims of the Course are to: • widen participation in vocationally-related learning for 14–16 year olds

• allow candidates to experience vocationally-related learning

• provide candidates with a broad introduction to the energy sector

• allow candidates the opportunity to develop skills relevant to the micro-generation energy sector

• develop the candidates’ engineering skills

• encourage candidates to evaluate the impact of energy generation on the environment

• encourage candidates to foster a good work ethic, including timekeeping, a positive attitude and other relevant employability skills

• provide opportunities to develop a range of Core Skills in a realistic context

• encourage candidates to take charge of their own learning and development

• provide a range of teaching, learning, and assessment styles to motivate candidates to achieve their full potential



• facilitate progression to further education and/or training In particular, the specific aims of the Course are to:

• encourage candidates to consider a career in the energy sector

• develop an awareness of the role of conventional and renewable energy systems in the UK

• develop an awareness of what opportunities there may be within the sector in terms of the types and range of career options

• provide candidates with knowledge and skills which are directly relevant to employment within the energy sector, eg. solar hot water and wind turbines

• provide opportunities for the personal development of skills and attitudes which will improve the candidates’ employment potential within the energy sector

• develop the candidates’ awareness of their individual strengths and weaknesses in relation to the requirements of the sector, and to reflect on how this affects their employability potential

• raise awareness of the impact of the energy sector on the environment

• raise awareness of the responsibilities of the energy industry with regard to the environment

Rationale for Course content The production and use of energy is important in everyone’s life and is also an important area of study and work. It is central to how we reduce our impact on the environment when generating heat or electrical energy or power and to reducing our CO2 emissions which are widely claimed to have an impact on climate change. The generation of energy has traditionally been done through the use of fossil fuels; oil, gas, and coal, with some renewable energy produced from hydro power. Nuclear power was seen, and is still seen by some, as a method of generating energy with zero carbon emissions, but the disposal of the radioactive spent fuel is of major concern and this can counteract the advantages it has with zero carbon emissions. The development of most renewable energy systems is a recent innovation where energy is generated from renewable energy sources, eg. wind, solar, geothermal, bio-fuels, tidal, and wave. These systems have the advantage of generating power with virtually zero carbon emissions. The bio-fuels and geothermal systems can release power on demand, but most of the others depend of sources of energy outwith the control of human beings, and consequently, do not have a constant power output. For example, solar is not effective at night or when it is particularly cold and cloudy; wind is not effective at low wind speeds or very high wind speeds, and while tides are regular, they occur only a few times per week and wind is required to generate waves in our oceans or seas.



The main themes of the course are: conventional energy production, renewable energy production, converting energy from one form to another, industrial or domestic energy generation facilities, practical work with solar panels and wind turbines (integrating team work into the assembly process), and investigating careers within the energy sector. Optional areas covered are the size of an individual’s carbon footprint, oil and gas extraction or conventional energy systems; their contribution to the total energy generated in the UK and their environmental effects. Candidates will study the overall status of energy in Scotland, and in the UK, in general. They will explore the conventional methods of production, including their efficiency levels, various energy conversion principles, and how energy can be conserved. They will also explore the more recent developments in energy production using renewable energy techniques and will develop practical skills in the areas of plumbing, electrical, and mechanical engineering. Careers within the energy sector have been integrated with employability skills which are developed through practical activities. The three optional Units offer different routes for candidates. They can opt for an individual investigation and evaluation of their own carbon footprint, investigate the size of the market segment taken up with conventional production techniques and their sustainability, and explore the use of the national grid as a means of transmitting electricity throughout the UK, or have an in-depth study into the formation and extraction of one type of fuel in its raw state which is particularly relevant to Scotland, ie. offshore oil and gas.



Unit Outcomes, PCs and Evidence Requirements National Unit Specification: statement of standards Unit: Energy: Conventional Technologies and the Grid (Intermediate 2) Acceptable performance in this Unit will be the satisfactory achievement of the standards set out in this part of the Unit Specification. All sections of the statement of standards are mandatory and cannot be altered without reference to the Scottish Qualifications Authority. Outcome 1 Investigate conventional energy systems in accordance with a given brief. Performance Criteria a) Gather relevant information from a variety of sources according to the given

brief. b) Gather information on the contribution of selected energy systems to the UK. c) Gather information on the environmental effects of selected energy systems. d) Organise information gathered to produce clear summaries on the energy

contribution and environmental effects of conventional energy systems. e) Check that all steps have been completed in accordance with the given brief,

including completing the work to the agreed timescale. Outcome 2 Investigate electricity transmission and distribution through the national grid system in accordance with a given brief. Performance Criteria a) Gather relevant information from a variety of sources according to the given

brief. b) Gather information on ways of transmitting electricity through the national grid. c) Gather information on ways of distributing electricity to the consumer. d) Gather information on the environmental issues raised when using a national

grid system. e) Organise information gathered to produce clear summaries on the

transmission and distribution of electricity, including environmental effects. f) Check that all steps have been completed in accordance with the given brief,

including completing the work to the agreed timescale.



Outcome 3 Present findings on own energy consumption according to a given brief. Performance Criteria a) Present clear summary information on the contribution of conventional energy

systems. b) Present clear summary information on the environmental effects of

conventional energy systems. c) Present clear summary information on the transmission and distribution of

electricity. d) Present clear summary information on the environmental issues of the national

grid Evidence Requirements for this Unit Evidence is required to demonstrate the candidates have achieved all Outcomes and Performance Criteria. Performance and product evidence is required for this Unit. The evidence should be gathered at appropriate points throughout the Unit, in open-book conditions, in response to a given brief. Performance and product evidence Candidates will carry out an individual investigation according to the instructions in a given brief which covers all Outcomes and Performance Criteria. Findings will be gathered in a folio which the assessor will discuss with the candidate to check that all steps have been carried out as specified. The assessor will then complete and retain a checklist for each candidate as evidence that all steps have been carried out as specified in the brief. Product evidence Each candidate will produce a presentation which meets the Performance Criteria in Outcome 3. The method of communication in the presentation may be chosen by the candidate - written/oral, diagrammatic, graphical, and electronic - are all acceptable. The candidate may also choose different forms of communication - poster, leaflet, short talk, PowerPoint presentation - are all acceptable provided the Performance Criteria are met. An assessor checklist identifying the critical aspects of the presentation regardless of form should be completed and retained for each candidate. The critical aspects are:



• summary information must be clear • summary information of the contribution of conventional energy systems to the

UK • summary information on the environmental effects of conventional energy

systems • summary information on the transmission of electricity • summary information on electricity distribution systems • summary information on the environmental effects of the national grid Summary information of the contribution of conventional energy systems must cover three of the following; coal power, oil power, gas power, hydro power or nuclear power. Summary information on the environmental effects for conventional energy systems should include, where appropriate; carbon emissions, sustainability of fuel, fuel pipe lines, waste products, radiation, wildlife, climate change, or health. Summary information on transmission lines should include; cables, pylons, underground cables, efficiencies, and high voltages. Summary information on distribution systems should include; supply transformer stations, step down voltages (133kV or 110kV), distribution to consumers (230V), and domestic uses. The National Assessment Bank (NAB) item for this Unit contains an appropriate brief which covers the investigation and presentation requirements of the Unit and an assessor observation checklist. Centres wishing to devise their own assessments must refer to the NAB to ensure a comparable standard. NB Centres must refer to the full Unit Specification for detailed

information related to this Unit.



Employability Skills Profile In addition to the specific vocational skills developed and assessed in this Course, employability skills are addressed as detailed in the table below. For the purposes of the table, the Units are referred to as A, B, C and D as indicated. Mandatory Units

Energy: Introduction = A Energy: Domestic Solar Hot Water Systems = B Energy: Domestic Wind Turbine Systems = C Energy: Employability and Careers = D

Optional Units Energy and the Individual = E Energy: Oil/Gas Extraction = F Energy: Conventional Production Technologies and the Grid = G

Employability skill/attitude Evidence

• maintaining good timekeeping and attendance A, B, C, D, E/F/G

• maintaining a tidy work place B, C

• seeking feedback and advice A, B, C, D, E/F/G

• following instructions B, C

• working co-operatively with others A, B, C

• selecting and using tools correctly and for the purpose they were designed

B, C

• using Personal Protective Equipment correctly and working safely

A, B, C

• following basic drawings correctly B, C

• checking quality of work A, B, C, D, E/F/G

• working to agreed deadlines A, B, C, D, E/F/G

• organising work effectively A, B, C, D, E/F/G

• working confidently A, B, C, D, E/F/G

• willingness to learn new skills or techniques B, C

• working independently A, B, C, D, E/F/G

• reflecting on own performance B, C

• learning from past experiences B, C

• awareness of a range of careers and job roles D

• developing investigation skills A, D, E/F/G

• developing presentation skills A, B, C, D, E/F/G

• developing creativity skills A, B, C, D, E/F/G



Careers Scotland Support for School/College Collaboration for Scotland’s Colleges in the Scottish Enterprise area Since August 2006 Careers Scotland (SE and HI areas) has been funded by the Scottish Government to support College/School Collaboration and encourage and promote vocational educational choices for pupils in schools. Careers Scotland (now part of Skills Development Scotland) has an important role to play in selection, recruitment and pre-entry career guidance, as well as ongoing support and pre-exit career guidance, to ensure the pupils’ experience of SfW is capitalised upon in any future career planning. Careers Scotland activity takes place locally and nationally under 4 objectives: • Providing careers advice, guidance and employability support to pupils and

their parents pre, during and post vocational education experience, focusing primarily but not exclusively on SfW pupils - demonstrating how these educational choices have implications for future career options, and support the achievement of future career goals and supporting effective transitions

• Providing targeted support to pupils at risk of becoming unemployed who would benefit from undertaking a vocational course

• Partnership working to ensure vocational study is given parity of esteem with other school and post school options, focusing on recruitment / selection and retention of pupils on vocational courses

• Capacity building through relevant shared CPD events and resource development to increase understanding of the process of uptake of vocational options and facilitate more effective support to pupils navigating these options

For further information on Careers Scotland (SE)’s involvement in school/college collaboration locally, please get in touch with your Careers Scotland Regional contact: South East (Edinburgh & Lothians; Forth Valley; Borders) Stephen Benwell 01786 452043 [email protected] North East (Tayside; Grampian; Fife) Val Ormiston 01592-631155 [email protected] South West (Dumfries & Galloway; Ayrshire; Lanarkshire) Jean Geddes 01698 742192 [email protected] West (Glasgow; Dunbartonshire; Renfrewshire) Sandra Cheyne 0141 242 8338 [email protected]



Tutor Support Section



Learning and Teaching with Under 16s Scotland’s Colleges have made significant progress in meeting the needs of young learners. Our knowledge of the learning process has increased significantly and provides a range of strategies and approaches which gives us a clear steer on how lecturers can add to their skill repertoire. Lecturers can, and do, provide a stable learning environment where young students develop a sense of self-respect, learn from appropriate role models and see an opportunity to progress. There are basic enabling skills for practical application which can further develop the learning process for this group of students. So what are the characteristics of effective learning and teaching which will help to engage young learners? Ten ways to improve the learning process for under 16s (This list is not exhaustive!) 1. Activate prior knowledge and learning – ascertain what the learner knows

already and teach accordingly. Young people do have life experience but it is more limited than adult learners and they may not always be aware of how it will assist them in their current learning.

