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EYEManager Guide

A helpful tool for the European Young Energy Managers!

This Training Guide, the EYEManager Guide, aims to be a helpful tool for

improving the secondary level schools students – who they will become this

way the European Young Energy Managers - basic knowledge on:

- Energy-using products and the most energy-intelligent ways to install and

use them;

- Energy saving behaviours, which counsel the students in the adoption of

energy saving skills in their daily life;

- The Energy Auditing Method, i.e. how to collect data concerning energy

consumption, CO2 emissions and energy efficiency of the building, its

plants and equipments;

- The way to draw-up Energy Saving Plans, which guides the students in the

individuation of practical interventions to improve the energy performance

of the analysed case studies and to estimate the costs related to the

implementation of the different solutions and the related impacts in terms

of economic savings.

The EYEManager Guide has not to be seen as a recipe to be followed.

Instead, it aims to clarify and explain the basic concepts needed for an energy

auditing process and for energy efficiency improvements. It was developed in

the frame of the “European Young Energy Manager Championship - EYEManager Championship” Intelligent Energy-Europe Project (Contract Nr:

IEE/07/760/SI2.499406) and consists only a part of the EYEManager Toolkit composed by:

1. The EYEManager Guide (a practical guide for European Young Energy

Managers).

2. The EYEManager Championship Managerial Software (and user

manual), which is a web based application that will support the EYE

Managers in the analysis of the study cases and in the design of the Energy

Saving Plans.

3. The EYEManager Championship rules, which define in full detail all

aspects related to the International Championship, and in particular the

composition of the International Teams, the Championship’s phases, the

Scores and the Awarding criteria.

The sole responsibility for the content of this publication lies with the authors. It does not

necessarily reflect the opinion of the European Communities. The European Commission is not

responsible for any use that may be made of the information contained therein.

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CONTENTS

1. INTRODUCTION...................................................................................... 5

1.1 The combined Energy-Environmental problem .................................. 5

1.2 Buildings’ energy use ........................................................................ 6

1.3 Potential for improvements............................................................... 8

2. ENERGY MANAGEMENT ........................................................................... 9

2.1 Energy management as a continuous process ................................... 9

2.2 Energy Management Action Plan ..................................................... 10

2.3 Energy Monitoring ........................................................................... 12

3. ENERGY EFFICIENCY IN BUILDINGS..................................................... 13

3.1 Energy-using products .................................................................... 14

3.2 Energy Conservation Measures........................................................ 16

3.2.1 Building envelope ..................................................................... 16

3.2.2 Heating and Cooling.................................................................. 17

3.2.3 Domestic Hot Water .................................................................. 21

3.2.4 Lighting..................................................................................... 22

3.2.5 Domestic appliances ................................................................. 24

3.2.6 Office equipment....................................................................... 26

3.2.7 Renewable Energy Systems ...................................................... 26

3.3 Energy Saving Behaviours ............................................................... 27

4. ENERGY AUDIT ..................................................................................... 30

4.1 Types of Energy Audits.................................................................... 30

4.1.1 Walk-through Audit................................................................... 30

4.1.2 Utility Cost Analysis .................................................................. 30

4.1.3 Standard Energy Audit .............................................................. 31

4.1.4 Detailed Energy Audit ............................................................... 31

4.2 Energy Surveys ............................................................................... 32

4.3 Data collection on the Energy Use ................................................... 33

4.3.1 Data from invoices .................................................................... 33

4.3.2 Data from meters...................................................................... 34

4.4 Data Analysis .................................................................................. 35

4.4.1 Energy consumption ................................................................. 35

4.4.2 Performance indicators ............................................................. 35

4.4.3 Energy time-charts ................................................................... 36

4.4.4 Energy balances........................................................................ 37

4.5 Drawing up of Energy Saving Plans ................................................. 39

4.6 Economic analysis of Energy Retrofit Projects................................. 39

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4.7 Report writing and results communication...................................... 40

5. BEST PRACTICE .................................................................................... 42

5.1 Step-by-step procedure for a Standard Energy Audit ...................... 42

5.2 Case study: Nautical School ............................................................ 45

5.2.1 Background .................................................................................. 45

5.2.2 Description of the site .................................................................. 45

5.2.3 Description of the work ................................................................ 46

5.2.4 Outputs of the Energy Audit ......................................................... 47

BIBLIOGRAPHY ........................................................................................ 51

ANNEX 1 ................................................................................................... 52

ANNEX 2 ................................................................................................... 53

ANNEX 3 ................................................................................................... 54

List of abbreviations

CFL: Compact Fluorescent Lamp

DHW: Domestic Hot Water

EC: European Commission

ECM: Energy Conservation Measure

ECO: Energy Conservation Opportunity

EMCS: Energy Monitoring and Control Systems

EU: European Union

HVAC: Heating, Ventilation and Air-conditioning

LCC: Life Cycle Costs

LPG: Liquefied Petroleum Gas

RES: Renewable Energy Sources

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1. INTRODUCTION

1.1 The combined Energy-

Environmental problem

Energy use facilitates all human

activities, as well as social and

economic progress. The magnitude of

energy consumed per capita has

become one of the indicators of

modernization and progress of a

country. Thus, countries all over the

world consider the production and

consumption of energy as one of their

major challenges. At the same time,

energy is directly related to the most

pressing social issues that affect

sustainable development (poverty,

health, jobs, population growth, access

to social services, land degradation,

climatic changes and environmental

quality, etc.).

The final forms of energy that are

available for use (electricity, LPG,

gasoline) are produced from primary

energy forms that exist in nature, like

coal, natural gas and oil. These are

called “fossil fuels”. Their use

generates Greenhouse Gas emissions

such as Carbon Dioxide (CO2), which is

responsible for the 75% of these

emissions. These gases enhance the

Earth’s natural greenhouse effect

(Figure 1.1), rising the planet’s

average temperature and therefore

producing serious and unpredictable

climate phenomena.

Figure 1.1: The Greenhouse Effect

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Besides this problem, conventional

energy resources (i.e. fossil fuels) are

progressively exhausted (according to

recent studies, the known oil, natural

gas and Uranium deposits will last no

more than 40 years), and the energy

costs, in general, become higher and

higher. The families have to pay more

for the energy they use, which most of

the times is not used efficiently.

The adverse impacts of energy

production and consumption can be

mitigated either by reducing

consumption or shifting energy

supplies to options better able to

support sustainable development.

Technological change has by far the

greatest potential than changes in the

patterns of consumption of goods and

services. However, such an

assessment must not preclude

attempts to shift away from irrational

and wasteful patterns of consumption.

In a next step, when all possibilities for

saving energy have been examined

and applied, it is the time to consider

the possibility of exploiting Renewable

Energy Sources (RES). RES are

increasingly important as sustainable

alternative energy sources. They

generate less environmental impacts

and, mainly, they do not produce

Greenhouse Gas emissions, while they

contribute a lot to the safety of energy

supply. Solar energy (for heat or

power generation), wind energy,

hydropower, bioenergy, geothermal,

marine energy, are just few of them.

1.2 Buildings’ energy use

The 160 million buildings in the EU use

almost 40% of Europe’s energy and

create over 40% of its CO2 emissions,

and that proportion is increasing.

Moreover, this is higher than the share

of industry and transport (see Figure

1.2 – Note: by “services” the buildings

of the tertiary sector are meant).

Households consume the two-thirds of

the energy used in buildings.

Figure 1.2: Final Energy Consumption in EU27 by sector (Mtoe1)

1 1 Mtoe stands for 1 million tonnes of oil equivalent (toe), and is a unit of energy: the amount of energy released by burning 1 tonne of crude oil, approximately 42 GJ.

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Space heating is the most important

component (57% of domestic and 52%

of the non-residential buildings

consumption). It is important to

mention that, the use of fuel for

heating buildings amounts to 25% of

the total CO2 emissions in the EU.

Water heating accounts for 25% of the

domestic consumption and 9% of non-

residential use.

Lighting consumes around 4% of total

energy in the residential sector (about

9 Mtoe), while in the tertiary sector,

where the large majority of lighting is

provided by fluorescent lamps, lighting

consumes around 18 Mtoe, or 14% of

the sector's energy. Another important

aspect is that lighting accounts for up

to 25% of the emissions due to

commercial buildings.

Air-conditioning is a rapidly growing

consumption activity in the residential

and tertiary sectors. The total energy

consumption for air-conditioning is

about 3 Mtoe (0.7% of total final

energy consumption in the two sectors

combined), and this is expected to

double by 2020. Graphically, the

energy consumption by end-use in EU

buildings (according to data of 2000)

is provided in Figure 1.3.

Spaceheating

52%

Cooking5%

Lighting14%

Cooling4%

Other16%

Waterheating

9%

Space heating

57%

Water heating

25%

Cooking7%

Lighting & Appliances

11%

Figure 1.3: Energy consumption by end-use in EU tertiary (left) and residential

(right) buildings

Figure 1.4: Final energy consumption in EU27 by fuel (in Mtoe)

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Currently, most of the energy used in

the built environment is derived from

non-renewable fossil fuels. As it shown

in Figure 1.4, oil, natural gas and solid

fuels count form more than 70% of the

final energy consumed in the EU, while

RES are still contributing in very low

percentages.

1.3 Potential for improvements

There is indeed significant potential in

improvement of buildings’ energy

consumption, taking for example into

consideration that the total energy

consumed in new buildings is

estimated to be the 60% of that used

in buildings constructed during the

‘70s. According to the European

energy commissioner, a cost-effective

savings potential of around 22% of

present consumption in buildings can

be realized by 2010.

Some interesting tips:

� Boilers: 10 million EU residential

boilers are older than 20 years.

Their replacement would save 5%

of the heating energy.

� Lighting: 30-50% savings could be

achieved with the use of the most

efficient components, control

systems, integration of day-lighting

and other technologies.

� Cooling: Energy use for air-

conditioning will double by 2020.

25% could be saved through air-

conditioning equipment minimum

efficiency requirements.

� Green energy generation: On-

site RES, cogeneration of heat and

power, connection to district

heating/cooling and heat pumps

also have savings potential.

� Bioclimatic design: Active and

passive solar design and systems,

improved day-lighting and natural

cooling can reduce energy demand

by up to 60%.

A better situation can be achieved

through the proper Energy

Management of the facilities (i.e. the

management of the energy demand of

those facilities). Indeed, with the

improvement of end-use energy

efficiency, by providing the same

energy service with less energy inputs

or achieving more energy services with

the same energy input, specific energy

consumption can be reduced by 20-

50% in the case of improvements in

existing energy using installations, and

50-90% in the case of new

installations.

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2. ENERGY

MANAGEMENT

Being economically competitive in the

global marketplace and meeting

increasing environmental standards to

reduce air and water pollution have

been the major driving factors in most

of the operational cost and capital cost

investment decisions for all business,

industry or government organizations.

