‘Saving the Planet: and Eco-design Roadshow’

WORKSHOP ACTIVITY BOOKLET

Contents 3. Health and Safety

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4. Introduction to the Environment

5. Peak Oil Production

6. Resource Use

7. Introduction to Renewable Technologies

9. Deconstruction Exercise

14. Wind turbine Exercise

15. Environmental Quiz

18. Solar Transport

21. Make your own biodiesel

24. Making Soap

26. Sustainable Housing

Health and Safety

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Certain rules should be enforced during laboratory sessions to ensure the health and safety of those participating in the activities.

1. No eating or drinking in the labs.2. Always wear a lab coat and safety goggles for

practical work.3. Mobile phones are not to be used in the laboratory.4. Always wear nitrile gloves whilst doing any

chemical work.5. Always read the hazard signs on bottles6. Long hair to be tied back before starting any

practical work.7. Report any breakages or any chemical spills to a

member of staff immediately.8. Rinse your hands under cold water if you spill

anything on them.9. Always wash your hands after doing a chemical

practical.10. Make a visual check of electrical wiring before

using equipment.11. Ask a member of staff to demonstrate if you

are unsure how to use any equipment.12. Refer to specific workshop information for

further health and safety instructions.

Introduction to the Environment

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This workbook deals with several environmental issues that affect us on a global scale. These include global warming (climate change), Peak Oil Production and Consumerism.

Global warming is the increase in the average temperature of the Earth's near-surface air and oceans. Global warming has various natural causes, such as changes in solar output, natural disasters such as volcanic eruptions increasing the amount of greenhouse gases in the atmosphere, and changes in the Earth’s orbit (referred to as Milankovitch cycles). The recent warming of the Earth (by 0.74 ± 0.18 °C in the last 100 years) is attributed to “observed increase in anthropogenic (man-made) greenhouse gas concentrations" via the greenhouse effect.

The greenhouse effect is the process in which the emission of infrared radiation by the atmosphere warms the Earth’s surface. The Earth's average surface temperature of 15 °C (59 °F) is about 33 °C (59 °F) warmer than it would be without the greenhouse effect.

Global warming is believed to be the result of increased concentrations of greenhouse gases in the atmosphere, due to human activity. Greenhouse gases include; water vapour, which causes about 36–70% of the greenhouse effect on Earth, Carbon dioxide, which causes 9–26%, methane, which causes 4–9%, and ozone, which causes 3–7%.

Specific media interest in the levels of CO2 in the atmosphere is not without cause. It is focused upon as it is does not degrade easily in the atmosphere (like other greenhouse gases) so will be around longer. It also has a high rate of radiative forcing, so has a higher potential for warming.

Peak Oil Production4

Peak oil is the point in time at which the maximum global petroleum production rate is reached, after which the rate of production enters its terminal decline. If global consumption is not mitigated before the peak, the availability of conventional oil will drop and prices will rise, perhaps dramatically. High dependence of most modern industrial transport, agricultural and industrial systems on the relative low cost and high availability of oil will cause negative implications for the global economy.

Liberal estimations of peak production forecast a peak will happen in the 2020s or 2030s, whilst more conservative predictions of future oil production operate on the thesis that the peak has already occurred or will occur shortly and, as proactive mitigation may no longer be an option, predict a global economic depression. The CEO of Total Oil predicts that peak oil production will occur in 2013.

The transportation sector sees the highest annual growth in petroleum, and it is estimated that cars and trucks will cause almost 75% of the increase in oil consumption by India and China between 2001 and 2025, as more people will be able to afford personal vehicles, if current trends continue. Transportation accounts for approximately 69% of the oil used in the United States in 2006, and 55% of oil use worldwide.

As crude oil production decreases, it is thought by some that economic meltdown can be mitigated by using existing technologies such as post-production of bitumen (left) to produce a fuel that will run a car. These have their own drawbacks - as well as

being more expensive, they also emit 3 times as much greenhouse gases in their production and use.

Resource Use

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The world’s resources are being used at a spectacular rate, especially fossil fuel resources, but also metal ores, precious stones, forestry resources and habitats.

It is estimated that almost two-thirds of the natural machinery (rainforest, coral reefs, etc.) that supports life on Earth is being degraded by human pressure on the environment through deforestation (above) for industry. More land has been taken from old forest for agriculture and fuel growth in the last 60 years than in the 18th and 19th centuries combined. It is now estimated that 24% of all land is cultivated.