Tips - Question and answer; Quick Quiz; Quick diagnostic assessment on computer; present key words from the course or unit and see how many they recognise or know something about.

2. Tune learners into the Big Picture – the tutor knows the curriculum inside out and why each lesson follows a sequence, however the young learner does not have this information and is re-assured by being given the Big Picture.

Tips – Mind map or concept map; use visuals, for example wall displays of diagrams, photographs, flow charts; explain the learning outcomes in language they will understand; We Are Learning Today (WALT) targets and What I’m Looking For (WILF) targets; give clear and visible success criteria for tasks.

3. Use Advance Organisers – these are lists of the key concept words that are

part of the course or unit.

Tip – Highlight on any text the concept words that you will be using; make a visible list and put it on display – concept words can be struck off or referred to as they occur (NB this helps with spelling and independent learning as they do not have to keep checking meaning); highlight essential learning and action points.

4. Vary the teaching approaches. The two main approaches are instructing and demonstrating, however try to provide opportunities to facilitate learning.

Tips – Ask students what they know now that they did not know before, or what they can do now they could not do before, at appropriate points in the lesson or teaching block; ensure there are problem solving activities that can be done individually or in groups; ask students to demonstrate what they have



learned; use a range of question and answer techniques that allow participation and dialogue, eg. provide hints and cues so that they can arrive at answers themselves.

5. Preview and review of learning. This helps to embed previous learning and listening skills and provides another opportunity to elicit learner understanding. Consolidates and reinforces learning.

Tips – At the beginning of each lesson, or session, review previous learning and preview what is coming up; at the end of each lesson or session, review what has taken place and what will be focussed on next time – these can both be done through question and answer, quizzes and mind mapping activities.

6. Language in the learning environment. Do not assume that the language which is used in the learning environment is always understood by young learners, some words may be familiar but do not have the same meaning when used vocationally.

Tips - At appropriate points ask students what words mean; explore the various meanings of words to find out if they may have come across this language in another context; by looking at the structure and meaning of words there is an opportunity for dialogue about learning and to build vocabulary.

7. Giving instructions in the learning environment. This is one of the most difficult tasks a tutor has to do whatever the curriculum area. With young learners this may have to be repeated several times.

Tips – Ask a student to repeat back what you have asked them to do before beginning a task; ask them to explain the task to one of their peers; use the KISS principle – Keep It Short and Simple so that they can absorb and process the information.

8. Effective feedback. Feedback is very important for the learner to assess their progress and to see how and what they can improve. Provide opportunities to engage in dialogue about the learning function of assessment – provide details of the learner’s strengths and development needs either in written or spoken form. With younger learners identifying one or two areas for development is sufficient along with acknowledgement of what has been done well.

Essentially, learners are helped by being given a specific explanation of how work can be improved. You can also use summative assessment formatively, ie. as an opportunity to identify strengths, development needs and how to improve.

Tips – Ask students themselves to identify their own strengths and development needs – self evaluation; peer evaluation of work can be successful once they have been taught how to do it; the tutor can produce a piece of work and ask students to assess it anonymously; have a discussion about the success criteria for the task and ensure the students are clear about



them; allow learners to set criteria for success and then measure their achievements against these.

9. Managing the learning behaviour. Under 16s are coming into Scotland’s Colleges and training establishments from largely structured and routine-driven environments in schools and early feedback from those undertaking Skills for Work courses indicates that they very much enjoy the different learning environment that colleges and other training providers offer. Remember though that these are still young learners. They will still expect tutors to provide structure and routine, and will perform best in a calm, orderly learning environment. Young students will respond to firm, fair, and consistent management. Such routines have to be established quickly and constantly reinforced.

Tips - Health and safety is non-negotiable and consequences of non-compliance with the regulations should be made clear and adhered to at all times; set out your expectations from day one and provide a consistent message; have clear beginnings, middles and endings for each session; be a positive role model for your students, ie. be there before they are and manage the learners with respect; always deliver what you promise; build up good relationships and get to know the learners, make the curriculum interesting and stress the relevance of the learning; set up a positive behaviour management system. By following these guidelines you will build up two-way respect, which, while sometimes challenging to achieve, can be very powerful and work to everyone’s benefit.

10. Care and welfare issues. School/college partnerships mean increasing numbers of young learners in college. Tutors have to be aware of their professional responsibilities and mindful of young people’s rights. However tutors have rights too, in terms of feeling safe and secure in working with young people and there are basic steps staff can take to minimise risks. It is essential that colleges ensure that tutors have a working knowledge of the Child Protection policies (local authority and college documentation) and follow procedures and policies diligently. School/College Liaison Officers will be familiar with these documents and can provide support and advice. There are also training sessions on Child Protection available from SFEU (see the following page).

Tips - Avoid one-to-one situations with young students in a closed area; do not do or say anything that could be misinterpreted; if the opportunity arises, do some observation in schools to see and discuss how teachers use the guidelines for their own protection as well as the young person’s.

Most young people are a delight to work with and they will positively enjoy the experience of learning in college. However, there will inevitably be some who are disengaged, disaffected and who have not yet had an opportunity to experience success. ‘Skills for Work’ is a unique educational initiative that young people can be motivated to buy into – you as the tutor are key to the success of these programmes.



Skills for Work Workshops To take this 10 point plan forward and to add to it, you can attend one of SFEU’s ‘Get Skilled Up’ half day workshops for tutors delivering Skills for Work Courses, when we explore further the learning process and look at a range of specific teaching and learning techniques to use with the under 16 age group. To find out when the next event is visit our website www.sfeu.ac.uk or contact the Learning Process team at SFEU on 01786 892000. Child Protection Workshops These are run on a regular basis by staff at SFEU in Stirling and also in colleges. For more information on these workshops please contact members of the Access and Inclusion team at www.sfeu.ac.uk or contact the team at SFEU on 01786 892000.



General Guidance on Unit Delivery This unit is designed to introduce students to the size and relevance of the conventional energy power generation sector in the UK and how the national grid is used to transmit this electrical power to the domestic market. Issues that emerge from these generation and transmission technologies are also considered. It is an investigation based unit, where the student is given a set of specific power generation industry topics to investigate, and then present their findings. Note: you should take a precautionary approach when dealing with the terms grid and national grid as they can mean the same. In some documentation and data sources the distinction between where the grid starts and ends may be confusing to some students. Unit Induction An induction session in week 1 will prepare students well for the unit and help to clarify aims and expectations, what the unit is all about and any uncertainties they may have about the unit and how it will be delivered. It’s particularly important that they understand that the main learning approach will be student-centred, and what this means in terms of the investigation, organisation and presentation skills they will need to use. Induction may include the following: • an outline of the Unit content – what they’re going to be doing

• how it fits in to the Energy (Intermediate 2 level) course

• your plans for teaching the Unit – how they’ll be learning the skills: in this case, student centred investigation with tutor guidance and support.

• assessment methods and schedule

• where employability fits in – start by asking them what they think!

• the importance of regular attendance and good timekeeping to encourage the students to get into good habits – as if they were at work and in employment!

• you might also think about a site visit or invite a representative from a service provider to set the scene, and talk about the types of employment available in their organisation, and to reinforce the value that employers put on employability skills.

Learning and Teaching Approach The focus of this unit is on investigation skills that the candidate will use to access and organise relevant information and finally present their findings in a clear format. These notes are therefore not a comprehensive study of power stations and the grid because it is expected that the students will research and investigate the topics themselves. Some questions are posed at the end of each section to stimulate their investigations. The NAB for this Unit includes a set of worksheets to help the students focus on the Outcome requirements, organise their



investigation and structure their presentation. The NAB also contains a set of checklists for the tutor to keep track of student progress. Because of the investigative nature of the unit, the learning and teaching approach will be student centred. After some initial input from the tutor to set the scene, the students should work independently to source, organise and present the information required in the investigation brief. There should also be opportunities to carry out some activities as a group, to encourage collaborative learning. Presenting their findings to the class can help to develop confidence and improve knowledge and skills by sharing good practice. Tutor support and guidance will be ongoing as required. The Outcomes have been made as practical as possible to involve the students in developing their investigative skills. However they will need to be given guidelines on how to approach the work in terms of organizing their time to ensure that all stages of the investigation are covered. It would be helpful to work with the group to negotiate target dates for each stage of the investigation and to monitor progress throughout. Guidance on carrying out investigations and presenting findings are included in the Energy (Intermediate 2) Course Guidance Pack. This student centred approach will add value to the students’ learning experience by helping develop the following key employability skills as well as enhancing their knowledge of the oil/gas industry

• maintaining good timekeeping and attendance • seeking feedback and advice • checking quality of work • working to agreed deadlines • organising work effectively • working confidently • working independently • developing investigation skills • developing presentation skills • developing creativity skills

Although this unit could be entirely presented in a classroom environment it will be helpful if visits are arranged to power stations, if time permits. Alternatively you could use suitable video material or YouTube. Alternatively, you could invite professionals that have progressed through an apprenticeship scheme and then moved to the energy sector to come into the school/college. The information in the Student Support Section is not presented sequentially outcome by outcome. The students need to know about the concept of energy measurement and losses and the difference between renewable and non-renewable energy, before continuing their investigative study of power stations and the grid. The investigation approach is intended to stimulate the students’ thinking so that any future research that they undertake will benefit the environment.



On the following pages a range of online resources are identified that will help students particularly in the investigation element in Outcomes 1 and 2 and 3 and it would be appropriate to allocate class time in a flexible learning environment eg. a dedicated IT room. The online research activities will provide students with a more blended approach to teaching and learning. School students will be familiar with this approach. For students returning to study, you may need to spend time supporting them in the use of electronic resources. There is a wealth of information giving the percentage of electricity used by different generation sources, but there are conflicting figures around. One case to note is that hydro power is not always included in the renewable figure. Consequently, large errors could appear in students work when they are asked to locate percentage figures. To avoid confusion, restrict them to certain known sites. Be aware that a conflict of data sources may lead to confusion over which energy supply is the largest or smallest There are a number of ‘energy’ calculators available on the internet and you should choose the one you think your students will find most user friendly.