Energy management has been an

important tool to help organizations

meet these critical objectives. Energy

management may be defined as the

control of energy flows through a

system, so as to maximize the net

benefits to the system. It involves the

collection, analysis and monitoring of

information on energy use, and the

identification, evaluation and

implementation of energy saving

measures (E.C., 1995).

There are many good reasons to

manage energy, starting from the fact

that good energy management in

buildings can reduce both energy costs

and environmental damage. In

addition, many energy problems are

linked to service problems. Fixing

these problems has the spin-off effect

of improving the quality of the working

environment, which will increase staff

morale and productivity. The effects of

this can multiply the energy savings

tenfold.

2.1 Energy management as a

continuous process

There are different levels on which the

energy relevant activities can be

planned and implemented. On one

hand, there are comprehensive energy

planning concepts (energy

management action plans), which

usually include the following parts:

� well defined objectives,

� analysis of the current situation,

� analysis of possible measures and

scenarios,

� definition of actions and projects,

� implementation and evaluation.

On the other hand, there is the

possibility of implementing single

measures that are not connected or

embedded in a comprehensive energy

planning concept. The idea is to

identify and compare different

measures only very roughly without

collecting a pile of comprehensive data

and without designing a whole action

plan. Rather only a single measure can

be selected and implemented as a

single project right away.

It must be emphasized that energy

management is a long-term

commitment, not just something that

is carried out once and then passes

through. If the energy manager has

implemented the review stage of the

action plan properly, then a plan of

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continuous improvement has already

been instituted. However, the need for

continuous improvement is high.

According to the ENERGY STAR

Programme, initiated by the U.S.

Environment Protection Agency (EPA),

for setting up a successful Energy

Management programme 7 Steps

should be followed:

• STEP 1 - Commit to Continuous

Improvement: The basic element

of successful energy management is

commitment. Organizations make a

commitment to allocate staff and

funding to achieve continuous

improvement.

• STEP 2 - Assess Performance: It

is the periodic process of evaluating

energy use for all major facilities

and functions in the organization

and establishing a baseline for

measuring future results of

efficiency efforts.

• STEP 3 - Set Goals: Well-stated

goals guide daily decision-making

and are the basis for tracking and

measuring progress. Communicating

and posting goals can motivate staff

to support energy management

efforts throughout the organization.

• STEP 4 - Create Action Plan: A

detailed action plan should be used

to ensure a systematic process to

implement energy performance

measures. The action plan is

regularly updated, most often on an

annual basis, to reflect recent

achievements, changes in

performance, and shifting priorities.

• STEP 5 - Implement Action Plan.

• STEP 6 - Evaluate Progress:

Evaluating progress includes formal

review of both energy use data and

the activities carried out as part of

the action plan as compared to the

performance goals.

• STEP 7 – Recognition of the

Achievements: Providing and

seeking recognition for energy

management achievements is a

proven step for sustaining

momentum and support for the

program.

2.2 Energy Management

Action Plan

An energy management action plan

has to include, as a minimum, the

following components:

1. Well defined goals.

2. Management reporting structure.

3. Resource requirements, both

internal and external.

4. Financial investment criteria.

5. Activities plan.

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6. Energy consumption monitoring and

targeting arrangements.

7. Monitoring and targeting

arrangements.

8. Staff engagement and reporting

structure.

9. Development of a Training Plan (for

staff – occupants).

Many people think an energy

management program starts and ends

with an energy audit. This is partially

true because, although the audit is a

key step, it is by no means the only

step in an energy efficiency program.

Implementing an energy audit’s

recommendations requires persistent

management over a period of years;

and this will pay dividends that will

increase every year. In addition, after

the first comprehensive energy audit

that has to be made in the facilities, a

system for ongoing monitoring should

be put in place, and more targeted

audits should be carried out over time.

The output of the energy audit is a

detailed action-plan for the in-time

implementation of the proposed

energy efficiency measures, based on

the time-programming principles. This

planning should be made for each

phase of implementation and includes:

• the targets and the measures that

have to be implemented in each

phase,

• the time-schedule of each phase,

• the requested organization and the

budget for the implementation

costs,

• the determination of the way that

the progress of work will be

monitored,

• the delimitation of the monitoring/

measuring or/and evaluation of

each phase results procedure.

For the determination of each phase’s

energy related targets, the energy

savings expected to result from the

previous phase of implementation

should be taken into account. As a

result, each phase’s targets should be

posed in respect to the objective

consumption of the previous phase,

and not in respect to the initial energy

situation of the site. A common

criterion for the delimitation of these

targets is that each phase should

secure such benefits for the enterprise

that they will justify both the

investment required for the

implementation of the measure and

the continuation of the energy savings

action-plan.

As a conclusion, it has to be mentioned

that, for drawing-up an energy savings

action-plans the following items have

to be taken under consideration:

a) the scaling of the proposed

measures, as this results from the

energy audit;

b) the combination of the various

energy retrofit projects, as well as

their co-ordination with other

targets of the enterprise;

c) the organizational level and the

technical capability of the

enterprise to implement each one

of the proposed measures or

bundle of measures;

d) the financial capability of the

enterprise to self-finance the

investments required for energy

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efficiency projects, in respect to

other priorities that might have.

2.3 Energy Monitoring

A more efficient energy use is based

on a better knowledge of the energy

use. Therefore, it is crucial to keep an

energy management system that

continuously monitors, analyzes,

verifies and communicates energy con-

sumption, this way improving energy

efficiency. This is the so-called energy

monitoring task, which must be

continuous and focus on energy

consumptions and costs, and has to

cover all different energy forms used

(electricity, fuels, district heating,

others).

A global inventory of energy consu-

ming equipments must be available

and continuously updated. This must

include the type of equipments, their

function, location and power. Regular

registers on the periods when the

equipments are used must be filled.

This analysis may be complemented by

on-site monitoring data, if energy

quantities measurement equipments

are available. In medium or large

buildings, it is advisable to distribute

electricity meters in several building

points for sub-metering and getting

more precise information.

The monitoring data must be analyzed

and reports made and disseminated

among the building users. Information

must be treated considering the target

group. Communication channels must

be chosen depending on the target

group in order to maximize the organi-

zational involvement and energy edu-

cation.

As part of the energy monitoring, the

Energy Manager should also check

frequently the energy contracting

status of the facility, as there must

always be a proper contracted power:

not higher neither smaller than the

power needed. The higher the power

contracted, the bigger the cost will be.

Although the energy contracting does

not provide energy consumption

reductions, it may produce significant

costs savings.

There are several energy suppliers on

a liberalised market. In this context

each user must consult the market on

a regular basis to ask for better energy

supply proposals. In addition, the

energy contracts must be optimized

accordingly to the energy consumption

profile. Especially as regards elec-

tricity, there are usually special tariffs,

e.g. tariffs less expensive during the

night period. Such tariffs should be

chosen and as much as possible of the

electricity consumption should be

moved to night periods. Online

simulators are provided by energy

distributors or regulators that allow

determining the best energy tariff.

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3. ENERGY EFFICIENCY

IN BUILDINGS

The term energy efficiency is in

common use qualitatively, but is

difficult to define or even to

conceptualise. Two concepts of energy

efficiency are put out, a technical

concept and a more broad, subjective

one. An engineer may define energy

efficiency in a restrictive equipment

sense, whereas an environmentalist

may have a more broad view of energy

efficiency. An economist, politician,

sociologist, etc. may each have a

different concept of energy efficiency.

Often energy efficiency has been used

to describe what actually may be

conservation. People with a social view

of energy efficiency might consider the

energy saving to be an efficiency gain,

while those with a more technical view

of efficiency would classify the savings

as conservation rather than efficiency

improvement. For example, consider

an office building that post signs: “Be

more efficient – Use the stairs instead

of the elevator!” If people heed the

sign and take the stairs instead of the

elevators, is this an increase in energy

efficiency? Less energy is used, but

services are reduced.

Another example: A household

undertakes measures such as adding

storm doors, high-efficiency light bulbs

and attic insulations. At the same

time, in the winter the household

raises the thermostat and leaves the

lights on for longer periods, using the

same amount of energy it used

previous. Has this household improved

its energy-use efficiency? In a very

technical sense, the answer is “yes”.

The household receives higher levels

of services (warmer interior) for the

same energy input, and the individual

services are being performed with less

energy intensity (fewer Watts / lumen,

fewer Watts per degree temperature

rise). According to an outcome-based

concept, however, energy efficiency is

not affected unless the higher

temperatures and longer lighting hours

meet additional household needs.

In concluding, when trying to provide a

definition for Energy Efficiency, the

following could be said about it:

a. Increases in energy efficiency take

place when either energy inputs are

reduced for a given level of services

or there are increased or enhanced

services for a given amount of

energy inputs.

b. Energy efficiency (in a more

subjective sense) is the relative

thrift or extravagance with which

energy inputs are used to provide

goods or services.

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Energy services encompass a myriad

of activities, such as powering a

vehicle or a toaster, firing a boiler,

cooling an office, or lighting a parking

lot. To be energy efficient per se is to

provide services with an energy input

that is small relative to a fixed

standard or normal input.

3.1 Energy-using products

Energy-using products, such as elec-

trical and electronic devices or heating

equipment, account for a large

proportion of the consumption of

natural resources and energy, having

also significant environmental impacts.

In this context, the EU has published

Directive 2005/32/EC for setting eco-

design requirements for Energy-using

Products.

Eco-design is a preventive approach,

designed to optimize the

environmental performance of pro-

ducts, while maintaining their

functional qualities. The Directive does

not introduce directly binding

requirements for specific products, but

does define conditions and criteria for

setting, through subsequent

implementing measures, requirements

regarding environmentally relevant

product characteristics and allows

them to be improved quickly and

efficiently. In particular, this Directive

promotes the products’ energy effi-

ciency improvement.

Energy-using products and, in particu-

lar, household appliances (the so-

called white appliances) already have

the indication by labelling and stan-

dard product information of the energy

consumption. This was promoted by

Directive 92/75/EEC. Energy labels

aim at informing and convincing

purchasers to make a greener and

more energy efficient decision in what

concerns household appliances. Energy

labels provide information on the

economic impact of investment

decision by showing that higher initial

costs are paid back by lower energy

costs throughout the lifetime of the

appliance.

When buying new equipments it is

advisable to choose more efficient,

rather than less efficient ones. They

perform best and spend less energy.

The replacement of old equipments by

new and more efficient ones is also

advisable, but in this case a techno-

economic analysis may be provided to

properly evaluate this investment.

Energy efficiency in the EU is rated in

energy levels ranging from A++ (the

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most energy efficient) to G (less

efficient). Apart from a colour-coded

classification there is also other infor-

mation on the energy label such as the

energy consumption, the water con-

sumption or the noise production. A

similar labelling is foreseen for the

whole building, according to the

Directive on Energy Performance of

Buildings (EPBD - 2003/30/EC).