Another major problem is that resources are used mainly by western, developed, countries, creating a massive discrepancy between these high consuming nations and the low consuming nations of the developing global south. It is estimated that a child born in New York, Paris and London will consume, pollute and waste more in their lifetime than 50 children born in a developing country. It is approximated that a

fifth of the world’s population is responsible for 90% of its consumption.

It is this discrepancy in resource use that leads to a huge wealth gap between the developed and developing countries. It is estimated that the 200 richest people in the world have a combined income of the poorest 47% of the Earth’s

population, equivalent to 2.5 billion people.

This huge resource use by the richest nations is having an irreparable effect on the environment. 12% of the world’s total birds, equivalent to 1183 species, and a quarter of mammals (1130 species) are threatened by extinction, brought about by increased human pressure on the environment. It is estimated that 80% of Europe’s lakes are polluted by the overuse of petrochemical fertilisers (above). And as noted above, the burning of fossil fuels and subsequent release of greenhouse gases is causing global warming by enhancing the greenhouse effect. Radical change would need to be implemented in the fuel sector to avert disaster as the world demand for oil is set to increase 37% by 2030, promising more negative impacts on the environment if the supply is available and used.

Introduction to Renewable Technologies6

Due to the dual threats of climate change and peak oil, it becomes apparent that there is a need for change in how energy is produced and used. This section explores the alternative sources of energy to conventional fossil fuels. Wind Power – The UK in particular is well suited to using wind turbines to produce energy, with a third of Europe’s offshore wind resource. Offshore wind is more expensive and leads to higher energy yields than onshore wind. The Centre of Alternative Technology (CAT) predicts that if Britain was to ever be carbon-neutral, up to 50% of our electricity would have to be sourced from offshore wind.

Photovoltaic Electricity – Producing electricity from solar energy. The UK may not seem ideally suited to using PV technologies, but efficiency of PV cells are improving rapidly and costs are coming down due to economies of scale in production.

Biodiesel – Generating electricity from the burning of chemically altered plant oils. Waste Vegetable Oil can be used as a feedstock to avoid importing exotic oils. It is estimated that the WVO in the UK could provide fuel for 1-2% of car use.

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Tidal Power - Tidal energy is the result of the sun and the moon’s gravitational pull on the tides. When the Earth rotates, the tides move – ebbing and flowing. The change in the water level between high tide and low tide creates tidal currents in coastal areas, which can be forceful enough to drive a turbine and generate electricity. It is especially relevant for the UK, with its vast coastline.

Nuclear Power – nuclear fission already provides 20% of the UK’s energy needs, set to decrease as aging reactors are shut down. The UK government is currently deciding on whether or not to build a new nuclear generation. Nuclear does not directly produce CO2 but indirectly produces a lot of CO2 in construction. Nuclear is a good source of baseline energy, but produces radioactive waste which will have to be kept safe for many generations to come.

Vehicle to Grid SystemsThe Centre for Alternative Technology (CAT) suggests in their outline of a sustainable Britain (zerocarbonbritain) that a Vehicle to Grid (V2G) could provide the baseline energy requirement in a situation where nuclear power doesn’t exist. Electrical vehicles, rather than being an extra burden to the grid, become a much needed way for grid managers to balance the amount of energy

generated at any given time to match the amount of energy being consumed. Millions of cars, each with several kilowatt hours of storage capacity, would act as an enormous buffer, taking on charge when the system temporarily generates too much power, and giving it back when there are short peaks in demand. The V2G system eliminates the need for nuclear power to act as a baseline provider and therefore reduces the burden of radioactive waste being produced.

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Deconstruction Exercise

It is claimed that 93% of all production material is never used in the final material of a product. 80% of all products are discarded after a single use. This represents a huge waste of resources. Through deconstructing everyday household objects, such as kettles and telephones, you can see every component that is used, and get an idea about how these items work. You can gain an idea about how easily the item is repaired, recycled and how it will enter the waste stream.

Designing a product using the concepts of Eco-Design and sustainable development can significantly reduce the impact that product has on the environment. Designing sustainably means you have to take into account 3 factors: the environment; the economy; and society. Eco-design, as opposed to traditional design looks at the effects on the

‘triple bottom line’ of environment, society and economy of materials extraction. As well as looking at the cost-effectiveness of materials extraction, designers would look at whether a material was mined, grown or otherwise obtained, and what the impacts are on the environment. The designer would also take into

account the effects on society that these processes are taking. For example, is it harming traditional cultures? Does it help bring about positive social change?