Resources Websites It is essential that computers are available for delivery of this unit as students will require Internet access to carry out their investigations. You should make sure that students know how to use different search engines and the ways to search using key words There is a wealth of information available via the web and the websites given in here are only a flavour of the material available. It is at the discretion of the tutor which web resources they choose to use. There are ‘YouTube’ links that are very helpful for showing the practical aspects of power lines, for example: http://uk.youtube.com/watch?v=Z3q9WdjD5wc&feature=related http://uk.youtube.com/watch?v=uEKbMMHAwm0 However, each centre will have its own guidelines for restrictive material. If students are allowed to access this site its use must be monitored carefully as there are video clips that may be unsuitable. For example some clips in the area of high voltage may be inappropriate, as they may demonstrate electrocution. Alternatively, tutors may choose show the clip of their choice to the students and deny access to students. Hydro Electric Power Hydro Electric Power and Dams: How hydropower plants work http://people.howstuffworks.com/hydropower-plant1.htm Hydro Electric Power and Dams: How hydropower plants work http://people.howstuffworks.com/hydropower-plant2.htm Glendoe Hydro Scheme (Scottish and Southern Energy) http://www.glendoe.co.uk/ Glendoe Hydro Power Station http://www.scotland.gov.uk/News/Releases/2005/07/28102617 Hydro Might Be the Renewable Answer: Times online Lewis wind farm http://www.timesonline.co.uk/tol/news/uk/scotland/article3821800.ece Micro-Hydro Power: RD Energy Solutions http://www.rdenergysolutions.com/technologies/hydro.html



Power Lines Maintenance of Overhead Power Lines: YouTube: Like a Bird on a Wire http://uk.youtube.com/watch?v=Z3q9WdjD5wc&feature=related Maintenance of Overhead Power Lines: YouTube: Agrotors Helicopter Power Line Maintenance http://uk.youtube.com/watch?v=uEKbMMHAwm0 Construction of Overhead Power Cables http://aluminium.matter.org.uk/content/html/eng/default.asp?catid=164&pageid=2144416510 Construction of HV underground power cables http://cse-distributors.co.uk/cable/tsle-single-core.htm Power Stations Careers, Power Stations and the Grid http://www.nationalgrid.com/uk/interconnectors/ List of Power Stations (International) http://www.power-technology.com/projects/#Nuclear Overview of Inverkip Oil Fired Power Station http://www.geo.ed.ac.uk/scotgaz/features/featurefirst3913.html Kaplan Turbines: Voith-Siemens Kaplan / Pelton / Francis Turbines http://www.vs-hydro.com/vs_e_prfmc_pwrful_prdcts_turbines_kaplan.htm Nuclear Power Stations Nuclear Power Stations: United Kingdom Atomic Energy Authority http://www.ukaea.org.uk/ Nuclear Power Stations: British Energy: Understanding Nuclear http://www.british-energy.co.uk/pagetemplate.php?pid=312 Dounreay Site Restoration Ltd: Links http://www.dounreay.com/links Dounreay Decommissioning: Photo Library http://www.dounreay.com/news-room/photo-library Sellafield http://www.nda.gov.uk/sites/sellafield/



Sellafield Image Library http://www.ialibrarydb.co.uk/index.php National Grid Supply Map of Suppliers - UK Electricity Companies http://www.nationalgrid.com/uk/Electricity/AboutElectricity/DistributionCompanies/ National Grid: About the Electricity Industry: Maintenance Trolley http://www.nationalgrid.com/uk/Electricity/AboutElectricity/ Energy: Domestic Issues Energy Consumption: Household Electricity Bills http://www.esru.strath.ac.uk/EandE/Web_sites/01-02/RE_info/hec.htm Energy Calculations and Data: Renewable Electricity in the Urban Environment http://www.esru.strath.ac.uk/EandE/Web_sites/01-02/RE_info/urban_design.htm Calculate Your Energy Bills: Energy Watch http://www.energywatch.org.uk/help_and_advice/saving_money/index.asp Electricity Power Distribution Handbook http://books.google.com/books?hl=en&lr=&id=CTmcEVsLy_cC&oi=fnd&pg=PA1&dq=Electricity+Supply+Handbook+1995&ots=qs86Wzgr94&sig=iRFFiTIJrHKqHd67WbQwTOgzCi0#PPP27,M1 Smart Metering: Smarter Metering Solutions from National Grid Metering http://www.nationalgrid.com/uk/Metering/smart_metering/ Energy: Environmental Issues UK Energy Calculator: BBC News Electricity Calculator http://news.bbc.co.uk/1/shared/spl/hi/uk/06/electricity_calc/html/1.stm UK Energy Calculator, Emissions and Generation Options http://news.bbc.co.uk/1/hi/sci/tech/4721284.stm Energy Resources: Fossil Fuels http://home.clara.net/darvill/altenerg/fossil.htm Impact on Economy, Social and Environmental: SEPA Application of the guidance to proposals for hydropower schemes http://www.sepa.org.uk/pdf/wfd/stake/reg/11may07/hydropower.pdf



Highlands and Islands Enterprise: Renewable Energy Electricity Generation in Scotland by Power Station Type http://www.hi-energy.org.uk/howelectricityisgenerated.html Publications Wood, E, (2005), ‘Hydro Boys - Pioneers of renewable energy’, Luath Press Limited. Ross D, (1995), Power from the Waves, Oxford University Press National Geographic (October 2007), Growing Fuel – The Wrong Way, The Right Way An investigation into the effects on people and equipment from sources of electromagnetic radiation, which are emitted from powered electronic and electrical equipment - a dissertation for the MSc in Safety Management with Environmental Management, University of Paisley, by James King May 2006 Shell UK (1985) Onshore Electrical Systems, Shell UK Ltd. The Open University (1982) Living with Technology - Energy, Open University Press Video/DVD Video – Lines of Power Module I – ELL 514 Navigator Productions Video – Lines of Power Module II – ELL 515 Navigator Productions



Signposting of Employability Skills In addition to the specific vocational skills developed in this Unit, students will have opportunities to develop and apply their knowledge and understanding of the employability skills.

1 Maintaining good timekeeping and attendance*

8 Following basic drawings correctly 15 Reflecting on own

performance

2 Maintaining a tidy workplace 9 Checking quality of

work* 16 Learning from past experiences

3 Seeking feedback and advice* 10 Working to agreed

deadlines* 17

Awareness of a range of careers and job roles

4 Following instructions 11 Organising work

effectively* 18 Developing investigation skills*

5 Work cooperatively with others 12 Working

confidently* 19 Developing presentation skills*

6

Selecting and using tools correctly and for the purpose they were designed

13 Willingness to learn new skills or techniques

20 Developing creativity skills*

7

Using Personal Protective Equipment correctly and working safely

14 Working independently*

The employability skills marked with an asterisk* are directly assessed in this Unit. However opportunities to learn and develop all of these skills are distributed throughout the course. Some of the skills can be delivered and assessed discretely but there are also many opportunities for this to take place during group activities. It is strongly advised that course teams meet together to discuss and agree a co-ordinated approach to the teaching and developing of the conventional energy technology throughout the Course and to ensure that the team has a common interpretation of the skills and attitudes. You should be on the lookout for evidence of competence in any of the conventional technology energy skills which may occur. There are many opportunities for this and plenty of overlap for any student who may have missed a specific lesson. Evidence observed out-with a formal lesson is perfectly valid. Further advice and approaches to integrating employability skills can be found in the Energy Course Guidance support materials.



Generating Evidence and Assessment Opportunities for Employability Skills

Employability Skills

Delivery Advice

Possible Activities/Contexts

Maintaining good timekeeping and attendance

• Discuss the importance of good timekeeping within the energy sector and

get students to assess their past timekeeping record. They should identify what improvements, if any, are needed. This should take place at the start of the Course and will set the expected standards.

• Staff should make their expectations clear right from the start of the course or Unit.

• A good initial activity is to have the students write the class guidelines themselves by identifying pros and cons of good and poor attendance and timekeeping – the benefits in the workplace of one and the consequences of the other.

• These guidelines or ground rules can be posted in the workshops and classes and referred to on a regular basis.

• Relate the ground rules to the world of work, eg. arrive on time, back from breaks on time etc. The measure of a student’s success in this aspect is for them to be honest in their appraisal of their performance and in making progress. ‘Distance travelled’ should be adopted, rather than a particular minimum percentage of classes attended.

• Attendance and timekeeping should be monitored throughout the Course. Students should be given feedback on their performance – both good and bad – in this regard. If you take note of patterns of performance it should be easy to give the students accurate feedback.

• Turning up for classes on time

• Returning from breaks on time

• Arriving on time to visits

• Sticking to planned work schedules regarding timing of activities

• Staying in class for the duration of the planned activity (no extended toilet breaks)

1



Seeking feedback and advice

• Seeking feedback and advice should be encouraged in this unit. However, this doesn’t mean that you are on call to answer all the students’ questions! The tutor’s role is more likely to be one of reassurance that they are on the right lines, guidance on different approaches they might take to find answers themselves and discussion to stimulate their own thinking.

• Young students can be wary of seeking advice for fear of highlighting their own lack of understanding or of being singled out for ridicule perhaps based on past experience. Discuss the benefits of getting feedback from staff and asking for advice. This can increase the students’ level of confidence in what they are doing and can reinforce their views of the direction they are taking. Success can be greatly increased by using knowledge and experience gained from others.

• Ask questions • Check work progress with

staff • Seek tutor feedback • Confirm instructions when

unsure

Checking quality of work

• Discuss how the checking of their tasks can lead to a higher quality of work and hence meet the standards required.

• Students should be made aware of acceptable standards in terms of the quality of their investigations and presentation of their work.

• Quality checking as work progresses

• Quality checking and review of final investigation findings and presentation

Working to agreed deadlines

• In the context of this unit, students could, as a group, negotiate and agree deadlines for each stage of the investigation.

• Discuss the need to keep to deadlines and the effects that can result if they are not maintained. Demonstrate the importance in the real world of keeping to deadlines eg. industry employs project managers whose main role is to keep work on schedule.

• Discuss progress with students in the context of the deadlines.