In public institutions the Green Procu-

rement Directives (2004/17/EC and

2004/18/EC), in addition to the energy

efficiency labels, are also valid. These

Directives include environmental

considerations in the selection, award

criteria and contract performance

clauses for public procurement. The

following table shows other energy

efficiency and environmental labels

that are also in use both in the EU and

worldwide.

LABEL AIM PRODUCTS WEBSITE

Energy Star

Provides guidance for selecting energy efficient office equipment.

Buildings sector, residential heating and cooling equipment, major appliances, office equipment, lighting to consumer electronics; office equipment.

www.energystar.gov www.eu-energystar.org

Eco-label

The label is awarded only to those products with the lowest environmental impact in a product range.

Bedding, Soil improvers; Electronic Equipment: Footwear Shoes; Household Appliances, etc.

www.eco-label.com

GEEA-Label

Information about energy-efficient appliances. Uiform voluntary European-wide scheme for energy efficient appliances.

Home electronics, office equipment and IT-equipment with high energy-efficiency profiles

www.efficient-appliances.org

TCO

Quality and environmental labelling system for electronic office equipment.

IT equipment; computers, displays, printers, keyboards and system units; office furniture; mobile phones.

www.tco.se/TCO www.tcodevelopment.com

Also a number of web-tools have been

created to help consumers to choose

more energy efficient appliances, such

as Topten (www.topten.info). This is a

consumer-oriented online search tool,

which presents the best appliances in

various categories of products.

A very important aspect of energy-

using products, especially of the

electronic equipments, is that they

keep on using electricity even when

they are in stand-by mode or off

power due to certain electrical devices

that they possess. At any house, a lot

of Watt-hours per year may be spent

due to stand-by or off power. The

producers are improving the equip-

ments trying to reduce this con-

sumption, so when buying new

equipments their technical

characteristics must be analyzed in

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order to choose those that have small

stand-by power consumptions (typical

values, together with the consumption

of the devices when they are ON, are

shown in the Table of Annex 1).

3.2 Energy Conservation

Measures

In the following paragraphs some

Energy Conservation Measures (ECM)

commonly recommended for service

and domestic buildings are presented.

3.2.1 Building envelope

The building envelope, also known as

the building fabric, comprises the roof,

walls, floors, windows and doors of a

building. Even a properly constructed

and well maintained building will loose

heat from all these components of the

envelope, to a percentage that may

reach 10-15% of its total fuel bill, as

shown in the figure.

Some of the commonly recommended

ECMs to improve the thermal perfor-

mance of the building’s envelope are:

• Insulating the roof reduces the

need for heating in winter and

cooling in summer, and makes the

building a more comfortable place

to be. Radiant heat from an

uninsulated roof makes the

occupants feel uncomfortable, and

they will run the air-conditioner at a

lower temperature to counteract

this problem. If the building is not

insulated at all, roof insulation is

generally more cost effective than

floor or wall insulation.

• Many buildings are built on an

uninsulated, suspended slab. In

cooler climates this will probably

cause occupants to suffer from cold

feet. Insulating the slab will

improve occupant comfort, but is

generally less cost-effective than

insulating the roof.

• Insulating the walls will also

reduce the need for heating and

cooling in your building. The cost

effectiveness of insulating the walls

depends on the external wall area,

the wall-to-window ratio, and the

kind of insulation chosen. Generally,

wall insulation is less cost effective

than roof or floor insulation.

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• Increase window shading: Both

internal and external blinds and

shutters are available as shading

options. Internal shades are less

effective at keeping heat out of a

building than external shades.

Internal blinds give occupants some

control over the light and

temperature of their environment.

On the east and west sides, vertical

shutters may be more effective than

horizontal shutters, which are most

effective on the north and south.

• Increase glazing insulation: The

air layer trapped between the

sheets of glass acts as insulation.

Thus, an extra layer of glazing

decrease heating needs when it is

cold outside and cooling needs

when the weather is warm. Retrofit

of glazing is however expensive,

and may not be cost effective as an

energy conservation measure.

• Increase frame insulation: Heat

can be transferred into (or out of) a

building through the window frame

itself. Thermally broken aluminium

frames contain an insulating layer

between the inside and outside

layers of aluminium, and conduct

less heat than standard aluminium

frames. Wood is less conductive

than aluminium. Although window

replacement is expensive, it is

important to consider the frame

material when installing new

windows or selecting new premises.

• Install a reflective light shelf:

This is a horizontal shelf about two-

thirds of the way up the window.

The shelf serves the double purpose

of shading occupants close to the

windows from glare and distributing

daylight to occupants seated a long

way from windows. Light is

reflected from the shelf, onto the

ceiling and deep into the office.

Installing a light shelf involves

expensive modification of the fabric,

and produces significant savings

only if there are automatic daylight

controls for artificial lighting.

• Change the roof colour: Darker

colour roofs will absorb more heat

from the sun, while lighter colour

roofs will reflect more light, leaving

the building cooler. Keeping heat

out is particularly important for

office buildings.

• Change the wall colour: Light

coloured external walls will reflect

more sunlight than dark coloured

walls, and may reduce the heat

absorbed into the building. Lighter

internal walls will also brighten the

work areas with reflected light.

3.2.2 Heating and Cooling

Although a building may be heated

and/or cooled to a comfortable level, it

does not mean that it is efficiently

heated and/or cooled. Several types of

Heating, Ventilating and Air-

18

conditioning (HVAC) systems may be

used in buildings. Boilers, packaged

heating units, individual space heaters,

furnaces, or district heating systems

are just some examples of the heating

part of HVAC systems. Accordingly, a

large number of measures can be

considered to improve the energy

performance of both primary and

secondary HVAC systems, and some of

them are listed below.

System Airflow

• Grilles may be located or adjusted

such that the effective distribution

of air throughout the occupied

space is not achieved. It may be

simple to re-adjust or relocate a

supply grille to improve this.

• Remove blockages from airflow:

Partial or full blockages can develop

within an air duct, due to dirt and

dust accumulation or obstruction by

a solid object (sometimes occupants

mount cardboard or rags in such a

way as to alter the air distribution

to their own tastes). This result is a

system which does not operate as it

should, with a possible reduction in

energy efficiency.

• Flter cleaning: Air filters are used

to remove particles of dust and

pollutants entering the building or

being spread throughout the

building. These must be cleaned

regularly or excess particles trapped

in the air filter will reduce airflows

and cause poor fan efficiencies.

System use

• Install optimised controls, which

will turn on and off the HVAC such

that the building will operate at set-

point temperature whilst the

building is occupied. The control

system records the outside and

inside air temperatures and

determines how long the building

will take to heat up or cool down,

switching the air conditioning on

and off at the appropriate times.

• Reduce scheduled hours of

operation: This is simply to reset

the time-clock so as to restrict the

hours of operation of the HVAC

system. If the temperature rises or

falls slightly at the end of the

occupancy period is not a problem,

and the energy advantage of such a

small adjustment, particularly in

peak seasons, could be significant.

• Reduce effects of out-of-hours

use: By reducing the heating and

increasing the cooling set-point

temperatures for out-of-hours

operation, the HVAC system energy

use will be considerably reduced.

• Reduce area serviced for out-of-

hours demand: Out-of-hours

operation of the HVAC system may

only be required for a small part of

the building. It may thus be

19

possible to isolate part of the

system to be alone served during

out-of-hours operation.

Chiller plant

• Significant energy savings may be

available from the replacement of

the existing chiller with a more

appropriate or updated unit.

• Improved match to load profile:

Different types of chillers operate

more efficiently at different loads,

thus the load profile of the

installation should be matched to

the most appropriate chiller type to

optimise energy efficiency.

• Correct adjustment of the chiller

controls sequencing is important

to the efficient operation of the

system, especially where there are

more than one chillers.

• Cooling tower fans can be

variable speed controlled to reduce

power consumption.

• Condenser water can be used for

heat reclaim for the heating of DHW

or space heating.

• Chiller compressor: Depending on

the size and type of installation will

determine the most efficient type of

compressor to be used.

• Replace cooling towers: Existing

cooling towers may be inefficient in

their operation, allowing energy

savings to be made by replacing

them with new units.

• The chilled water control system

and condenser water set-points

can be adjusted to better suit the

load demand, thereby achieving

improved energy efficiencies.

Boiler plant

• Significant energy savings may be

available from the replacement of

the existing boiler with a more

appropriate or updated type.

• Improved match to load profile:

Energy efficiency can be optimised

by matching the size and number of

boilers operating at a given load.

• Minor adjustments to boilers’

settings and calibrations can

improve efficiency.

• Correct adjustment of boilers’

sequencing controls, according to

the variations in the heating load,

will be important to the efficient

operation of the heating system.

• Adjust hot water set points: The

heating control system set-points

can be adjusted to better suit the

load demand, thereby achieving

higher overall energy efficiencies.

• Stack sensor control: Automatic

boiler controls are able to vary the

forced draught fan speed according

to the excess air sensed in the

boiler flue. This achieves improved

boiler efficiency.

Chilled and hot water circulation

• Decentralise chilled/hot water

production: Centralised chiller and

boiler installations may include

extensive pipework giving rise to

high pipe losses. Greater energy

efficiency may be achieved using a

number of smaller chillers/ boilers

located nearer to the loads.

• Centralise chilled water and/or

heating production: Where there

are a number of smaller chillers/

20

boilers which are relatively close,

and depending on the load profile,

energy savings are possible using a

single centralised chiller unit or

boiler. Reductions in maintenance

costs will also be achieved.

• Variable speed motor drives: The

use of variable speed motor drives

for chilled/hot water circulation

pump sets can greatly improve the

energy efficiency of the installation.

• Reduced circulation volume: It is

possible that a greater amount of

chilled/hot water than is necessary

is being circulated around the

building to meet the peak load.

Rebalancing of the system will

enable the flow rate to be reduced.

• By reducing the pump capacity

to suit the load energy saving and

greater pump life can be achieved.

• Modulation of circulation

temperatures to match demand:

It may be possible a reduction in

operating temperatures, with

consequent savings in heat lost

from the distribution pipework.

• Reduce hours of circulation:

Many systems operate longer than

required. By reducing the operating

hours of the pump the energy

consumption will be also reduced.

• Improve pipe insulation: If the

pipe insulation is in bad state of

repair or is not of sufficient

thickness, it will be beneficial to

replace the insulation with new,

reducing the energy wasted.

• Improve valve insulation: The

insulation around valves breaks

down over time. By replacing it with

a more flexible type the losses from

the valves will be reduced.

• Reduce pipe length: Pump

capacity as well as pipework energy

losses are associated with the

length of pipe run. It may be

possible to redirect pipework such

that lengths are reduced.