Eco-Design should take into account the preferred Waste Hierarchy (right) of Sustainable development. Waste should preferably be reduced at source, by thinking about ways to reduce that 93% of production waste mentioned earlier. The next emphasis should be on how

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easily the product is to re-use, reducing the 80% of waste from single-use items. This should preferably be taken into account during the design stages of manufacture, so that a product is easily able to be used more than once. Then, focus should be placed on how easily the product is to repair, and how cost effective this would be for the consumer.

The next point to think about would be how easily the product is to recycle. This would take into account issues such as separation and contamination of materials, materials type and whether adequate recycling infrastructure is in place in the market.

This should reduce the materials ending up in the conventional waste stream (i.e. landfill and incineration) considerably.

A number of adverse impacts occur from landfill operations. Including infrastructure damage, pollution of the local environment by contamination of groundwater and aquifers by leakage and residual soil contamination after landfill closure, the release of methane ( a greenhouse gas) generated by decaying organic wastes; harbouring of disease vectors such as rats and flies, injuries to wildlife and noise pollution.

Some local authorities have found it difficult to locate new landfills. This is a particular problem in the UK, where authorities may charge a fee or levy in order to discourage waste and recover the costs of site operations. An eco-designer will look to reduce pre-production waste as much as possible to avoid paying the landfill levy as well as reducing the impact on the local environment.

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The Deconstruction Task

Equipment NeededScrewdriver s (Philips and flat bladed)PliersSafety GogglesSafety GlovesPenPaper

Task

Before you start taking the product apart, answer these questions:

1. What is the name of the product you are going to take apart?

2. What is the product’s primary function?

3. What are the product’s secondary functions?

4. Can you tell how much the product cost? (If not, guess)

5. What is the target market for the product?

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Health and Safety

As well as observing the other Health and Safety regulations (listed above):

Always wear safety goggles and gloves when doing this practical.

If you are unsure how to use a piece of equipment, ask a member of staff.

Now, carefully take apart you product.

6. How easy it is it to take the product apart?

7. List all the different components of the product. How many components are there?

8. Make a list of all the different materials used in the product.

9. How many different materials were used in the product?

10.Are the different materials easily identified? (i.e. by using identification symbols – right )

11. How easy would it be to get the product repaired?

12.Would it be cost effective to get the product repaired?

13.How easily could the various components be recycled?

14. Would you say that the product was designed using the principles of eco-design? Why?

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Now you have taken apart the product and answered the questions, consider how you could design the product to make it more sustainable. Write your ideas down under each heading.

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Product Function

How could you change the function of your product to make it more sustainable? (i.e. for a kettle, could you design it so it could not be over-filled, and therefore waste energy? )

Accessibility

How could you change the product to make it easier to be taken apart, so it can be repaired or recycled?

Choice of Materials

Could you change the materials used in the product to make it more durable? More easy to recycle? More sustainable? Remember to keep in mind the original function of the product, and that the material must be appropriate for that use.

Draw a diagram of your altered product below

Wind Turbine Exercise

A major criticism of the use of wind turbines in the UK is that they cannot be used practically in areas where the average wind-speed is below a critical threshold. By measuring the wind-speed and the power generated by a wind turbine in a lab situation, we can estimate where this critical threshold is and then determine whether a given area is suitable for wind turbine placement.

Health and Safety

As well as observing the other Health and Safety regulations (listed above):

Always wear safety goggles when doing this practical.

If you are unsure how to use a piece of equipment, ask a member of staff.

Stay clear of the rotating blades of the wind-turbine. If possible, build a cage around the turbine before the experiment.

You may be using loud machinery in this practical. Make sure that you wear safety ear muffs.

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Equipment Needed

Computer with internet access

Model wind turbine

Anemometer

Fan with multiple speed settings

(or, alternatively a fan attached to a Triac power controller)

Paper

Pen

Multi-metre

Resistant load

Safety ear muffs

Before you start the practical, produce a table with ‘Wind-speed (m/s)’, ‘Voltage’, ‘Resistance in ohms’,’ Amps’ and ‘Power in watts’ as headings, such as the table below. There should be enough rows to do up to 30 readings.