• Plan work schedule to meet deadlines

• Check progress against schedule and deadlines

3

9

10



Organising work effectively

• The student centred approach taken in this Unit is intended to help the students develop their organisational and planning skills, although guidance and discussion will be needed to achieve this

• Discuss how organising and planning work leads to a greater chance of meeting deadlines and meeting quality standards. Staff should emphasis a logical approach to organising work where any process is a combination of smaller steps taken one at a time.

• Planning their investigations

• Creating work schedules

• Planning out how to give a presentation as a group

• Planning out how to give an individual presentation

Working confidently

• Discuss the benefits that working confidently can give eg. being able to ask questions or give their point of view without the fear of feeling stupid, being able to stand up in front of others and give a presentation, to work without constantly needing reassurance.

• Students will have the opportunity to working confidently as they investigate tasks

• Students will have the opportunity to working confidently as they plan and present their work

• Staff should praise students for effort and good work at every opportunity to help keep their confidence high.

• Individual presentations

• Drawing up work schedules

• Investigations

• Discussions with staff and peers

11

12



Working independently

• Working independently is a key feature of this unit. Some students will embrace it while for others it will be more of a challenge. For the latter group, reassure that working independently does not mean that they will not be able to discuss their work with others or ask for guidance if they need it.

• Discuss the advantages and disadvantages of working individually, eg. advantages could include taking full responsibility, having complete ownership and not depending on others; to disadvantages such as, in extreme cases, not being able to share problems with others and having little social interaction.

• Students can be supported in this objective when you discuss their performance with them. Discussions can help to clarify sticking points and give them the confidence to work out the next steps for themselves.

• Retain brief notes on these conversations about progress as evidence for employability.

• Using information sources

• Planning and carrying out investigation

• Checking own progress

• Checking quality of work

• Discussions with tutor

• Self evaluation


Developing investigation skills

• Discuss the role of investigating to find out information. Students are very used to using the internet to find things out, but they don’t always see this as carrying out investigations.

• Discuss the various methods of finding out information -a wide range should be encouraged eg. Internet, interviews, papers, TV, books, experiments etc.

• In the initial stages, students should be given ‘directions’ to help find relevant information.

• Use a full range of resources for investigations. • Encourage students to interview people as well as consult books,

websites etc. • Emphasise the need to validate Internet sites – i.e. is it a reliable website?

• Investigations

• Interviews with family, friends etc

• Books, journals, Internet, papers, leaflets

• Extracting useful information

14



• Cross match information from two or more sources. • Log details of student investigations.

Developing presentation skills

• Students often find giving oral presentations a daunting task. Staff should demonstrate how presentations should be planned and practised. Students may feel comfortable using mobile phone technology to video a presentation, load it onto a computer and run it on the screen.

• Give encouragement to help them overcome fears. • Use a range of media to help overcome fears eg. PowerPoint or video • Where investigations are presented in written, diagrammatical and

graphical formats, time should be taken to discuss effective methods, layout, use of visuals etc, perhaps showing examples and having students evaluate them.

• Short talks

• Tutor support and discussion on presentation methods


• Folio preparation

• Planning

Developing creativity skills

• Creativity may have been introduced earlier in the Energy course as a skill which comes up with novel solutions to a problem. Creativity in design is the most usual way to demonstrate this but other ways can be used to show creativity eg. giving an oral / video presentation or presenting a report using diagrammatical, graphical and pictorial images.

• The student centred approach in this unit provides lots of scope for students to develop creative skills, particularly in the compilation and presentation of their investigation findings and they should be encouraged to be imaginative in how they present their findings.

• Encourage the integration of presentation methods.

• Individual presentation of work

• Planning work

• Use of technology



Suggested Answers to Student Activities Activity 1: Energy Consumption • Are both measuring the same? - ‘the average home’ and ‘a typical 3 bedroom

house’ • What is a typical 3 bed-room house? It depends on the number of people who

live in the house. • It depends what examples they used to come up with the average figures –

some houses have more electrical and electronic appliances than others. • The members of one household may be out all day at work and another

household may have retired people – so the amount of time spent in the house is also a factor.

Activity 2: Energy Consumption • The United States of America became the largest industrial nation in the world

in the 1920s – so they use a lot of energy • Americans had fridges/washing machines and televisions well before us in the

UK.

• America’s grid and generating capacity was more developed than ours so they could supply more consumers.

• America may have had much colder winters than us – so they had to heat their

homes more – many parts of the USA have severe winters. Activity 3 • In the 1920’s coal fires were the main form of heating but now we use

electricity. • We have many more electrical gadgets nowadays eg. Televisions and

microwaves, therefore we use far more electricity. • Not many homes had electricity in the 1920s as the national grid was not

established then. The supplies that were available were not standardised and the voltage and frequency was not supplied at fixed values across the country.

• We now have many more offices and industries that require electricity than in

the 1920s.



• The population or Scotland has remained steady for many years, but nowadays many more people are supplied with electricity.

• The metering of electricity is much more accurate today than was the case in

the past, so there may well be inaccuracies when comparing the figures. Answers Activity 4 Fossil fuels = 70.7% Nuclear = 22.3% Renewable sources 4.2% Imports = 2.8% Answers Activity 5 There is no absolute solution - each student may well come up with a different solution. This is an exercise in manipulating figures to suit. Answers Activity 8 - For the UK Answers will depend on the year chosen by the students. It would be interesting for them to select different years and then to compare. The Electricity Supply Handbook 1995 states that the energy sources used to generate electricity in Great Britain were in descending order of electrical energy share in 1993: Coal 53% - Fossil Fuel Nuclear 26% - Uranium Gas 10% - Fossil Fuel Oil 8% - Fossil Fuel Hydro 2% - Water Renewable 1% - Wind, Wave, bio-fuel, etc Note that renewable and hydro have been separated. Watch out for this when looking at any data. Hydro should always be included in the renewable figures. Answers Activity 9 - For Scotland The figures given below are for the percentage of electricity generated from power stations in Scotland for 1993. Nuclear power stations: 36% Coal fired Power stations: 33% Gas fired Power Stations 20% Renewable 11%



Note that oil-fired stations are not stated – this is because they are no longer used. Activity 10 • One way to address an energy shortage is to build more generating stations of

various types. There is not a simple unique solution. The energy supplies for the country require to be provided by energy from different types of power generation. The more environmentally friendly option is to generate electricity by renewable energy sources eg. hydro, wind and wave.

• The government does provide grants to certain sections of the community but

they have left out a large part of the population. They could provide more grants for all people to install insulation, double glazing, energy saving light bulbs and micro-generation.

• Once the plant is constructed, renewable energy is very cheap as it does not

require fuel to be purchased, although it does have continuous maintenance costs and damage to the equipment can take place due to adverse weather.

• The government could provide grants to renewable energy suppliers to make it

easier for them to connect to the grid. Activity 11 Glendoe near Loch Ness - Glendoe will be Scotland’s second largest conventional hydro-electric station and is the first large-scale station to be built since 1957. Tummel-Garry Scheme – this includes Pitlochry and Errochty Affric-Beauly Scheme Loch Shin Scheme Activity 12 Glendoe has an installed capacity of around 100MW (megawatts). The Errochty station in Perthshire had a capacity of 75MW when it was opened in 1957. You can see the massive difference in generating power, mostly due to technological advances in turbine and generator design and efficiency.



Activity 13 Initially the pioneers of hydro electricity were involved in a massive building project and many hydro stations were built up until the 1970s. Government policies then brought the hydro plant building programme to a halt. The figure for the UK for the last few years has been around 25%. Activity 14 Boxes 1, 2, and 3 represent the national grid. Activity 16 The substation is not secure – there is a large gap in the railings. Activity 17 As per the advantages and disadvantages listed at the end of each power station type.



Student Support Section



Tutor Note on Student Activities It is essential that computers with Internet access are available for teaching this unit as well as a data projector and electronic white board. This section includes both student notes and activities. These materials not mandatory but are offered to centres as a flexible set of materials and activities which can be selected, altered and used in whatever way suits individual centres and their particular situation. For example, in the case of the student activities you might want to talk through the instructions with the learners and then give the instructions out on paper as reminders. You are encouraged to adapt and use the materials creatively in ways which will best engage your students. It is not intended that the Student Support Section is issued to students as complete pack. The online research and activities will provide students with a more blended approach to teaching and learning. School students will be familiar with this approach. For students returning to study, you may need to spend time supporting them in the use of electronic resources.



Welcome to Energy: Conventional Technology and the Grid Introduction Throughout this unit you will investigate the location and types of power stations, including how they operate and how they are connected together to give us electricity in our homes.

Image Courtesy of RS Components Conventional technologies are the methods that we have used to generate electricity since the Industrial Revolution. The types of power station discussed in this unit are split into three different categories: • thermal • hydro • nuclear. Nuclear power stations can also be classified as ‘thermal’, but they will be discussed in another section of these notes, as with hydro power. The thermal power stations that generate electricity require a source of fuel and the traditional fuels that we have used are coal, oil, and gas. Oil-fired stations are no longer viable to run any more due to fuel costs. Oil, coal, and gas are known as ‘fossil fuels’ as they have been formed from the decomposition of organic animal and plant remains and they take many thousands of years to form. These fuel sources help identify the type of power station: coal-fired, oil-burning, gas-fired. We have a variety of these power stations throughout Scotland.



The grid is a network of overhead and underground cabling systems that are used to distribute the electricity to industry and households. The grid’s network of cables can be seen all over Scotland as they are mounted on large steel metal structures called pylons. Substations and transformers are also components of the grid system and will be discussed later.

Image courtesy of Scottish Southern Electricity



Renewable and Non-Renewable Energy: Carbon Footprint Non-renewable energy – One of the major causes of climate change. Power stations can use a fossil fuel source (ie non renewable source) of energy to generate electricity. The traditional fuels that we have used, and are still using today, are coal, oil, gas. These sources of fuel are classed as non-renewable. They are naturally occurring, and once they run out it will take many thousands of years for them to be replenished. These power stations have a ‘high carbon footprint’. Nuclear power stations which use uranium as a fuel however have a ‘low carbon footprint’. Renewable energy – Will help to slow down climate change. The power that is generated from wind, wave, tidal and hydro power stations are classed as renewable energy, but there are others. No fuel source is required but they need something to turn the turbine eg. wind or water. These are naturally recurring resources and Scotland has the potential to become a world leader in this area of power generation. These power stations have a ‘low carbon footprint’. Carbon Footprint The phrase ‘carbon footprint’ comes from one of our greenhouse gases, carbon dioxide. You’ll also hear these referred to as carbon emissions. Greenhouse gases are bad for the environment as they contribute to an increase in the earth’s temperature which causes the gradual melting of ice caps, due to rises in global temperatures. This is called ‘global warming’. These gases are created from the process of using fuel to generate electricity, although a large proportion also comes from transport. Although carbon dioxide is one of our largest sources of unwanted greenhouse gases, it also keeps our eco-system healthy. but it can have negative effects on our eco-system if the emissions continue to increase .There are proposals to introduce a method of re-cycling called ‘carbon capture’.