Plant general

• Replace pump/pump motor/

drive: Equipment which is close to

the end of its serviceable lifespan is

unlikely to operate efficiently. By

replacing the equipment overall

efficiencies will be greater, and

energy savings and maintenance

cost reductions will be made.

• Matching to load: When installing

any plant item it is important that it

is sized to match the demand. By

reducing the equipment capacity to

match the load, unit efficiency will

be improved allowing savings and

greater equipment lifespan.

• Install economy cycle: An

economy cycle allows air to be

recirculated during periods when

fresh air is not required. The result

will be reductions in unnecessary

heating or cooling of outdoor air

and consequent energy savings.

21

• Where air cannot be re-circulated,

air-air heat recovery equipment

will allow the transfer of heat

between intake and discharge air-

streams. The result will be reduction

in unnecessary heating/cooling and

consequent energy savings.

• Install chiller heat recovery: This

uses heat normally rejected to

atmosphere from the chiller to

preheat water for space heating or

domestic hot water. The overall

result is a saving in energy.

3.2.3 Domestic Hot Water

The domestic hot water (DHW) may be

produced using boilers, RES systems

or district heating. Choosing between

them depends on the energy resources

availability, demand requirements,

safety, and economical considerations.

There are four basic ways to cut the

water heating bills: use less hot water,

turn down the thermostat on the water

heater, insulate the water heater, or

buy a new, more efficient model.

Simple measures that can help provide

hot water using less energy are:

• Reduce storage temperature: If

the hot water storage temperature

is higher than necessary decreasing

this temperature will also decrease

the heat loss and energy wasted.

The temperature cannot be reduced

below 60oC however, as below this

limit it is possible that Legionella

bacteria (causing the Legionnaires'

disease) are going to be developed.

• Reduce DHW circulation

temperature: If the hot water

distribution temperature is higher

than necessary, decreasing the

distribution temperature will also

decrease the heat loss from

distribution pipework. The

distribution temperature should not

be below 55oC however.

• Reduce tap flows: By installing a

flow restrictor device upstream from

the tap, the hot water use can be

significantly reduced, without

affecting the user.

• Reduce shower flows: By

installing a flow restrictor device

upstream of the shower rose, or by

replacing the shower rose itself, hot

water use can be significantly

reduced, without affecting the user.

• Decentralise DHW production:

Centralised hot water generation

installations may include extensive

pipework reticulation giving rise to

high pipework heat losses. Greater

energy efficiency may be achieved

using a number of smaller hot water

generation units located nearer to

the hot water points of use.

• Centralise DHW production:

Where there are a number of

smaller hot water generation units

which are relatively close, and

depending upon the hot water load

22

profile, it is possible that greater

energy efficiency is possible using

centralised hot water generation.

� Coordination of DHW/Service

hot water production: Hot water

may be used for a number of

purposes within a building. By co-

ordinating the use of hot water for

different purposes and at different

times it may be possible to reduce

the hot water storage requirements

or the maximum simultaneous

demand. This could result in a

reduction in the DHW generation

plant sizing, with a consequent

reduction in overall energy cost.

3.2.4 Lighting

Lighting the buildings needs energy

and money, not only due to the

electricity consumption, but also due

to the maintenance of the lighting

system. Energy savings may result

from the combination between diffe-

rent types of lamps with their specific

supporting hardware (such as

luminaires and ballasts) and the way

the lighting systems are applied in

everyday use. The lighting efficiency

can be improved by taking the

measures presented in the following.

Lighting Design

• The reflective surfaces of luminaires

must be kept clean. Cleaning the

luminaires will not save energy in

itself, but with cleaner luminaires a

better level of lighting for the same

energy use can be maintained.

• Replacement of lamps with

higher efficiency units: Standard

mono-phosphor 26mm fluorescent

tubes are 10% more efficient than

their 38mm predecessors. CFLs are

about 4 times more efficient than

equivalent incandescent lamps.

• Where light levels exceed Standards

or are poorly matched to user needs

(see Annex 2), it is possible to save

energy by removing unnecessary

lamps and labelling de-lamped

holders accordingly.

• Selective replacement of tubes,

i.e. replacement of lower light

output monophosphor fluorescent

tubes with higher light output

triphosphor fluorescent tubes. The

energy savings from this measure

arise through the “selective”

component, as fewer tubes are

required to meet the same overall

lighting levels.

• Installation of autotransformers

provides an alternative method for

reducing the energy use and light

output of an installation. Auto-

ransformers work by steeping back

the voltage in the lighting circuits,

thereby decreasing light output and

energy use.

23

• The replacement of diffusers can

improve efficiency if accompanied

by de-tubing.

• Reducing the number of

luminaires can reduce overlighting

problems, this way improving

occupant comfort and energy

efficiency. Relocating luminaires

relative to occupant work areas can

reduce the number of luminaires

required, reduce glare problems,

and improve light levels.

• The replacement of ballasts in

fluorescent luminaires can achieve

some energy savings.

• It is more cost effective in some

cases to refurbish old luminaires

than replace them. Replacement

can be more cost effective

depending on the type of luminaire

being replaced.

Lighting Control

• Improved switching of lights by

occupants: The most effective way

of insuring that lights are switched

off is to assign to one person in

each work area the responsibility for

checking that lights are switched off

at the end of day.

• Improved switching of lights by

cleaners and security staff:

Cleaners are known for a tendency

to light up the whole building and

then turn off lights progressively as

they clean each area. They have to

light up the building on a floor-by-

floor basis only.

• Improved zoning of switching

1. Matching use patterns: Having

just one switch to control the

lights on a whole floor is very

inefficient, especially in hours

when one or two people might be

in the building. Matching the

switching arrangements to

individual use zones in the

building is much more efficient.

2. Matching daylight availability:

Matching the switching groups to

daylight availability means that

the lights that aren't needed

during daylight hours can be

turned off, while leaving the

lights on in parts of the building

that aren't naturally lit.

3. Improving accessibility: Moving

and labelling the switches to

make them more accessible will

ultimately lead to energy savings.

• Improved maintenance of

controls: Automating lighting

controls are only useful while they

are working well. Experience shows

that the probability of occupant

interference with automatic lighting

controls is also quite high. It is

important to regularly check such

controls and ensure that they are

working effectively.

• Automated occupancy control

systems use movement sensors to

determine whether to switch the

lights on. Introducing automated

occupancy control can sometimes

lead to energy savings through

reduced hours of operation. Care is

required to ensure that the controls

work for, rather than against, the

occupants ' needs.

24

• Daylight controls can conserve

energy by reducing the hours of

lighting operation. Automated

control systems contain light

sensors that shut down some or all

of the lights in an area when the

light levels are high enough. If

lights are fitted with dimmable

electronic ballasts, the lights can

also be dimmed according to the

ambient conditions. It is preferable

to use a continuously variable

system rather than a switching

system for adjusting light levels, as

occupants tend to be irritated by

lights turning on and off.

3.2.5 Domestic appliances

Laundry machines use electricity in

drum rotation, for water circulation,

heating and removal, and air heating.

Useful strategies to improve energy

efficiency when doing laundry include:

� put the laundry machines in good

ventilated places;

� adjust the washing clothes volume

to the equipment capacity;

� regularly cleaning of filters and

detergent distributors;

� separate clothes accordingly to their

colour, materials and dirty; use of

low temperatures programs and eco

options for less dirty clothes;

� choose laundry machines that have

a clothe weighting function that

automatically adjust the amount of

water needed;

� avoid pre-washing programs;

� use the centrifugation option in

washing machines instead of using

the drying machine;

� drying of the clothes, as much as

possible, in the outdoors;

� when using a drying machine,

separate light tissues from more

dense clothes and not mix partially

dry clothes with wet ones;

� if the drying machine has a vapour

escaping tube, keep it as short as

possible to increasing its efficiency;

� if the drying machine has a clothing

humidity controller, use it to auto-

matically disconnect the equipment

when the clothes are dry.

In the case of dishwashers the main

electricity consumption is due to water

and air heating. The energy efficiency

of dishwashers can be improved by:

� adjusting the amount of dishes to

the equipment’s capacity;

� regularly cleaning of filters;

� removing the excess of food using

used paper napkins or water;

25

� choosing shorter washing programs

and the eco option for water and

energy savings.

Refrigerators and freezers use elec-

tricity to produce cold. A few simple

measures can help make significant

energy savings:

� These equipments take heat from

inside the system and release it

outside. The warmer the air around

the equipment, the less efficient it

will be. Therefore, their correct

placement makes a huge

difference to their efficiency.

� Check the equipments in order to

verify that they are not refrigerating

below the recommended tempe-

ratures: increasing the temperature

of the cooled space by just 1ºC

could reduce energy consumption

by 2% (recommended temperatures

of operation for refrigerators: 3ºC

to 5ºC, and for freezers: -15ºC).

� Make sure that doors are not left

open for longer periods than neces-

sary: complete loading and

unloading as quickly as possible.

� Consider cooling rather than refri-

geration: some products will stay

fresh with very slight cooling rather

than active refrigeration.

� Monitor the control settings

periodically to ensure they remain

at optimum levels.

� Keep external condensers clean and

free from blockages.

� De-ice the evaporators regularly.

� Assure a proper insulation by

replacing insulators when needed.

� The manufacturers’ instructions for

maintenance should be followed.

� Keep the food in closed spaces: the

water exchange between food and

the air consumes energy.

� Avoid introducing food hotter than

35-40ºC (it is recommended to cool

it first outside and unfreezing it in

the refrigerator in order to release

cold there).

� Switch off refrigerators when they

are not needed, especially in

holiday periods.

� Not filling in excess the refrigerators

allowing the air circulation.

� The food must be grouped accordin-

gly to its cold needs (the coldest

place in the refrigerator is its lower

area).

Ovens and cookers use energy to

produce heat to cook food. The heat

may be generated by electrical

resistances, by gas combustion or by

radiation (microwaves). Some tips that

can help make energy savings are:

� when cooking, pre-heat the oven in

less time than the recommended;

� use the light and a timer to control

cooking, avoiding to open the oven;

� promote a better heat circulation

and a faster cooking trough the use

of the fan;

� turn off the oven 15 minutes before

finishing the cooking: it will use the

remaining heat;

26

� use glass or ceramic pots since they

retain more heat;

� use the microwave as much as

possible;

� clean the oven and the cookers in a

regular basis.

In any case, and as concerns any type

of household appliance, it is important

to choose the equipments considering

their energy efficiency (i.e. those with

the best energy label classification).

Currently the market offers innu-

merable household appliances options,

with excellent energy efficiency perfor-

mances (see Chapter 3.1). In addition,

the proper capacity for the needs

should be chosen each time.