Wire up the wind turbine to the resistant load and the multi-metre and then measure the resistance in the load. This resistance should stay constant throughout the entire practical, so you can fill it in along the entire Resistance column of your table.

Place the fans so they are facing the wind turbine. Put them on the highest setting and measure the wind-speed using the anemometer, in metres per second. Fill this number in the Wind-speed column. The blades of the turbine should be turning. Using the multi-metre, measure the voltage coming off the wind turbine, and fill this number in the voltage column.

You can then work out the amps coming off the wind turbine by using Ohm’s Law.

Where I=current (amps)

V=Voltage

And R=Resistance in ohms.

Once you have found the current in amps, you can work out the power using the following equation:

P = V.IWhere P = power.

The . symbol when used here denotes multiplication.

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Continue doing this for each setting on your fan. If you are using a triac and can control the amount of power going into the fans, we recommend that you take measurements in increments of 5 volts going into the fans.

After collecting your data, produce a graph of Power vs. Wind-speed.

Now you can plot onto your graph the average wind speed of your area and find out how much power you will produce using the wind turbine you have used. To find out the average wind-speed of a given place, log onto

http://www.renew-reuse-recycle.com/noabl.pl?n=503

Type in your desired postcode. The programme will then produce the average wind-speed in your area at given heights. Plot them onto your graph and see how much power you would be able to get out of them.

1. How much power do you get out of your wind turbine in your area at the given heights?

2. Would it be financially viable to put a wind turbine in that area?

3. Engineers believe that the critical wind-speed threshold of viability for wind turbines is about 6 meters per second. How does that compare with the data you have collected?

4. Why might the experiment you have just conducted be unreliable?

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Environmental Quiz

1. A car driver switching to the train or bus may cut their pollution by up to...a) 95%b) 56%c) 72%

2. How much oil does recycling one ton of recycled office paper save? a) 12 gallons b) 512 gallonsc) 380 gallons

3. Which is true about batteries? a) Batteries produce 50 times less energy than it takes to make themb) Batteries produce 20 times more energy than it takes to make themc) Batteries produce the same amount of energy as it takes to make them

4. How much, per year, can switching one 100 watt light bulb to energy saving bulbs save you? a) 50 penceb) £5.10c) £10

5. How much of the UK’s energy is used in transport? a) A fifthb) An eighthc) A third

6. Aviation generates as much carbon dioxide as: a) Africab) Leichtenstienc) Nepal

7. What percentage does lighting make up of your household electricity bill? a) 25%b) 15%c) 5%

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SOLAR POWERED TRANSPORT A solar PV cell is a semiconductor that converts light from the sun to electricity. The energy in the photons is transferred to electrons in the PV cell, releasing them from their respective atoms. PV cells have electrical fields that pull the freed electrons in a certain direction, creating an electronic current. This process is known as the Photovoltaic Effect.

Solar photovoltaics are the world’s fastest growing energy technology, increasing in production by 48% each year since 2002. Solar photovoltaics provided 0.04% of the world's Total Primary Energy Supply (TPES) for the year 2004, at a rate of growth to reach 0.08% by the end of 2006.

The amount of electricity produced by solar PV cells is dependant on the amount of solar radiation. The map (left) shows

the annual sum of irradiation on optimally inclined south orientated PV modules, with the darker, redder areas producing more electricity than the cooler blue areas.

Life cycle greenhouse gas emissions for PV cells are now in the range of 25-32 g/kWh, set to decrease to 15

g/kWh, as opposed to a gas-fired power plant emits some 400 g/kWh and a coal-fired power plant 915 g/kWh. Nuclear power produces 25 g/kWh whilst wind power produces 11g/kWh, the least amount of all available energy technologies.

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SOLAR POWERED CAR PROJECT

The electricity produced by solar PV cells can be used to power a vehicle via an electrical motor. In this task, you will build a solar powered car to demonstrate the use of PV technology.

Firstly, you need to think about a few key issues:

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Chassis design.

A strong but lightweight design is needed to hold the solar panels. Draw your detailed chassis design below.

Wheels

It is important to consider the effect of friction and torque on wheels. Draw your chassis and axles, connected to your chosen wheels below.

Other tips

Keep the mass of the car to a minimum to reduce the downwards dragging force.

The higher the solar panels are, the closer they are to the light source. This may affect the amount of energy they produce.

An aerodynamic design will reduce the air resistance and allow your car to move faster.