The United Kingdom carbon emissions are measured by the following units: MtC – Million tonnes of carbon. To convert this to millions of tonnes of carbon dioxide simply divide by 12 and multiply by 44.

© James King The non-renewable hierarchy for ‘Carbon Footprint’ The above diagram shows that coal has the highest carbon footprint and nuclear has the lowest. Hydro power is not shown in the above diagram as it is a ‘renewable’ source of energy.

Coal

Gas

Oil

Nuclear



Energy: Loss, Efficiency and Consumption The efficiency of a power station is directly related to the amount of energy (the fuel) you put in, compared to the amount of energy you get out, eg. some of the energy in the fuel is wasted. Energy is lost in the form of ‘heat’ from power stations and from homes in the form of hot air and gases, which will go up chimneys eg. if you burn coal in a fire, about 60% of the energy will go up the chimney – which is low energy efficiency. This means you are only getting about 40% of the heat. Power stations that burn fossil fuel have large cooling towers. This is because warm water is produced during the burning of fuel and carried away. This is waste – and makes the power station less efficient. The efficiency of this type of power station can range between 30-40%.

It has been argued that to use electricity as a form of heating is very wasteful because the power stations are so inefficient in terms of energy generation.

One solution to this is to modify the power station and use the waste hot water for the purpose of heating and the name given to this modified power station is a Combined Heat and Power System (CHP). This will take the efficiency back up to around 70%. In terms of domestic energy efficiency some solutions to improving the efficiency in your home are to insulate the loft, use low energy light bulbs, and install double-glazing.



Fossil Fuel, Grid and Home Energy Losses – energy lost means lower efficiency Fuel reserve or resource in the ground The mining process uses energy to extract – this is lost energy. Conversion process Energy lost in conversion eg. heat lost up chimney Transferring energy over the grid Energy lost during delivery eg. lost volts over long distances Consumers losing energy in homes eg. no insulation or double glazing Useful energy eg. actual energy used



The actual energy used is what the consumers use in their homes or businesses. The consumers of electricity must pay their supply company for what they use. We pay our electricity bills to the electricity suppliers based on a measurement of energy called ‘Kilowatt-hour’ (KWh). 1 watt is a rate of energy use of 1 joule per second Can also be written as W (watts) = J (Joule) / S (second). Therefore, 1 Kilowatt (1000 watts) = 1000 Joules/second. So: 1 Kilowatt hour = 60 seconds x 60 minutes x 1000 Joules Note: Mega = 1,000,000 1 KWh = 3.6 Mega-Joules (or 3, 600,000 Joules) We are charged an amount of money for every KWh of electricity we use in our homes. This amount of money charged per KWh is called a tariff. Our tariffs can be increased or decreased by the electricity suppliers eg. when there is an oil or coal crisis or shortage, then prices will increase eg. during the miners strike in 1974 or during the Gulf war. The tariffs will vary depending on the type of consumer. Industrial and domestic consumers are charged at different rates. Consumers can ask the electricity suppliers for specific tariffs. For example, a customer can ask for their electricity to be supplied on a ‘green tariff’. This green tariff means that the electricity supplied to you is from a renewable electricity source such as a wind farm.



Each consumer is provided with an electricity meter that measures the amount of electricity you use. We all have one in our homes.

© James King

A domestic electricity meter Example: If the hourly energy consumption for a person living in a small flat was 7.2 mega-joules, how many units of electricity would they consume in terms of standard electricity units (KWh)? Tip: Divide the consumed energy by 3.6 mega-joules as this is equivalent to 1 KWh. 7.2 mega-joules / 3.6 mega-joules = 2 KWh. Hence you would be charged for 2 units of electricity, so if the tariff was 10 pence per KWh then the person would be charged a total of 20 pence for one hour’s electricity use. Energy Consumption Activity 1 The two statements below are from different sources and are believed to be true, so why do you think the energy consumption figures are so different? • Today in the UK it is estimated that the approximate annual energy

consumption for a typical three-bedroom house is around 4300 KWh.



• Today in the UK it is estimated that the average home in the UK currently uses 3300 KWh of electricity each year.

Energy Consumption In the UK in the 1920s, the estimated average consumption of electricity for each person for one year was around 105KWh - 115KWh. For the same period in the USA the average consumption was around 850KWh - 950KWh. Activity 2 The USA consumption was higher than the UK, what does this suggest to you? Activity 3 In the UK we use a lot more electricity today than was used in the UK in the 1920s. Why has this increased significantly? Discuss this in groups and come up with three significant reasons why this is the case. Compare and discuss your group results with the other groups in the class.



The USA became the largest industrial nation in the world in the 1920s – so they used a lot of energy back then. America’s grid and generating capacity was more developed than ours so they could supply more consumers. Americans had fridges/washing machines and televisions well before us in the UK. Many parts of the USA have severe winters - much colder winters than us – so they had to heat their homes more. In the UK in the 1920s many people did not have electricity and used coal fires as their main form of heating and in many cases for cooking. It is very unhealthy to be in a smoky atmosphere for most of your life eg. it can cause severe breathing difficulties and cause permanent damage to your lungs.

© Ryan James King

A coal fire used for domestic heating Much of the electricity supply before 1926 came from private generating stations. Many of those supplied DC (direct current), which we do not require in our homes today. We now use AC, alternating current. Although the term alternating ‘current’ is used, in fact it is the generation of an alternating voltage that produces the required current. In today’s homes the main form of heating is by electricity, gas and oil. There are a huge number of electrical gadgets and domestic appliances on the market that we take for granted today but which weren’t available in the 1920s eg. televisions, washing machines, music systems, and many more.



Energy Consumption Y axis Units: Bn KWh X axis Units: Year The histogram shows Energy use in billion Kilowatt hours for the UK for 2006. (Note: Hydro Power is not included in the above figures) Activity 4 For the 2006 figures calculate the percentage that each category of energy contributed to the overall UK electricity demand. Activity 5 Use an energy calculator on the Internet to calculate the electricity requirements for 2020. The government target for the decade from 2020 - 2030 is to get supplies from renewable sources – this is anywhere between 40% - 60%. An energy calculator can be found at: http://news.bbc.co.uk/1/shared/spl/hi/uk/06/electricity_calc/html/1.stm

0

50

100

150

200

250

300

350

400

2006 2020

Fossil FuelsNuclearRenewablesImportsTotal Demand



Distribution of Electricity

© Ryan James King Pylons on Lewis

The photograph above shows the electricity supply running along the side of a road on the remote Isle of Lewis, Scotland. These pylons are smaller than the large metal pylon structures we see around mainland Scotland and the poles are made from timber. Telephone lines also use these timber pylons for telecommunications; known as telegraph poles, so don’t get confused with their use. The electricity poles are more obvious as they have large insulators. At one time electricity was not available on many of our remote islands and as we built more power stations and developed our grid we were able to supply more areas of our country.



Power Stations Oil Fired Power Stations Let’s examine three types of power station: • oil fired • gas fired • coal fired. These power stations are not always located close to the fuel source and many of them are often close to the sea or a water source, as the following example shows. The first oil-fired power station in Scotland was Inverkip power station, near Greenock which is located on the shores of the River Clyde.

Scotland’s first oil-fired power Station at Inverkip south of Greenock, built in the 1970s. Image courtesy of Scots Gazetter

The tall chimney, sometimes known as a stack or flue, is 700 feet tall (213m). The power station’s main source of fuel was oil but oil became very expensive, so this power station has not been used for some time now. The last time it was in operation was during the miner’s strike in the 1980s. The miner’s strike caused a shortage of coal so this reduced the production of electricity at ‘coal’ fired power stations.



The process for producing electricity from fuel oil is as follows: Create heat by: Burning oil Make steam by heating water A turbine is driven by steam The turbine drives a generator or alternator An alternator is connected to the turbine and this alternator rotates and generates what is known as AC - alternating current. Power is ‘stepped’ down through ‘transformers’ in ‘substations’ before distribution to consumers. Transformers can increase and decrease the voltage supply. Power distributed to consumers



Advantages of using oil for electricity generation: • More reliable than wind, solar or wave power • Oil is easier to get out of the ground than coal • Oil can be pumped through pipelines, so easier to transport • Oil fired power stations can take time to get to full power • Electricity can be generated constantly • It provides mass employment during it’s construction • It provides some employment for maintenance and running Disadvantages of using oil for electricity generation: • It is not renewable • Contributes to the depletion of oil reserves • The high cost of purchasing oil and price fluctuations • Oil has become more expensive, so oil-fired stations are not a feasible option

in today’s market • Oil has a high carbon footprint • Waste gases are given off • It takes up a very large area of land which is a scarce resource - causing

problems for wildlife eg. animals that used to live there. • Large pipelines are required and these have an impact on the land. If the oil is

not piped to the station, then easy access for large lorries will be required. • Large chimneys or flues are unsightly and give off noxious fumes and gases • During times of oil shortages, the generating capacity may be affected • Large pylons are needed to carry overhead power lines for distribution of the

electricity away from the power station and these are unsightly. • If people have houses near the power lines or pylons then they may be subject

to electromagnetic radiation emissions. Large voltages and currents give off large electromagnetic fields. At the moment there is no conclusive proof that this can cause cancer, but studies are ongoing.



Coal Fired Power Stations

Image courtesy of Scottish and Southern Energy The smoke you see leaving the cooling towers, as in the above photograph of Ferrybridge Power Station in South Yorkshire, is waste. It is a mixture of hot air and gases. In Scotland we have a number of coal fired power stations. For example, Longannet coal fired power station is located on the shores of the upper Firth of Forth near Kincardine Bridge in Fife. Fife at one time was a huge supplier of coal as it had many coal mines, however many of them are now closed. The coal has to be purchased from alternative sources such as Eastern Europe and it can be very expensive to import coal supplies. Around 6.2 billion tonnes of coal is consumed each year globally and the price of coal in today’s market (2008) is around £65 per tonne. Australia is one of the world’s largest producers of coal producing around 231million tonnes per year.