3.2.6 Office equipment

In the office equipment, the following

items are generally included: compu-

ters, monitors, fax machines, photoco-

piers, printers, telephones, mobile

phones, modems, etc. Although long

term energy cost savings in this field

can be made by purchasing energy

efficient equipment, some relevant

energy saving tips are:

• Turn off equipment at night:

Turning off the office equipment at

night is a simple measure which can

make significant energy savings.

PCs, for example, use 100-150 W of

power, and office buildings and

schools have hundreds of them

inside. Assign individuals with the

responsibility for turning off

equipment, and run a sustained

switch-off campaign.

• Turn off equipment when not in

use: Encourage staff to switch off

equipment at their workstations

before leaving for lunch or

meetings. If long warm-up times on

photocopiers or faxes are annoying,

use the ‘stand-by’ button. If you

don’t want to wait for computers to

boot-up, just turning off the screen

can reduce the energy consumption

by more than half.

• Activate Energy Star features:

Most modern office equipment has

energy saving features built in

under the Energy Star program, but

normally these features need to be

activated.

3.2.7 Renewable Energy

Systems

There are many options for using

renewable energies at buildings, from

solar-powered outdoor lights to buying

renewable energy from the local utility

to even producing electricity e.g. at

home with photovoltaic (PV) cells.

Renewable Energy tips

27

• A new building provides the best

opportunity for designing and

orienting it to take advantage of the

sun’s rays. A well-oriented building

admits low-angle winter sun to

reduce heating bills and rejects

overhead summer sun to reduce

cooling bills.

• Many consumers all over the EU buy

electricity produced from RES like

the sun, wind, water, biomass, and

the Earth’s internal heat. This power

is sometimes called “green power”.

Buing green power from theutility is

one of the easiest ways to use

renewable energy without having to

invest in equipment or take an

extra maintenance.

• A main use of solar energy is for

heating water. Solar water heating

systems are environmental friendly

(during a 20-year period, one solar

water heater can avoid more than

50 tons of CO2 emissions), and can

now be installed on any roof to

blend with the architecture of the

building. In addition, if there is a

swimming pool or hot tub, solar

energy can be used to cut the pool’s

heating costs. Most solar pool

heating systems are cost

competitive with conventional ones.

Long-term saving tips

• If the building was made as energy

efficient as possible and very high

electricity bills occur while there is a

good solar resource in the site, then

it might be worthy to consider the

possibility of generating own

electricity using PV cells. New

products are available that integrate

PV cells with the roof, making them

much less visible than older

systems. However, more research is

needed if a decision to invest in a

PV system is made.

• There are other systems that exploit

the local RES potential, such as

biomass systems for heating

buildings (burning logwoods, chips

or pellets), ground source heat

pumps, which are used for both

heating the building in winter and

cooling it during summer, etc. The

decision on whether to proceed with

such an installation or not should be

based on proper feasibility analysis.

3.3 Energy Saving

Behaviours

In trying to create the most Earth-

friendly, energy-efficient buildings

possible, architects and engineers

have stumbled on a problem they

hadn't fully understood: the occupants

-users of the buildings. Indeed,

designers have found ways to make

cooling and heating systems more

efficient than ever, mainly by using

cutting-edge technology and old-

school techniques, such as natural

ventilation. But the challenges

associated with changing the

28

occupants’ behaviour form another,

and in many respects more

challenging, part of the problem

As energy consumers, people do not

simply consume gas or electricity, but

rather the services that these energy

sources provide. Most of the times,

energy use at home, school, office... is

invisible and the energy consuming

behaviours are based on routine and

habit. The desktop computer remains

on even when we are out to lunch, we

turn the lights on and leave them even

if we are not in the room, we leave

televisions on standby, etc. without

having to think about how these

actions are carried out, where the

energy comes from or what the

environmental consequences are.

These behaviours are both complicated

and difficult to change, partly because

they are shaped by the characteristics

of the building and the energy-using

appliances, but more importantly

because they are influenced by a

range of internal and external factors,

such as our beliefs, values and

attitudes, other people’s behaviours,

the cultural settings we live in, and

various economic incentives and

constraints. Behaviour can, however,

be influenced and in some cases it has

changed rather rapidly, for example in

the increased popularity of organic

food. Changing buildings occupants’

energy consuming behaviours was

proved to be more complicated.

In the context of sustainable energy,

‘behaviour change’ can be broken

down into two broad categories:

• changes to purchasing behaviour,

and

• changes to routine behaviour.

The most common use of the term

‘behaviour change’ refers to changes in

routine behaviour – in other words,

someone actually changing what

he/she does on a day to day basis.

However, in the case of sustainable

energy, purchasing behaviour is also

important, as discussed below.

Changes to purchasing behaviour

• Purchase the low carbon option:

Such purchases are generally

prompted by the need for

replacement, for example when a

washing machine breaks down, or a

light bulb needs to be replaced. By

their nature they are relatively rare

purchases, and require only a

modification in behaviour (i.e. a

change in purchase decision in

favour of the most energy efficient

replacement).

• Make a new sort of purchase:

Such purchases are not prompted

by the need for replacement, for

example buying loft or cavity wall

insulation, or installing micro-

generation. They are essentially

new behaviours, and require

consumers to do something they

29

weren’t necessarily going to do in

the first place.

Changes to routine behaviour

• Minor change to a common

routine: Some changes to existing

routines are relatively simple and

easy to implement, for example

switching off the lights and turning

appliances off standby.

• Behave in a completely new

way: Other changes to existing

routines require a complete change

in behaviour, for example using a

ceiling fan instead of an air-

conditioner, woods for cooking, etc.

Several studies have looked at the

impact of intervention measures such

as various forms of feedback on

energy consumption, the use of better

and more informative bills, or financial

rewards and incentives, as well as

employing techniques such as

community-based campaigns or the

use of micro-generation technologies.

Some of these interventions appear to

have resulted in considerable energy

savings. For example, studies on

feedback on energy use show an

average of 5%-15% energy savings in

the short-term, while studies of

community-based Eco-teams (where

people get together on a monthly basis

to discuss their energy, waste,

transport and water use) suggest that

even larger savings are possible.

More fundamental changes in buildings

occupants’ behaviour is likely to

require a holistic approach, that goes

beyond energy use in the home/school

/office to also consider transport,

waste and water use – all of which

ultimately have energy and climate

impacts. Nevertheless, the most

important strategy for shaping energy

related consumer behaviour is

education. It is crucial to provide all

building users proper information and

education on energy conscious

behaviours and energy efficiency in

order to achieve effective energy

savings, and this has to start even

from the school age.

30

4. ENERGY AUDIT

An energy audit is the general term

used for a systematic procedure that

aims at obtaining an adequate

knowledge of the energy consumption

profile of a building or an industrial

plant. It also aims at identifying and

scaling the cost-effective energy

saving opportunities for the unit.

Energy audits are crucial in the

implementation of energy saving

measures and in the assurance of the

targets of Energy Management.

In an energy audit:

• the main goal is to achieve energy

savings,

• there may be other aspects to

consider (technical condition,

environment) but the main interest

is on energy consumption and

saving possibilities,

• reports on energy saving measures

are produced,

• the work may cover all energy

using aspects of a site or certain

limited parts (systems, equipment)

of several sites (horizontal audit).

The term “energy audit” may have

different meaning depending on the

country and the service provider.

There may be another name for the

whole process (such as energy survey,

assessment, etc.), but the activity

meets the same criteria that stand for

an energy audit. It is also important to

notice that energy audit is not a

continuous activity but should be

repeated periodically.

4.1 Types of Energy Audits

Energy auditing of buildings can range

from a short walk-through of the

facility to a very detailed analysis with

hourly computer simulation. Generally,

four types of energy audits can be

distinguished and are briefly described

in the following.

4.1.1 Walk-through Audit

This audit consists of a short on-site

visit of the facility to identify areas

where simple and inexpensive actions

can provide immediate energy use

and/or operating cost savings. Some

engineers refer to these types of

actions as operating and maintenance

(O&M) measures (e.g. setting back

heating set point temperatures,

replacing broken windows, insulating

exposed hot water or steam pipes, and

adjusting the boiler’s fuel-air ratio).

4.1.2 Utility Cost Analysis

The main purpose of this type of audit

is to carefully analyze the operating

costs of the facility. Typically, the

utility data over several years are

31

evaluated to identify the patterns of

energy use, peak demand, weather

effects, and potential for energy

savings. To perform this analysis, it is

recommended that the energy auditor

conduct a walk-through survey to get

acquainted with the facility and its

energy systems.

It is important that the energy auditor

understands clearly the utility rate

structure that applies to the facility for

several reasons including:

• To check the utility charges and

insure that no mistakes were made

in calculating the monthly bills. The

utility rate structures for

commercial and industrial facilities

can be quite complex with ratchet

charges and power factor penalties.

• To determine the most dominant

charges in the utility bills. For

instance, peak demand charges can

be significant portion of the utility

bill especially when ratchet rates

are applied. Peak shaving measures

can be then recommended to

reduce these demand charges.

• To identify if the facility can benefit

from using other utility rate

structures to purchase cheaper fuel

and reduce its operating costs. This

analysis can provide a significant

reduction in the utility bills,

specially with the electrical

deregulation and the advent of real

time pricing rate structures.

Moreover, the energy auditor can

determine whether or not the facility is

valid for energy retrofit projects by

analyzing the utility data. Indeed, the

energy use of the facility can be

normalized and compared to indices

(for instance, the energy use per unit

of floor area - for buildings).

4.1.3 Standard Energy Audit

The “standard audit” provides a

comprehensive energy analysis of the

energy systems of the facility. In

addition to the activities described for

the walk-through audit and the utility

cost analysis described above, the

standard energy audit includes the

development of a baseline for the

energy use of the facility and the

evaluation of the energy savings and

the cost effectiveness of appropriately

selected energy saving measures. The

step-by-step approach of the standard

energy audit is similar to that of the

detailed energy audit that is described

later on in the following section.

Typically, simplified tools are used to

develop baseline energy models and to

predict the energy savings of energy

conservation measures. Among these

tools are the degree-day methods, and

linear regression models. In addition, a

simple payback analysis is generally

performed to determine the cost-

effectiveness of energy conservation

measures.

4.1.4 Detailed Energy Audit

This audit is the most comprehensive

but also time-consuming energy audit

type. Specifically, the detailed (else

“diagnostic”) energy audit includes the

use of instruments to measure energy

use for the whole building and/or for

some energy systems within the

building (for instance by end-uses:

32

lighting, office equipment, fans, chiller,

etc.). In addition, sophisticated

computer simulation programs are

used in detailed energy audits to

evaluate and recommend energy

retrofits for the facility, but they

require high level of engineering

expertise and training.

In the detailed energy audit, more

rigorous economical evaluation of the

energy conservation measures is

generally performed. Specifically, the

cost-effectiveness of energy retrofits

may be determined based on the life-

cycle cost (LCC) analysis rather than

the simple payback period analysis.