Solar Powered Car Assembly

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Health and Safety

1. Wear safety glasses when using knives

2. Cut away from yourself when using knives

3. Keep hands away from cutting area when using hacksaws

4. Be cautious when using glue guns, as the glue is very hot

Power

Attach your wired up solar panel to a voltmeter and ammeter. These will measure the voltage and the current, respectively. From this, you can find out the power generated by using this formula:

Power = Current x Voltage

Work out the power generated by your solar panels below:

Assembly

Build the car frame out of the materials provided.

Assemble the electric motor and wire to the solar panels.

Select wheels and add them on to the car.

Add the solar panels and motor onto the car.

Decorate the car as desired

Test car and make adjustments, if needed.

The Race

Points should be awarded for:

The best decorated car

The most efficient car

The fastest car

The best designed car

The most sustainable car

The panels with the most power

BiodieselBiodiesel is a term for diesel-equivalent fuel consisting of short chain methyl esters, made by trans-esterification of vegetable oils or animal fats, which can be used (alone, or blended with conventional diesel fuel) in unmodified diesel-engine vehicles. Biodiesel (left) has the advantage of being completely non-toxic and biodegradable. It also produces 60% less net-carbon emissions than conventional diesel fuels. Its other environmental benefits include a reduction in hydrocarbon and toxic organic micro-pollutant emissions.

Biodiesel has many other performance related benefits. It is considered a better solvent than conventional diesel and removes deposits trapped in the fuel lines. It does, however, sometimes cause blockages in the fuel injectors if the engine has previously ran on conventional diesel. This means that a car running on biodiesel may have to have its fuel filter changed more often than usual. This is a particular problem in common rail vehicles (left). Biodiesel is cheaper than conventional diesel in this current economic climate. A litre of biodiesel can be produced for about 20 pence, and no tax is payable on this unless the manufacturer is producing more than 2500 litres of biodiesel per year. In the current economy, where prices exceed a pound per litre, the use of biodiesel can mean significant cost savings.

MAKING BIODIESEL21

Biodiesel is made from vegetable oils using the trans-esterification process.

Triglyceride (veg oil) + Methanol → methyl esters (biodiesel) + glycerol

This process requires a catalyst of either Sodium hydroxide (NaOH) or Pottasium hydroxide (KOH).

When using fresh vegetable oil, a standard 9 grams of KOH (left) is used to neutralise the oils. Using Waste Vegetable Oil provides its own problems. Because the oil has been heated up before, some of the triglyceride molecules get split into Free Fatty Acids (FFA’s). This increases the acidity of the oil, and so more KOH is needed to neutralise the mixture. To find out how much KOH we need to use, we need to perform a titration.

Titration

1. Mix 1 gram KOH with 1 litre of distilled water. 2. Mix 10ml of isopropyl alcohol with 1ml of WVO, and a few drops of

universal indicator. This will be the test sample.3. Use a calibrated pipette to measure out 1ml of the KOH solution 4. Slowly drop the KOH solution into the test sample, monitoring how

much KOH solution you add5. Stop when the colour changes to indicate a pH value of around 8.6. Using the equation below, find out how much extra KOH you need

to add.

Added KOH per litre = drops added / drops per ml

Biodiesel Production22

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Health and Safety

Always wear gloves and goggles during this procedure

Do not smoke near the methanol, it is highly flammable, and will auto-ignite under relatively low temperatures.

KOH is violently caustic. Keep a squeezy bottle of vinegar around to neutralise the alkali should a spillage occur.

The biodiesel reaction takes a few stages to implement. The first is making methoxide.

Making Methoxide

1. Mix 200ml of methanol for every litre of oil.

2. Add the correct quantity of KOH worked out from the titration.

The Reaction

The second stage of the process.

1. Add the methoxide to the oil

2. Heat the oil mixture to 45˚C, being sure to keep the temperature below 65˚C, as this is the temperature at which methanol evaporates.

3. Keep on the heat for 10- 20 minutes.

4. Leave the container overnight and the glycerol should settle to the bottom of the container

5. Remove the glycerine from the biodiesel.

6. The biodiesel can now be washed, before putting in a vehicle.

Washing and Drying

The final stage of the process before the biodiesel can be used in a vehicle.

Biodiesel can be washed in many ways. Some people prefer to use the bubble-washing technique where air is bubbled through the mixture, taking out the impurities with it. Others prefer to gently mix water with the biodiesel, washing away the impurities.