The process for producing electricity from coal is as follows: Coal is burned Steam is created to drive a turbine The turbine drives a generator or alternator The power generated is ‘stepped’ down through ‘transformers’ in ‘substations’ Electric power is distributed to consumers



Advantages of using coal to generate electricity: • If flue gas desulphurisation (FGD) is used then it can reduce emissions • Coal fired power stations can use low carbon coal • They do not make efficient use of energy and can take time to get to full power • More reliable than wind, solar or wave power • Electricity can be generated constantly • It provides mass employment during its construction • It provides some employment for maintenance and running Disadvantages of using coal to generate electricity: • Coal reserves are not renewable • Coal-fired power stations can take time to increase to full power. • Contributes to the depletion of the global coal supply - 40% of the world’s

electricity is generated from coal. • Coal is a fossil fuel and has a high carbon footprint. Burning coal produces

more carbon dioxide than burning oil or gas. Low carbon coal is still expensive to buy on world markets.

• The waste gases (COx, SOx & NOx) given off and released to the atmosphere through large chimneys or flues – are very unsightly and can be poisonous or hazardous.

• It takes up a very large area of land which is expensive and scarce as is the case for any large scale project. Flora and fauna will also be disturbed or lose their habitats, causing problems for animals that used to live there

• The site needs to be easily accessible for large lorries, which has an impact on local residents and roads. Coal can also be transported by rail.

• Large cooling towers and a lot of cooling water is required in the cooling process. The towers are very unsightly.

• During times of coal shortages, the generating capacity may be affected eg. miner’s strikes.

• Large pylons are required to carry overhead power lines (underground cables are even more expensive)

• The high cost of importing coal eg. The UK imports 51 million tonnes each year and in 2007 the UK used 62.8 million tonnes of coal.

• If people have houses near the power lines then they may be subject to electromagnetic radiation emissions. Large voltages and currents give off large electromagnetic fields. At the moment there is no conclusive proof that these can cause cancer, but studies are ongoing.



Gas Fired Power Stations

Image courtesy of Scottish Southern Energy Examples of gas-fired power stations in Scotland include the St Fergus natural gas plant in Aberdeenshire near Peterhead.



The process for producing electricity from gas is as follows: Gas is burned Steam is created to drive a turbine The turbine drives a generator or alternator Power is ‘stepped’ down through ‘transformers’ in ‘substations’ Power is then distributed to consumers for domestic use



Advantages of gas-fired power stations: • More reliable than wind, solar or wave power • Gas fired power stations are efficient • Gas fired power stations can increase to full power very quickly unlike some

other power stations • Transporting gas to the power stations is easier than transporting coal • Electricity can be generated constantly • It provides employment opportunities during its construction • It provides some ongoing employment for maintenance and running Disadvantages of gas-fired power stations: • Gas is not renewable • Gas has a high carbon footprint • Usage contributes to the depletion of natural gas supplies • Waste gases COx and NOx are given off and released to the atmosphere • It takes up a very large area of land which might have been used for housing,

industry, agriculture etc causing problems for the natural environment eg plant and animal habitats.

• Large pipelines to supply the gas has an impact on the land they are built across

• Large chimneys or flues are unsightly • During times of gas shortages, the generating capacity may be affected • Large pylons are required for overhead power lines • The high cost of obtaining (ie. drilling, extracting) gas • If people have houses near the power lines then they may be subject to

electromagnetic radiation emissions. Large voltages and currents give off large electromagnetic fields. At the moment there is no conclusive proof that the fields can cause cancer, but studies are ongoing.



Activity 6 Using the Internet, find locations in the United Kingdom where you may find the following types of power station: • Coal-fired • Oil burning • Gas-fired These three can come under a single heading of ‘thermal energy’. When you find a power station location mark it on a map of the United Kingdom using a colour coded system to identify the types eg. black for coal; yellow for gas and brown for oil.



Nuclear Power Stations Nuclear power stations rely on a fuel called uranium which is mined in other parts of the world. The process of generating nuclear power requires very little uranium, hence its appeal eg. a very large output of power for very little fuel used. Nuclear power currently produces around 11% of the world's energy needs, however this figure will vary over decades as government policies change and in the UK our nuclear generating capacity may well reduce as we move towards renewable energy sources. Nuclear energy is a special case in that it uses very little uranium compared to the massive amounts of coal required for coal fired stations. Therefore nuclear power has a relatively low impact on the environment and has been classed as having a ‘low carbon footprint’. Although nuclear power stations have a ‘low carbon footprint’ they fall into the category of ‘non-renewable’ because they use the natural resource uranium, which is mined from deep underground and will eventually run out. Nuclear power stations have a number of technical challenges associated with their design. They have to be specially designed as the nuclear reaction takes place in a nuclear reactor, which has to be reinforced and very thick to prevent the radioactivity escaping. Dounreay Nuclear Power Station near Thurso in Caithness in the North of Scotland was ‘dome’ shaped but the plant has been closed. Activity 7 By using the Internet, or alternative resources, find the locations of the nuclear power stations in the United Kingdom. When you find each location add these to your map, remembering to colour code them eg. marking them in ‘red’



The process for producing electricity from nuclear fuel is as follows: Create heat by a process of nuclear fission Make steam by heating water The turbine is driven by steam The turbine drives a generator or alternator Power is distributed to consumers



Dounreay

Until the 1950s, Dounreay was an area of grazing land on the remote Northern coast of Scotland, known only for the presence of a 16th century ruined castle, a farm and a World War 2 aerodrome that had never become operational.

In 1954, the UK government selected it as the location for the national centre for research and development of fast breeder reactors, a new type of atomic energy. Fast reactors were thought to have good potential for electricity generation as they made more efficient use of uranium fuel – effectively breeding more fuel than they consumed. This was important with the scarcity of uranium at the time.

Dounreay proved that fast reactors could work. It also demonstrated that plutonium could be recycled by reprocessing it efficiently and economically. But by the late 1980s uranium was no longer in short supply, and the UK government decided that fast reactors would not be needed for commercial electricity generation. Funding for the Dounreay research programme ceased and the last reactor shut down in 1994. The term used to describe the dismantling of the buildings is called ‘decommissioning’.

Decommissioning Dounreay Nuclear Power Station Image courtesy of United Kingdom Atomic Energy Authority (UKAEA)



Restoring the 140-acre Dounreay site on the North coast of Scotland is one of the most complex nuclear decommissioning tasks in the world. The site’s history in fast reactor and fuel cycle development presents significant decommissioning challenges. The clean-up will be completed by 2033 at a cost of £2.9 billion. Our understanding of the tasks involved has enabled us to cut the estimate by £1.3 billion and halve the programme timescale since the original Dounreay Site Restoration Plan was published in 2000. The tag of ‘low carbon footprint’ does not include decommissioning costs, which involves dismantling the buildings and reactors. UKAEA has successfully managed the transition from operations to decommissioning. Decommissioning progress has included dismantling of redundant facilities, construction of state-of-the-art waste treatment plants and infrastructure improvements to prepare for the decommissioning work ahead.



There are safety issues to consider with nuclear power generation. There is always the possibility of a major accident eg. Chernobyl in Russia. Secondly, the ‘waste’ that is produced from the nuclear power station is contaminated with ‘radioactivity’. This contaminated waste cannot be destroyed or treated. The nuclear re-processing plant at Sellafield in Cumbria, England deals with a major part of this waste. This radioactive waste is categorised into three levels: • low level radioactive waste. • intermediate level radioactive waste • high level radioactive waste. Reference: http://www.nda.gov.uk/sites/sellafield/



Nuclear industry experts have considered many options for the disposal and the storage of this radioactive waste. Two such ideas included burying the waste in the Polar icecaps and the other was to send it into space. Both of these options have not been taken up (not surprisingly!). The favoured method is to seal the waste within a concrete container and then bury the container in deep shafts underground. This will allow the radioactivity to fade away, but this can take many hundreds or thousands of years. The factor that determines how fast the radioactivity levels fade away is called the half-life. Like many industrial sites, power stations come to the end of their useful life and nuclear power plants also face a technical challenge in this respect. The decommissioning of Dounreay Nuclear Power Station in Caithness will take many years to complete and cost billions of pounds. This is because you cannot simply use a bulldozer to knock it down; it has to be taken apart bit by bit. As radioactivity was present in the reactor building it means that the structure has also been contaminated. So any dismantled part of the building will then have to be treated as radioactive waste. It has been suggested that workers in nuclear power stations are the healthiest workers in any industry. The reason for this claim is that nuclear workers have personal radioactive monitors which are worn at all times. Regular stringent medical tests are also a requirement so any change in workers’ health will be immediately detected and treated. Many years ago it was thought that nuclear energy was the answer to our energy needs. Sir Anthony Wedgewood Benn, Energy minister at the time (1975) implied that we may eventually get free energy. This has not turned out to be the case. Some nuclear power stations are being de-commissioned but plans are being put in place in England to build more modern nuclear power energy. In Scotland the government is currently not planning any more nuclear power stations.



Advantages of nuclear power stations: • Low carbon footprint – but this does not include the de-commissioning costs • Cheaper than some other forms of electricity generation • Much more reliable than wind, solar or wave power • Can increase to full power very quickly unlike some other power stations • Electricity can be generated constantly • Considerable employment is provided during its construction phase • Some employment is provided for ongoing maintenance and running Disadvantages of nuclear power stations: • Nuclear power and uranium is not renewable. • The power station can take years to build. • Finding a suitable site can be difficult as the impact on residents and the

environment may be unacceptable. • There is a risk of contaminated radioactive waste escaping from the site to the

sea and land. • Waste that is collected is radioactive, much of which cannot be treated. This

radiation is called ‘ionising radiation’ and will cause cancer if the dose is high enough.

• It takes billions of pounds to decommission a nuclear plant. • It can take anywhere up to 25 years to decommission a nuclear plant. • A reprocessing plant needs to be available to take the radioactive waste. • If a major plant fault occurs it may cause a large scale nuclear disaster with

serious health affects and thousands of deaths eg. Chernobyl in Russia. • Could be the target of terrorists. • If people have houses near the power lines then they may be subject to

electromagnetic radiation emissions. Large voltages and currents give off large electromagnetic fields. At the moment there is no conclusive proof that the electromagnetic field can cause cancer but studies are ongoing.