LCC analysis takes into account a

number of economic parameters such

as interest, inflation, and tax rates.

4.2 Energy Surveys

Energy surveys are an integral part of

the auditing process and they aim to

evaluate the energy flows within

facilities, to identify energy wastage

and to make recommendations on the

future energy management of the

facility. Energy surveys, with the

exception of specifically targeted

surveys, cover all aspects relating to a

facility’s energy consumption.

This will involve detailed surveys of:

� the management and operation

characteristics of a facility or orga-

nization: who is responsible for

energy and effective energy con-

sumption; the use of a particular

space or building; the mechanical

and electrical services; the number

and type of occupants, and the

occupancy patterns of buildings

and spaces; the indoor conditions

within spaces and buildings (air

temperature, relative humidity,

luminance levels, etc); and the

operating practices of major items

of plant and equipment (description

of the field, type of technologies,

procedures and services used,

available technical documentation

(heating technology, building …);

� the energy supply to an organiza-

tion’s various facilities: list of types

of energy sources and their origin;

� the energy use within a facility: list

of the biggest heat and power

consumers; consumption quantifi-

cation; planned and finished

projects in the field of effective

energy consumption and environ-

mental protection;

� the plant and equipment within a

facility;

� the fabrication type of buildings.

The management culture within an

organization can have a great influen-

ce on energy consumption. It is there-

fore important to determine the mana-

gement structure and practices

relating to energy procurement and

consumption. Maintenance practices

can also have a direct influence on

energy consumption, so it is important

33

to establish the frequency and quality

of the maintenance procedures, and to

identify new maintenance measures

which could improve the energy

performance of plant and equipments.

It is also important to identify the

tariffs and supply contracts under

which the organization purchases its

energy. This will allow determining

whether or not the organization is

purchasing energy at the lowest price.

Other important aspects to be

surveyed during this phase include the

analysis of pre-existing energy audit

reports, the use of renewable energy

sources, the building’s user’s opinion

on the building energy and comfort

conditions, and the energy consuming

equipments inventory.

4.3 Data collection on the

Energy Use

The accuracy of an energy audit

depends on the collection and input of

good quality data. In order to ensure

accuracy, proper collection procedures

must be established. If too few data

are used, any analysis will be

meaningless. By contrast, if excessive

data are collected it will difficult the

analysis procedure. In some cases,

data from various sources may be

incompatible, making comparisons

very difficult. In addition, errors may

occur when meters are read incorrectly

and also when readings are incorrectly

logged.

4.3.1 Data from invoices

Data collection from invoices involves

collecting several utility and fuel bills,

extracting their information and intro-

ducing data into a computer. An audit

procedure usually requires a minimum

12 month analysis to an ideal of 36

month analysis. Procedures must be

implemented to assure that the correct

time periods are covered. It is

important to focus the audit dates on

the consumption dates and not to the

billing dates.

The electricity invoices content may

vary depending on the country (e.g.,

in many countries the electricity bill

includes also a tax regarding the public

TV service). In general, the electricity

invoices present data in a monthly

basis and contain the following

information:

(1) the date of the meter reading or

estimation of the consumption;

(2) the present and previous meter

readings, with the number of units

supplied [kWh]; this may be

differentiated accordingly to

several time periods (daytime,

night-time, peak rate, etc);

(3) the charges for each unit of electric

energy consumed; these are

different according to the relevant

time period;

(4) the monthly maximum demand

charge for every kW or kVA of the

peak power demand occurring

during the billing month;

(5) the VAT charged on the bill,

together with the total cost due.

A typical natural gas invoice may

include the following:

(1) the date of the meter reading or

estimation of the consumption,

34

(2) the present and previous meter

readings, with the number of units

supplied [m3],

(3) the unit price per kWh equivalent

of natural gas,

(4) a fixed monthly charge,

(5) the VAT charged on the bill,

together with the total cost due,

(6) the calorific value of gas [J/m3].

Solid and/or liquid fuels invoices

generally state the weight delivered

and the cost. However, especially for

solid fuels, it is necessary to know the

heating value, humidity, ash content,

stable carbon and volatile substances.

These data may be obtained from the

fuel’s supplier.

In many countries, especially in central

and northern Europe, buildings and

towns rely on heat produced in district

heating plants. The heat is usually

supplied in the form of medium-

pressure or high-pressure water from

a district heating plant and transferred

to the individual buildings via heat

exchangers.

The heat energy consumption is

recorded by heat meters, which record

the water flow rate, and the tempera-

tures of the water entering and leaving

the facility, thus determining the

energy consumed. The accuracy of

heat meters is affected by variations in

temperature and flow rate.

4.3.2 Data from meters

Meter reading provides a useful source

of energy data. However, several

problems may occur and reduce the

data accuracy, like reading lost,

meters change, or even meters that do

not read at all. Therefore, meter

readings should be validated and

several checks made. For example, it

should be checked:

� that the correct number of digits is

recorded;

� that current readings are higher

than previous readings;

� that readings are within predicted

energy consumption bands;

� the date of meter readings.

The manual reading of meters and the

writing down of digits by hand is a

time consuming process which enhan-

ces the probability of mistakes. The

smart metering systems provide an

excellent alternative to the manual

approach since they can be connected

to data capture units, but are not

always available.

In situations where existing metering

is unable to provide enough detailed

information on energy consumption, it

may be necessary to install additional

submetering. Although the submeters

provide detailed and precise data, the

installation of these equipments may

be expensive and inconvenient.

35

During an on-site visit, hand-held and

clamp-on instruments can be used to

determine the variation of some

building parameters such as the indoor

air temperature, the luminance level,

and the electrical energy use. When

long-term measurements are needed,

sensors are typically used and

connected to a data-acquisition system

so measured data can be stored and

be remotely accessible. In addition,

non-intrusive load monitoring (NILM)

techniques are also used lately.

4.4 Data Analysis

One of the main aims of an energy

audit is the configuration of energy

baseline regarding the reference

consumption or specific consumption

for individual installations and devices.

With the use of such standards, energy

consumption before and after the

application of energy saving measures

can be estimated. A proper energy

data analysis is important in order to

correctly identify trends and areas of

improvement.

4.4.1 Energy consumption

The simplest analysis that can be

undertaken is to produce a percentage

breakdown of annual energy consump-

tion and cost data. This enables an

easy assessment of the overall energy

performance of a building. It includes:

� energy consumption conversion to

toe using national approved

conversion factors;

� building energy efficiency indicators

calculation [e.g. kWh/m2/year];

� percentage breakdown of the total

consumption and cost of each

energy form, and determination of

the average unit cost per Toe for

each;

� compilation of a table showing the

total annual energy consumption,

cost and percentage breakdown of

each energy type (kWh, kg, etc);

� pie charts elaboration that show

graphically the energy and cost

contributions of each energy type;

� where historical energy data are

available, comparisons should be

made in order to identify trends.

The annual energy consumption may

also be converted, through an

appropriate (country specific)

conversion factor, to carbon intensity

[tonnes CO2/year]. Energy conversion

values for different forms of energy

are presented in Annex 2.

4.4.2 Performance indicators

It is not a simple task to compare the

energy use of two buildings. Indeed,

the size, the location, the function can

be significant factors in a building’s

energy use. Therefore, energy auditors

typically use ratios to compare energy

consumption of different buildings with

similar attributes. These ratios are

generally calculated based on the

energy utility bills or the data collected

during the site visit. The estimated

ratios can be then compared to

reference ratios established for similar

buildings (same function, location,

etc.) in order to assess of the energy

efficiency of the building.

36

The ratios are typically used for

various reasons including:

� to detect high energy consumption

and to assess if an energy audit will

be beneficial.

� to assess if the target for energy

efficiency has been achieved for the

building. If not, the magnitude of

the required energy use reduction

can be estimated.

� to estimate heating, electricity and

water costs to be expected for new

buildings.

� to monitor the evolution of energy

consumption of audited -or not-

buildings and estimate the

effectiveness and profitability of

work carried out following an audit.

A ratio is an economic or technical

indicator that is calculated as a

fraction (which is made of a numerator

and a denominator). Different types of

numerators and denominators can be

used to define a ratio.

Quantities of energy are typically used

for the numerator:

� The most commonly used value is

the kWh of energy consumed. To

add the different energy supplies, a

reference should be chosen, either

primary energy, expressed in toe,

or final energy (e.g. “useful heat”)

expressed in kWh.

� A monetary value (e.g. Euros) to

visualize energy spending, but this

value may depend on various

economical parameters, such as the

inflation rate of the country.

� Energy demand (in kW).

For energy analysis, the most

frequently used denominators include:

� Units of productions (specially for

manufacturing facilities).

� Surface area or space volume (such

as heating area or volume in office

spaces in m2 or m3).

� Users (in office buildings, schools,

hotels, theatres...).

� Degree-day (with generally 18°C as

a base temperature).

� Theoretical needs, for comparing

them to the actual energy

consumption.

4.4.3 Energy time-charts

Processing all the data during selected

in the first stage of the energy audit of

the building/unit, allows a preliminary

analysis of its energy consuming

behaviour. Thus, during the in-site

survey of the energy systems

characteristics, a picture about their

historical and seasonal energy

consumption behaviour can be

obtained. Using the primary data

selected, it is possible to produce the

energy consumption vs. time charts.

An energy consumption time chart of a

facility (e.g. a building block) is a

graphical representation of the power

contained in a particular energy source

as a function of time, for a specific

time period. It is constructed using the

data logged on the energy meters

(electricity, petrol, gas, etc.). This type

of chart provides the observer with

direct information and allows for a first

estimation about the way and the main

areas of energy use in an hourly, daily,

monthly and also in a seasonal basis.

37

Monthly Electrical Energy Use

0

200

400

600

800

1000

1200

1400

1600

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Month

Ene

rgy

Use

(M

Wh)

-5

0

5

10

15

20

25

30

Mon

thly

Ave

rage

Out

door

T

empe

ratu

re (

°C)

MWh 93 DB 5(°C)

Such time-charts must be constructed

at least for the following cases:

- Electricity consumption time-chart

on an hourly and/or daily basis;

- Fuel consumption time-chart on a

daily basis.

As long as the aim of the auditing

procedure is to locate the peak energy

saving potential of the building/unit, it

is purposeful to construct a time chart

of the typical daily (or monthly) load

coefficient. This coefficient is defined

as the ratio of the electrical peak load

and daily (or monthly) hours product,

to the respective energy consumption.

4.4.4 Energy balances

Energy flow in a building, from its

internal distribution to its final

consumption per use and per energy

system, can be easily understood

when each system is represented with

the aid of a Sankey diagram. In these

diagrams, the energy losses-outflows,

the energy gains-inflows, and the

useful energy in every energy system

are represented quantitatively and in

proportion to the total energy inflow,

according to existing data from energy

bills and invoices, from calculations

and in-site measurements of the unit.