Soap Making

The movie ‘Fight Club’ cast Brad Pitt as a soap-maker who made soap out of stolen human fat from liposuction. In a similar way, we will be making soap out of glycerine. Glycerine is formed as a by-product of the trans-esterification reaction that makes biodiesel.

Glycerine is often used in cosmetics, as it moisturises the skin. Commercial soap manufacturers tend to remove the glycerine for use in lotions and creams, which are more profitable.A higher price is charged for handcrafted soaps, which retain the glycerine.

Pure glycerine is completely clear, odourless and non-toxic. The glycerine from the biodiesel is contaminated with other products, and so is a dark brown colour. For use in soap making, the glycerine needs to be purified by removing the methanol and other products.

To remove the residual methanol, boil the mixture over an open flame. Do this is an open, highly ventilated space and do not breathe in the fumes. The glycerine mixture still contains residual potassium hydroxide, or residual sodium hydroxide, and so is still caustic. It is important that you wear gloves when handling this product.

Making soap from glycerine is known as saponification. It can be used for all sorts of purposes, from hand washing, to laundry, to cleaning machine parts.

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The saponification process must use the same catalyst as used in the biodiesel reaction. Sodium hydroxide (NaOH) will yield a solid soap, and Potassium hydroxide (KOH) will yield a more liquid soap.

For KOH :Use 100ml of water per 1 litre of glycerine.

1. The amount of KOH needed is dependent on how much was used in the trans-esterification reaction and the purity of KOH used. Work out how much KOH to use in the saponification reaction by:

Multiplying by 1.52 for 92% pure KOH usedMultiplying by 1.56 for 90% pure KOH usedMultiplying by 1.65 for 85% pure KOH used

2. Mix the extra KOH with the water.

3. Gently heat the glycerine and add the KOH solution.

4. Mix for approximately 15 mins, adding any essential oils, colours you need. Pour into you mold and leave to cure for about 2 weeks before use.

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Sustainable Housing

Much focus is put on sustainable house design today, by engineers and the media. The UK government has committed to ensuring that all new-build houses are carbon-neutral. Sustainable housing is often referred to as ‘Green Building’. Green building is the practice of increasing the efficiency of buildings, especially in the context of resource use. This includes energy, water, and materials. Green building techniques aim to reduce the negative impacts on the environment. The siting, design, construction, use, repair, and demolition of the building are all considered.

Heat loss in domestic buildings is an especially big issue within the construction industry. In an uninsulated house, 25% of heat is lost through the roof, 35% out of the walls, 10% out of the windows, 15% out of the floors, and the final 15% out of draughts. Cavity wall and roof insulation can make a big difference in saving energy with the home.

The choice of materials used in construction also affects how much heat is lost. Different materials have different thermal performances, measured by a U-value. This U-value, once known, can be used to work out the rate of heat loss from buildings, and so compare the efficiency of different materials at keeping heat inside the house.

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SUSTAINABLE HOUSING EXERCISETo compare different building materials for their thermal properties, you are to make a house out of lego bricks. The house must be a 6 x 6 x 6 meter cube. The total area for windows will be 12m2 and the total area for external doors should be 4 m2. Otherwise the house can be of any design.

Each lego brick colour has a different U-value, and a different cost.

Red has a U-value of 0.1 Wm-2 and a cost of £5 per brick

Green has a U-value of 0.5 Wm-2 and a cost of £3 per brick

Blue has a U-value of 1.0 Wm-2 and a cost of £1 per brick

Windows have a U value of 5.6 Wm-2 and are free

Doors have a U value of 3.5 Wm-2 and are free

The house has a air change rate of 1 ach.

Points will be awarded for:The cheapest house to heat

The most efficient house

The cheapest house to build

Build your houses

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Step 1.

Work out the fabric loss of the walls. Assuming that

Fabric loss= U-value x area x temperature difference

Take the inside temperature to be 20˚C and the outside temperature to be 5˚C

Step 2.

Work out the Fabric loss for the doors and windows

Step 3.

Work out the ventilation losses of the house using this formula:

Ventilation loss = 0.33 x house volume x air change rate x temperature difference

Step 4.

What is the total heat loss?

Total Heat Loss = Fabric Loss + Ventilation Loss

Step 5.

Assuming that the house is left for 1 hour, and that 1kWh of energy is £1.50, how much money does the own loose over the hour?

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