Activity 8 Find out the approximate percentage of the UK energy market that was supplied by each of the fuels (nuclear, gas, oil, coal). Record this on a ‘pie’ chart or ‘histogram’ or a ‘table’. Choose any year from 1950 – 2007 Suggested reference source: http://www.berr.gov.uk/energy/statistics/source/index.html http://www.berr.gov.uk/files/file46983.pdf page 24 ‘Energy supplied by fuel type1980 to 2007’ Activity 9 Determine the approximate percentage for Scotland that was supplied by each of these fuels. Record this on a ‘pie’ chart or ‘histogram’ or a ‘table’. Choose any year from 2000 – 2007. Suggested reference source: http://www.scotland.gov.uk/Topics/Statistics/Browse/Environment/seso/sesoSubSearch/Q/SID/98 Activity 10 Today, we are faced with massive price increases in domestic electricity and gas from energy providers. Investigate steps you could take to reduce energy consumption in your home and how the government can help improve electricity supplies.



Hydro Power Stations Hydro-electric power stations work on a mechanical principle using water flow to drive turbines which then turn a generator. There are just under 60 of these power stations located throughout Scotland. The first hydro power scheme in Britain was built in the 1880s at Cragside, Rothbury, Northumberland and used to provide power to the house of Lord Armstrong, a Tyneside shipping magnate. The first hydro power generation station in Scotland was built in 1890 by the Benedictine Monks at Fort Augustus and produced 18 KW at 130 volts. Hydro Power Station at Pitlochry, Perthshire The hydro station at Pitlochry has turned into a major visitor attraction where visitors can see salmon leaping up and down a ‘fish ladder’ or ‘fish pass’ which serves the purpose of allowing the fish to pass up and down the river for spawning. This has been an environmental success for salmon. Activity 11 Group exercise Find the locations of 4 hydro power stations in Scotland and add these to your map in blue. Write a brief summary of the background of each hydro power scheme and present this to the class. Activity 12 Find the maximum operating capacity of one of the hydro power stations, that is, the maximum output power it can generate.



Hydro Power Engineers There were many famous Scottish engineers and businessmen who were very important in the development of hydro power. They are known as the pioneers of hydro power: Tom Johnstone, born in Kirkintilloch in 1881 – mainly worked in politics and became an MP and was responsible for founding the North of Scotland Hydro-Electric Board (NoSHEB). James Williamson, CBE, (1881- 1953) born in Lanarkshire, Scotland, graduated from Glasgow University and worked as a civil engineer on many large projects, including hydro-power schemes. He identified 102 possible hydro schemes in Scotland. These were not all-large scale and just over 50% of them were built. Sir Edward MacColl (1881- 1951) completed an engineering apprenticeship in the shipyards on the banks of the river Clyde. He then joined the Glasgow Corporation Tramways Department and eventually became Chief Technical Engineer with the Clyde Valley Electric Power Company. He played a large part in Scotland’s first major hydro-electric scheme near the Falls of the Clyde creating a public power supply. Choosing a site Before a suitable site can be chosen there are many factors that have to be considered eg technical factors, environmental preservation issues and community amenities. Civil engineers need to make careful calculations to work out how much electrical energy can be generated. This depends on the flow/quantity of water, and the height from which it has fallen (the head). The higher the head, and the larger the flow, the more electricity can be generated. A simplified equation is: Power (potential) = Head x Flow x Gravity

• The power is measured in Watts • The head is measured in metres • The flow is measured in litres of water per second • The Acceleration due to gravity is measured in metres per second



Civil engineers and designers can build four types of hydro scheme. First they need to consider the topography and geology of an area. This means • the suitability of the landscape • the water flow • the water storage • the annual rainfall. Depending on these factors the type of hydro scheme is chosen: 1. Run of river scheme (eg. used at the falls of the river Clyde) The run of river scheme only requires minimal water storage, therefore no dam is required. The power output is determined by the amount of river flow. A barrage or weir is built across the river to increase the volume of water which can be passed through the turbines. 2. Dam scheme (eg. Strathfarrar scheme) Large volumes of water are stored behind a dam and this also provides a high head of water to drive the turbines. Damming a broad river may not be economically justifiable, but deep glaciated Highland valleys can be suitable. 3. High head scheme (another type of dam scheme) This utilises high catchment areas, usually flat plains that are high up in a valley. Using a network of tunnels and pipelines specially designed to withstand high water pressure, it delivers the water to the turbines by the shortest and steepest routes. 4. Pumped storage scheme (used at the Cruachan power scheme in Argyll) Pumped storage schemes do away with the need for a large dam, although a smaller dam is used. These schemes have two reservoirs and reversible turbines that are used to pump the water back up to the upper reservoir during times of low demand eg. at night. One problem with pumped storage power stations is that they are not self sufficient as they require an external source of power for the pumps.



Turbines Turbines are used in all power stations. A turbine is the part of the machinery that rotates as a result of water power, in the case of hydro, and there are a number of designs available.

A turbine at Pitlochry Hydro Power Station

A Kaplan Turbine Image courtesy of Voith-Siemens

An alternator is connected to the turbine and this alternator rotates and generates what is known as AC - alternating current.



A sinusoidal AC waveform

Image courtesy of RS Components Although the term alternating ‘current’ is used, in fact it is an alternating voltage from the generator which produces the required current.



The process of generating electricity from hydro power: Water from a loch or reservoir is directed through pipe work A turbine is driven by water flow The turbine drives a generator or alternator Power is ‘stepped’ down through ‘transformers’ in ‘substations’ Power is distributed to consumers Hydro power stations can cope better with ‘peak load’ demands than thermal power stations. Extra power can be turned on and off very easily. Peak load demand is when the consumers increase their demand at the same time eg. at meal times or when everybody switches their kettles on during a commercial break on the TV coverage of major events.



Activity 13 Why has the importance of hydro power risen so dramatically in the last 50 years or so? Hydro power: Scotland compared to the world Hydro power provides around 25% of the world’s electricity and China is now leading the way in building new hydro plants. As a comparison, coal-fired power stations provide 40% of the world’s electricity.

Graph courtesy of Voith-Siemens The above diagram shows some of the largest hydro plants throughout the world. The ‘blue’ symbols represent water turbines, which are one of the main parts of the hydro generating process. Although the building of power stations came to a halt around the 1970s, more recent governments have again given the go ahead. In 2003 the most recent hydro plant was built at Glendoe in Scotland. This was the first large scale hydro scheme to be built for around 40 years. Further details about the scheme are available on the project website: http://www.glendoe.co.uk/



As with all large building projects, construction of the scheme did affect the landscape. This happened mostly at the time of construction.

Large temporary buildings form a camp where the workers lived during

construction of the power station. Image courtesy of Scottish and Southern Energy

The camp itself is large, as shown in the above picture. You can see it does affect the landscape. These camps are normally temporary and can be removed easily and the land returned to near its original condition. With all the main components of the hydro scheme being underground, the dam and reservoir are the main structures that will be visible. However, they cannot be seen from any home or public road and around the reservoir is used only for sporting purposes and is not particularly popular with hillwalkers.

Dam area in July 2006 Loch Ness



Advantages of hydro power: • It uses a renewable source which occurs naturally ie. water from rainfall • No carbon emissions • Once the dam is built, the energy is far cheaper than any other renewable

source • Minimal waste or pollution produced • Much more reliable than wind, solar or wave power • Water can be stored above the dam to cope with peaks in demand • Hydro-electric power stations can increase to full power very quickly unlike

other power stations • Electricity can be generated constantly • It provides large scale employment during its construction • It provides some employment for maintenance and running • The local community can benefit from increased business • They are generally well hidden from the public. • A new habitat can be created by the building of new reservoirs • Dams can also be used for flood control or to irrigate land, so building costs

can be shared • Scotland has an ideal landscape to build more hydro stations • Can help promote tourism - Pitlochry power station has turned into a visitor

attraction as the designers of the scheme built in a ‘salmon leap’, where you can watch salmon. This is called a fish pass or fish ladder.

Disadvantages of hydro power: • Dams are very expensive to build • Building a large dam will flood a very large area upstream, causing problems

for animals that used to live there • Finding a suitable site can be difficult, the impact on residents and the

environment may be unacceptable and a large dam unsightly • Water quality and quantity (volume) can be affected downstream, which can

have an impact on plant life • Hydro has a small carbon footprint but there is energy used up during

construction eg. transport. • During times of drought, the generating capacity may be affected • During construction there is some damage to the landscape. • If people have houses near the power lines then they may be subject to

electromagnetic radiation emissions. Large voltages and currents give off large electromagnetic fields. At the moment there is no conclusive proof that the electromagnetic field can cause cancer but studies are ongoing.



The National Grid

Pylon supporting transmission power lines Image courtesy of Scottish and Southern Energy

The photo above shows a large metal structure called a ‘pylon’ which is one of the main parts of the gird network for carrying high voltage cables. Pylons do vary in size. In general we can say the higher the voltage then the larger the pylon. Therefore smaller pylons are used for lower grid voltages. Many people regard pylons as unsightly and don’t want them near their homes. This attitude is sometimes known as ‘Nimby’ (Not in my back yard).



Before 1926 electricity in the UK was produced by private generating stations and there was no standardisation as they were located to supply particular districts. This meant there were variations in the voltage, current and frequency. In 1926 Electricity (Supply) Act established the National Grid and provided standardisation across the country. This gave us the domestic standard we operate today eg. AC 240 volts, 50 Hertz. The national grid now means that all power stations are linked in a large network which feeds into the grid. The Central Electricity Generating Board (CEGB) was set up in 1947 and took over all electricity generation. This meant that it now owned and operated the grid, and controlled the operation of all power stations. In the UK today the national grid network consists of many operators and companies. They can be split into the following categories: • Generators - responsible for generating the energy we use in our homes and

businesses. Generated electricity flows into the national transmission network and through to the regional distribution networks.

• Distributors - are the owners and operators of the network of towers and

cables that bring electricity from the National Transmission Network to homes and businesses. Even so, they are not the organisations that sell electricity to the end consumer. This is carried out by organisations that make use of the distribution networks to pass the energy commodity to your property - the suppliers.

• Suppliers - are the companies who supply and sell electricity to the consumer.

The suppliers are the first point of contact when arranging an electricity supply to domestic, commercial and smaller industrial premises.

In 1990 Britain introduced a competitive supply market in terms of electricity. Since 1999, over 19 million customers have changed supplier, with some domestic consumers realising significant savings on their energy bills. As a result of competition, UK energy prices have fluctuated since1999, and there have been both increases and decreases in prices. One part of the grid is a network of overhead power cables attached to metal structures called pylons. There is also a network of cables that are buried underground. These distribute the electricity across the country at very high voltages because this reduces losses during transmission. There are also underwater cables buried in deep seabed trenches, which are connected from Dungeness on the southern tip of Kent in England to Les Mandarins on the French coast. This is called the cross-channel DC link. This means we can ‘sell’ electricity to France or we can ‘buy’ electricity from France.