Representing energy flows visually

with the aid of the Sankey diagrams

helps to locate the more critical energy

consuming areas of the building, unit

or building block, and, at the same

time, to identify the sources that lead

to energy losses. This ascertainment

leads to a sound evaluation of each

system’s behaviour, as well as to a

better scheduling of the proposed

energy saving measures.

The Sankey diagram of Figure 4.1

represents the flow of primary energy

used for space and water heating in a

house. Oil is used for water and space

heating, while electricity is used for

the part of the space-heating load not

covered by the oil-fired system. There

is also a heat exchanger system that

recovers heat from the warm airflow.

In the Sankey diagrams of Figure 4.2

the energy flows in an air-conditioned

space, during the cooling and heating

periods respectively, are shown.

38

Figure 4.1: Energy flows in the case of space heating and DHW production in a

domestic building

Figure 4.2: Sankey diagram of energy flows in a conditioned space during heating

and cooling periods

39

4.5 Drawing up of Energy

Saving Plans

The energy audit procedure leads to a

final determination of the energy

savings potential, with the use of

tiding-up measures and simple

inexpensive actions that don’t need

economic payback assessment through

relevant energy studies. Additionally, it

leads to a determination of the energy

saving potential in specific areas and

systems, for further examination in a

following stage, by specialists or by

the buildings’ administration staff,

whenever this is feasible.

These potentially energy saving

actions must be divided into three

groups according to their energy

saving potential for the particular

building (high, medium, low). This

involves identifying and quantifying

energy costs and highlighting those

measures which offer the greatest

potential savings. Other aspects like

the implementation timescale, the

required investment and the payback

period are crucial aspects to support

priority decision.

Energy can often be saved at no

capital expense simply by improving

maintenance procedures and imple-

menting good practices. In fact, many

energy management opportunities

consist of ‘low cost’ or ‘no cost’

measures such as:

� changing the energy tariff;

� rescheduling production activities

to take advantage of preferential

tariffs;

� adjusting existing controls so plant

operation matches the actual

requirements of the building;

� implementing good housekeeping

policies, in which staff are encou-

raged to avoid energy wasteful

practices;

� investment in small capital items

such as thermostats and time

switches.

4.6 Economic analysis of

Energy Retrofit Projects

The next step consists of a proper

financial analysis of the identified

saving measures. This is extremely

valuable information to assess the

economic viability of the measures.

Probably the simplest technique which

can be used to appraise a measure is

the payback analysis.

The payback period can be defined as

‘the length of time required for the

running total of net savings before

depreciation equals the capital cost of

the measure’. Once the payback period

has ended, all the project capital costs

will have been recouped and any

additional cost savings achieved can

be seen as clear ‘savings’. The shorter

the payback period, the more

attractive the project becomes. It can

be calculated as follows:

AS

CCPB =

where PB is the (simple – i.e. not

discounted) payback period [years],

CC is the capital cost of the measure

[€], and AS is the annual net cost

saving achieved [€]. The annual net

cost saving (AS) is the cost saving

40

achieved after all the operational costs

have been met.

If the payback period PB is less than

the lifetime of the project N (PB<N),

then the project is economically viable.

Therefore, acceptable values for simple

payback periods are typically

significantly shorter than the lifetime

of the project.

4.7 Report writing and

results communication

The main output of an energy audit

procedure is the production of energy

management reports. These reports

perform a vital role of communicating

effectively key information to both

senior and operation managers, as

well as to all the buildings’ users. They

should therefore be tailored to suit the

different needs of their readers.

Reports should be as simple as

possible and should highlight the areas

in which energy wastage is occurring.

The language used should be simple

but accurate, and the report must be

properly structured. Reports should be

published regularly so that wasteful

practices are quickly identified and not

allowed to persist for too long.

In fact, it is very important to identify

the building’s users and stakeholders

and communicate to them the audit

results, as well as to involve them in

the implementation of the saving

measures procedure. There are a

number of reporting techniques that

may be used which ease the

communication with the target audien-

ce, including tables and graphics.

An audit report may include:

� a description of the facility, inclu-

ding layout drawings, construction

details, hours of operation, equip-

ment lists and any relevant mate-

rials and product flows;

� a description of the various utility

tariffs or contracts used;

� a presentation of all the energy

data gathered, together with any

relevant analysis;

� a detailed statement of potential

energy management opportunities,

together with supporting cost-

benefit analysis calculations;

� an energy management action plan

for the facility’s future operation,

which can include a schedule of

implementation for the identified

energy management opportunities

and a programme for the ongoing

energy monitoring and targeting of

the facility.

These audit reports may be comple-

mented by other communication tools,

like presentations, newsletters,

seminars or videos aiming to promote

a wider involvement of the buildings’

users and, therefore, promote more

effective energy saving measures

implementation. A proposal as regards

the contents of an energy audit report

is provided in Table 4.1.

41

Table 4.1: Typical contents of an Energy Audit report

Cover sheet Energy audit report, building and location, person and date of

creation.

Contents Table of contents can also be integrated into the cover sheet!

Introduction General remarks on the energy audit procedure, general remarks on

the energy audit report.

Summary of main

results

Important data and results, selected measures, notes on follow-up

work, remarks

Data collection Data collection (according to the Energy Audit Form used)

Results of stock-

taking Data evaluation

Selected energy

saving measures Improvement measures

Proposal for

further procedure

Expert calculation of economic efficiency, selection of a cluster of

measures. Parallel to this: regular recording of consumption data,

objectives

Appendix Tables used, possibly form explanations, notes, other data recorded

(energy bills, ...)

42

5. BEST PRACTICE

5.1 Step-by-step procedure

for a Standard Energy Audit

To perform an energy audit, several

tasks are typically carried out

depending on the type of the audit and

the size and function of the building.

Some of the tasks may have to be

repeated, reduced in scope, or even

eliminated based on the findings of

other tasks. Therefore, the execution

of an energy audit is often not a linear

process and is rather iterative. A

general procedure can be however

outlined for most buildings, and is

described in the following paragraphs.

This is the procedure recommended to

be followed too in the frame of the

EYEManager approach.

Step 1: Building and Utility Data

Analysis

The main purpose of this step is to

evaluate the characteristics of the

energy systems and the patterns of

energy use for the building. The

building characteristics can be

collected from the architectural/

mechanical/electrical drawings or from

discussions with building operators.

The energy use patterns can be

obtained from a compilation of utility

bills over several years. Analysis of the

historical variation of the utility bills

allows the energy auditor to determine

if there any seasonal and weather

effects on the building energy use.

This data can be retrieved with the aid

of a structured and concise

questionnaire (the Energy Audit “Data

Collection Form”).

Some of the tasks to be performed in

this step [together with the key results

expected from each task] are:

♦ Collect at least three years of utility

data [to identify a historical energy

use pattern].

♦ Identify the fuel types used [to

determine the fuel type accounting

for the largest energy use].

♦ Determine the patterns of fuel use

by fuel type [to identify the peak

demand for energy by fuel type].

♦ Understand utility rate structure

(energy and demand rates) [to

evaluate if the building is penalized

for peak demand and if cheaper fuel

can be purchased].

♦ Analyze the effect of weather on

fuel consumption.

♦ Perform utility energy use analysis

by building type and size (building

signature can be determined

including energy use per unit area

[to compare against typical indices].

Step 2: Walk-through Survey

43

From this step, potential energy

savings measures should be identified.

The results of this step are important

since they determine if the building

warrants any further energy auditing

work. The findings should be tabulated

in another specific form. Some of the

tasks involved in this step are:

♦ Identify the customer concerns and

needs.

♦ Check the current operating and

maintenance procedures.

♦ Determine the existing operating

conditions of major energy use

equipment (lighting, HVAC systems,

motors, etc.).

♦ Estimate the occupancy, equipment,

and lighting (energy use density

and hours of operation).

Step 3: Baseline for Energy Use

The main purpose of this step is to

develop a base-case model that

represents the existing energy use and

operating conditions for the building.

This model will be used as a reference

to estimate the energy savings due to

appropriately selected ECMs. The

major tasks to be performed during

this step are:

♦ Obtain and review architectural,

mechanical, electrical, and control

drawings.

♦ Inspect, test, and evaluate building

equipment for efficiency,

performance, and reliability.

♦ Obtain all occupancy and operating

schedules for equipment (including

lighting and HVAC systems).

♦ Develop a baseline model for

building energy use.

♦ Calibrate the baseline model using

the utility and/or metered data.

Step 4: Evaluation of the Energy

Savings Measures

In this step, a list of cost-effective

ECMs is determined using both energy

savings and economic analysis. The

following tasks are recommended:

♦ Prepare a comprehensive list of

energy conservation measures

(using the information collected in

the walk-through survey).

♦ Determine the energy savings due

to the various ECMs pertinent to the

building using the baseline energy

use model developed in step 3.

♦ Estimate the initial costs required to

implement the energy conservation

measures.

♦ Evaluate the cost-effectiveness of

each energy conservation measure

using an economical analysis

method.

The Energy Audit procedure is

completed with the presentation of all

the energy saving proposals having

the form of a summarized techno-

economical report, which is composed

by the Energy Auditor and presented

to the building/unit manager. Table

5.1 provides a summary of the energy

audit procedure recommended for

commercial and residential buildings.

Energy audits for thermal and

electrical systems are separated since

they are typically subject to different

utility rates.

44

Table 5.1: Energy Audit Summary for Residential and Commercial Buildings

PHASE THERMAL SYSTEM ELECTRIC SYSTEM

UTILITY DATA

ANALYSIS

� Thermal energy use profile

(building signature)

� Thermal energy use per unit area

(or per student for schools)

� Thermal energy use distribution

(heating, DHW, process, etc.)

� Fuel types used

� Weather effect on thermal energy

use

� Utility rate structure

� Electrical energy use profile

(building signature)

� Electrical energy use per unit

area (or per student for schools

or per bed for hotels)

� Electrical energy use distribution

(cooling, lighting, equipment,

fans, etc.)

� Weather effect on electrical

energy use

� Utility rate structure (energy

charges, demand charges, power

factor penalty, etc.)

ON-SITE SURVEY

� Construction materials (thermal

resistance type and thickness)

� HVAC system type

� DHW system

� Hot water/steam use for heating,

cooling, DHW and specific

applications (hospitals, swimming

pools, etc.)