When the national grid was established the transmission voltage was 132,000 volts (132KV). As the grid developed a new ‘super-grid’ was superimposed on to the existing grid. This new super-grid introduced much higher voltages of 275,000 V (275KV) and 400,000V (400KV) which now form the main trunk route to transfer ‘bulk’ power. The high voltage overhead cables are made from aluminium on the inner core with an outer layer of steel armoured wire covering them which takes the strain. The aluminium is the conductor, which is instead of copper. No outer insulation is required. The distance and height of the pylons that hold the overhead cables is carefully calculated to take the weight and strain of the heavy cables. During the winter layers of ice can form on the outer steel wire and this adds more strain. Therefore a wide variety of cable specifications are available to meet the demands for large alternating currents, and different climates and types of terrain will affect the layout and design of the power lines.

Image courtesy of RS Components Underground high voltage cables require a different specification, as they have to be resistant to water penetration and be able to insulate the conductor from physical damage. The conductor can be either aluminium or copper and the insulation is a plastic material called polyethylene. The layers in between consist of a wire armoured layer and a screen layer. This is to prevent mechanical damage and to reduce electrical interference. It is twice as expensive to install underground cables than overhead cables. Mechanical diggers have been known to dislodge and damage underground power cables and thereby cause power cuts.



Activity 14 The diagram below shows the steps involved in reducing the voltage from a very high voltage down to the voltage we use in our homes. What do boxes 1, 2, and 3 represent? 1 2 3

Generator in power station 25,000 V (25 KV)

Step-up transformer 25 KV / 400 KV or 25 / 275KV in power station – Transmission

Step-down transformer 400 KV / 132 KV or 275 KV / 132 KV - Transmission

Step-down transformer 132 KV / 33 KV

Step-down transformer 33 KV / 11KV

Step-down transformer 11 KV / 415 V

Local distribution to consumers 415 V / 240 V



Image courtesy of the National Grid The picture above shows a maintenance trolley that can travel along power lines. Such trolleys can carry a number of people to perform maintenance work. The large cooling towers of a thermal power station are shown in the background. Activity 15 Now watch maintenance being performed on high voltage power lines at: http://uk.youtube.com/watch?v=Z3q9WdjD5wc&feature=related

Image courtesy of Scottish Southern Energy



Simplified flow diagram of the generation, transmission and distribution of electricity: Alternators (also known as generators) change other forms of energy into electricity. Transformers change system voltages as required, either up or down. Transmission lines/system carry electricity for the grid. The grid moves electricity towards the consumers. It ensures that in principle any consumer can be supplied from any power station. Distribution systems distribute electricity from the grid to consumers.



Substations Substations are an integral part of the grid and it could not work without them. A substation provides the inter-connection point for transformers, busbars, switchgear, and protection. They are very dangerous and access is restricted to highly trained personnel only. Substations vary in size and operate at different voltages and can take up a large or small area of land depending on the size of the voltage present. Large substations for very high voltages would be located very near to a power station. Smaller substations operating at much lower voltages can be seen along the roadside especially in urban areas. There are thousands of small sub-stations throughout the United Kingdom. Transformers The major component of a substation is a transformer. It can step the voltage up or down eg. the voltage can be ‘increased’ or ‘decreased’. High voltage transformers can be very large and if you listen carefully you will hear a ‘hum’ coming from them. Hundreds of transformers are connected all along the grid to step the voltage down in a gradual fashion. They vary in size and shape with some being the shape of a barrel and others square.

A large transformer The image above shows a large transformer adjacent to a public pathway. The circular tubes round the transformer contain the coolant, usually oil. The part of the transformer where the yellow label is placed is where the underground cables are connected. Access is denied to the public as the high currents and voltages of the transformer are dangerous.



Transformer located in a small/medium voltage substation Activity 16 Can you spot the problem with this substation?



Busbars Busbars are made from lengths of copper bar and take the place of cables. Copper bar is very expensive so busbars are only used where short distances are needed eg. within the confines of a substation. They are not used to transmit electricity across the grid.

Image courtesy of RS Components

Busbars are solid and rigid and can be bolted to the transformer and switchgear so providing better connectivity. Cables can be blown about by strong winds and cause faults whereas busbars are not affected by the wind. If the busbars are very large they can carry far more current than a cable. They are easily machined and can be drilled and shaped to fit any connection requirement to switchgear and protection equipment. Disadvantages of busbars: • copper is expensive • copper oxidises when exposed to the air and changes colour • copper will deteriorate with extremes of weather



The larger the current and voltage is – the more dangerous it is!

Image courtesy of RS Components

Image courtesy of RS Components The above image shows a current transformer with a busbar passing through it. This is one method of measuring the current leaving a power station substation.



Switchgear Switchgear is an electrical switch that opens or closes a circuit and is also known as a circuit breaker. When high voltage circuit breakers open a circuit with a large current passing, it causes a large ‘arc’ to occur. These arcs look very similar to lightning strikes but they are contained in the circuit breaker by a protective shield called an ‘arc chute’.

Image courtesy of RS Components Switchgear also offers protection to circuits as they will open the circuit under fault conditions.

A circuit breaker

Image courtesy of RS Components A small circuit breaker is shown above. The larger the voltage and current the larger will be the circuit breaker.



A household consumer unit The image above shows a consumer unit, which is an item of ‘switchgear and protection’, used in homes to protect consumers. It shows a row of small circuit breakers for protection in the event of a fault. Protection Circuit breakers are preferable to fuses as they are more efficient and safer, although it is still very common to find fuses in many installations. When higher voltages and currents are used then the fuse size needs to be much larger. When a fuse blows you have to discard it, but when a circuit breaker trips you can reset the switch.

A range of fuse sizes and types Image courtesy of RS Components



A household fuse The image above shows a fuse as is used in household plugs. This fuse gives a form of protection; it breaks the circuit when the fuse blows. This fuse is suitable for 240 volt and a fault current of 3 amperes. Fuses are being gradually replaced by miniature circuit breakers and residual current devices as a means of electrical fault protection in homes.



Advantages of the National Grid • Having a grid allows easier connection from all

types of generating station both renewable and non-renewable.

• Electricity can be supplied constantly and there is very little interruption.

• Overall control is from a central point using computerised automation.

• It provides employment opportunities during its construction.

• It provides ongoing employment for maintenance and running.

• Remote communities can be connected to the grid.

• Britain can sell electricity to foreign customers eg. France.

Disadvantages of the National Grid • It is expensive to install the cable systems. To install underground cables is

nearly twice as expensive as overhead cables. • Carbon emissions occur from certain power stations. • Building large pylons can be very unsightly. • Finding a suitable route can be difficult as the impact on residents and the

environment may be unacceptable. • Pylons can cause a hazard to low flying aircraft. • Pylons can be a danger to the public if they trespass near the overhead lines. • During construction there is some damage to the landscape. • If people have houses near the power lines then they may be subject to

electromagnetic radiation emissions. Large voltages and currents give off large electromagnetic fields. At the moment there is no conclusive proof that these electromagnetic fields can cause cancer but studies are ongoing.

• Large transformers are cooled by oil and if there is a leak of oil then it may contaminate the surrounding land.

• Lightning can create large electrical surges and cause major damage and disruption to the service.

• The maximum power that the grid can produce for the UK is around 50 Giga-watts (50GW) or 50,000,000 Mega-watts.



The Future of Electricity Supplies The way forward is to use renewable electricity supply sources and have non-renewable sources for back up or in the case of emergency. More research, development and investment should be made to install and design renewable forms of electricity to replace fossil burning power stations. Renewable forms are: • wind • wave • tidal • hydro • solar Professor Stephen Salter of Edinburgh University and a wave energy device inventor summed up ‘wave energy’ very well: “Efficiency itself is no concern when the gods pay for the waves” (Ross, 1995). – In other words, there are virtually no fuel costs. Scotland is ideally suited because of its natural environmental resources to install all forms of renewable energy. Micro-renewable energy sources will become more popular eg. PV solar, hydro, wind. This means that you could have your very own wind turbine attached to your house or nearby to generate your own electricity. It’s also important to reduce demand for electricity in the future. This means simple things like: using energy saving light bulbs, better insulation in houses and buildings, double glazing, standby modes on electrical products and switching off when not in use. ‘Smart’ meters will help raise awareness and in turn reduce energy use. (eg. http://www.bettergeneration.co.uk/ideas-for-saving-energy/smart-electricity-meters.html http://www.energywatch.org.uk/uploads/Smart_meters.pdf )



Activity 17 Group Exercise: You are in the government planning department for energy and your group has to come up with the most suitable new power generating system for Scotland. Discuss the major advantages and disadvantages of each of the following types of power generation and then present your case to the class. • Coal-fired • Nuclear • Hydro • All other renewables



Glossary of Terms You can add to this list as you come across new terms. It should be filled in as part of your investigation. Some have been listed as a starting point.

Term Meaning Alternator An electric generator that produces alternating

voltage and current

Amperes The electric unit of current

Arc A luminous electrical discharge between two electrodes or other points

Busbar A copper bar that conducts electricity

COx Carbon content in gases

DC Direct current

FGD Flue Gas Desulphurisation

GW 1,000,000 mega watts of power

Hertz Unit of frequency

MW Mega watt is 1 million watts of power

Nimby Not in my back yard

NOx Nitride content in gases

Nuclear Uses an atomic reaction to create power

Protection Electrical apparatus that protects electrical circuits and people from fault currents and voltages

SOx Sulphur content in gases

SSE Scottish and Southern Electricity

Switchgear Electrical apparatus that can switch voltage and current

Transformer Electrical apparatus that can increase or decrease voltage

Volts The electric unit of voltage

Watts (W) Watt is a unit of power



Appendix Appendix 1: Extension Activity Interview Practice – Job Vacancy – Energy Advisor This exercise should give you practice in the technical aspects of a job interview where you may be interviewed by a small group of people. The group will consist of 5 people. 4 students will be the interviewers and the 5th student will be the person being interviewed. This will involve all 5 students ‘investigating’ aspects of the ‘key’ issues for the energy sector. Suggested topics are: • hydro • renewable energy

o wind o wave o tidal

• nuclear power As a result of this, the students will accumulate a bank of interview questions and possible answers. All five students will rotate their roles such that everybody gets an opportunity to be the interviewee. The interview should be formal and be realistic like a real life situation eg. the student would be expected to make a 5-10 minute presentation to the interviewers. This is an opportunity to develop some key aspects of the energy units including: • seeking information • peer evaluation • presentation skills • portfolio collation

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