� HVAC system type

� Lighting type and density

� Equipment type and density

� Energy use for heating, cooling,

lighting, equipment, air handling,

water distribution

ENERGY USE

BASELINE

� Review architectural, mechanical,

and control drawings

� Develop a base-case model (using

any base lining method ranging

from very simple to more detailed

tools)

� Calibrate the base-case model

(using utility or metered data)

� Review architectural, mechanical,

electrical, and control drawings

� Develop a base-case model

(using any base lining method

ranging from very simple to more

detailed tools)

� Calibrate the base-case model

(using utility or metered data)

ENERGY

CONSERVATION

MEASURES

� Heat recovery system (heat

exchangers)

� Efficient heating system (boilers)

� Temperature Setback

� Energy Monitoring and Control

Systems (EMCS)

� HVAC system retrofit

� DHW use reduction

� Cogeneration

� Energy efficient lighting,

equipment, motors

� HVAC system retrofit

� EMCS

� Temperature Setup

� Energy efficient cooling system

(chiller)

� Peak demand shaving

� Thermal Energy Storage System

� Cogeneration

� Power factor improvement,

Reduction of harmonics

45

5.2 Case study: Nautical

School

5.2.1 Background

Schools are buildings that have

significant energy consumptions. They

also present unusual problems in

terms of the internal environment.

They generally have short periods of

occupancy, weekdays only with long

holiday periods, i.e. factors that favour

a light construction and intermittent

heating. Many schools have large

glazed areas and high ventilation

requirements, so they represent ideal

objects for insulation and heat

recovery. Being the responsibility of a

single authority in each area, they lend

themselves to central energy

management systems for monitoring

and control.

Lack of specific education and training

in the field of energy efficiency affects

the technical staff in schools and also

decision-makers. These lacks of

education and training have an

important influence in attitudes and

options that affect energy efficiency.

Schools have a widespread trickle

down effect, as information moves out

of the classroom into homes and on to

the community at large. This provides

a perfect platform to move information

on energy efficiency throughout a

community. As students learn about

energy efficiency and its relationship to

cost savings and environmental

improvement they begin to see how

they have the power to create change.

5.2.2 Description of the site

The Nautical School, located in Paço de

Arcos – Portugal (Figures 5.1 and 5.2),

is a public owned school constructed in

1965. Actually, the Nautical School

provides 5 main courses in different

areas, 30 specialization courses, and in

total it has 500 students.

Figure 5.1: General view of the

Nautical School area

When this school were constructed,

the energetic problem was not a “hot”

issue, which is something that can be

seen by the typology of the energy

consumption. As such, the school’s

energy scenario is the following:

• Fluorescent and incandescent lights;

• Single glazed windows with a metal

frame;

• Large wall thickness (± 0.5 m);

• Hot water heaters (boilers);

• Air-conditioning units (splits) in

teachers offices;

• ± 150 computers and 15 printers;

• Electrical and electronic equipment;

• Simulators and navigation systems,

such as radars.

The maintenance of the school is

provided by internal personnel that

combine the buildings’ maintenance

with others tasks. The person involved

in the maintenance does not have any

specific training. Because the school is

46

a public school the management of the

buildings is the responsibility of the

Ministry of Education.

Figure 5.2: External view of the

Nautical School in Paço de Arcos

5.2.3 Description of the work

The purpose of the energy audit was

to identify energy saving opportunities

among building systems and

equipment. The goal of the energy

audit was to identify life-cycle, cost-

effective energy saving measures by

evaluating the overall efficiency of the

buildings’ systems (HVAC, lighting,

envelope) and the efficiency of

individual components comprising

those systems (pumps and motors,

lamps and ballasts, windows).

For this specific case, it was decided to

make a walk-through energy audit that

consists in a visual inspection of the

Nautical School in order to determine

operation and maintenance energy

saving opportunities, as well as gather

information to determine the need for

a more detailed audit. The audit was

conducted by ISQ staff and the school

management person, and it was made

as a pilot project in the frame of the

EU funded INTERREG IIC Project

SoustEnergy (www.soustenergy.net).

The building’s energy consumption

over the last year was also checked.

To develop the audit 3 different phases

were defined. First, the collection of all

information related to the school.

Second an audit was performed, where

it was recorded what equipment and

systems are installed, how the various

equipment and systems interoperate

and consume energy. Then the evident

conditions of the installed equipment

and systems were determined and

recorded and the energy conservation

opportunities were suggested by virtue

of these existing conditions.

More specifically, the information

gathered was information about the

building, its systems and equipment,

as well as the O&M procedures used.

Basic information about the building,

such as its use, occupancy, number of

floors, layout, age, and hours of

operation provides insight into the

complexity of the building. Then, a

floor-by-floor, and a room-by-room

investigation was conducted in the

Nautical School during a site visit to

verify all preliminary building

information. The building envelope was

examined, each equipment room, and

finally the space conditions.

After accomplishing the above steps,

the final phase was the suggestion of

energy conservation opportunities

using the information gathered and

verified during the site investigation.

In order to ensure that the energy

consumption data are correct, quality

control is critical when conducting an

energy audit. The tools used for

measuring energy consumption and

efficiency in the audit were:

47

• Voltmeters, wattmeters, power

factor meters, combined energy/

demand meters, and other power

monitoring equipment, as

appropriate, to determine electrical

load characteristics.

• Thermometers and surface

pyrometers to measure air, liquid,

and surface temperatures.

• Psychrometers and hygrometers to

measure relative humidity.

• Measurements of the combustion

efficiency were also made to

determine the composition of

boiler’s flue gas.

The obstacles that were raised during

the implementation of the energy audit

were the following:

1. Difficulties to set a date to have a

meeting and starting the audit;

2. The availability of the person in

charge of management of the

building was very restricted.

How these obstacles were overcome?

It was necessary to put some pressure

to the school responsible in order to

“open” the school doors to ISQ. It was

explained that this pilot project was an

important step to help the school to

reduce its energy costs and become

more appellative to the students, more

comfortable and energy efficient.

5.2.4 Outputs of the Energy

Audit

Based on the analysis of existing

conditions, it was possible to identify

and evaluate potential energy savings

measures, for building systems,

equipment, and O&M. This includes

determining the energy and demand

savings for each energy savings

measure, as well as the financial

viability of the proposed upgrade.

The total energy consumption in the

Nautical School was found to be

482,000 kWh/year (equivalent to

30,212 €/year), according to the

desegregation presented in Figure 5.3.

Figure 5.3: Nautical School energy

desegregation by energy source

The propane gas is the fuel that the

boiler uses to heat water for indoor

heating the classrooms, swimming

pool and gymnasium. Electricity is

used in several equipments as shown

in Figure 5.4. According to the audit’s

findings, the areas with potential for

energy savings are listed in the

following paragraphs.

Figure 5.4: Electricity consumption by

end-use relative importance

Building Envelope: A significant

amount of energy is wasted by air

infiltration and exfiltration through the

48

building’s envelope. Infiltration is

outside air that enters a building

through cracks and other openings in

the building envelope, including open

windows and doors. Exfiltration is

conditioned air that is lost to the

outside through the same openings.

Because the building is of some age,

the air leaks (cold and/or hot) are

significant and several points exist

were it is necessary to replace leakage

system. Rubbers of the doors and

windows must be replaced in order to

avoid energy losses in these points.

Also the broken glass windows must

be replaced. It is further recommended

to replace the single glazing windows

with metal frame by double glazing

windows with aluminium frame. With

this measure it is expected to reduce

the total energy consumption between

5 to 7% (24,100 to 33,740 kWh/year).

Lighting: Lighting is the largest

portion of Nautical School electricity

bills. The lighting systems are mainly

composed by fluorescent (90%) and

incandescent lights (10%). It was

derived that this school was designed

with only initial costs in mind, without

knowledge of how the space would

ultimately be used and subdivided, and

without the benefit of new

improvements in lighting technology.

What was detected is that in some

classrooms that have large windows

energy is wasted by providing more

light than is necessary for the space.

At the same time, the lamps and

ballasts used are inefficient.

According to the information collected

during the audit, the next table shows

the lighting scenario in numbers (for

calculating the costs, an electricity

tariff of 0.062 €/kWh is considered):

Nr Installed power (W)

Absorbed power (kW)

Working hours/ day

Days/year

Annual consumption

(kWh)

Annual cost (€)

Fluorescent lights

234 58 17.9 14 320 80192 4971.90

Incandescent lights

110 100 13 12 365 56940 3530.28

According to that, the best solution is

to make an upgrade to the lighting

system, replacing the fluorescent and

incandescent lights with inductive

ballasts by compact fluorescent with

electronic ballasts. In some cases it

was recommend the installation of

light sensors to adequate the light

inside the classroom to the comfort

levels, as studies have shown that

student’s productivity declines when

lighting is reduced to levels below

those needed for proper performance.

The replacement of the fluorescent and

incandescent lights listed previously by

the compact fluorescent lights (CFLs)

will provide a tremendous economy.

The compact lights proposed are:

49

Nr Installed power (W)

Absorbed power (kW)

Working hours/ day

Days/ year

Annual consumption

(kWh)

Annual cost (€)

234 18 4.212 14 320 18869.76 1169.93 CFLs

110 12 1.32 12 365 5781.6 358.46

The investment will be paid in less

than 1 year. The replacement of light

bulbs represents a reduction in lighting

costs of 6974€/year. Comparing with

the total energy consumption, the

economy in kWh is 23% (112480.64

kWh). If the replacement of the

inductive ballasts by electronic ballasts

is considered the energy consumption

will be reduced even more. The

investment to replace the lighting

system in Nautical School is a priority

measure for the energy efficiency.

Human Interaction: People also have

a great effect on lighting efficiency.

Lighting left on when it is not needed

wastes a great amount of energy. With

a small change in the behaviour of the

students and teachers the energy

consumption will be also reduced. If a

regular maintenance program will be

set up the operation the indoor lighting

condition will be increased. With this

measure it is expected to reduce the

total energy consumption by 1% (4820

kWh/year).

Heating system: The space heating

in the Nautical School is provided by a

hot water boiler that uses propane

gas. Because the utilisation of this

system is mainly to provide hot water

to the teacher’s office, administrative

offices and bathing facilities of the

gymnasium, it was not considered

necessary to improve the system.

Even so, an environmental benefit

exists to switch the fuel to natural gas.

Computers and Printers: The

Nautical School has several classrooms

and other offices that have computers

and printers. Their number is:

Nr Installed power (W)

Absorbed power (kW)

Working hours/ day

Days/ year

Annual consumption

(kWh)

Annual cost (€)

Computers 150 110 16.5 14 365 84315 5227.53

Printers 15 100 1.5 14 365 7665 475.23

50

If the various energy saving features

that can automatically shut down the

monitor and the hard drive after

specific periods of inactivity are used,

it is possible to save energy every time

each person (students, teachers,…)

leaves the office or when these people

are not using their computers.

When a typical monitor is shut down,

its energy use reduces to less than 1

watt (W), leaving only the hard drives

using power – around 50 W. When the

system hibernates, the hard drive is

shut down and total energy use of the

computer is reduced to less than 6 W –

approximately 5% of full operating

power. By using the computers in a

more efficient way it is possible to

increase the energy efficiency of the

computers, reducing the energy

consumption by 15%. This means that

the Nautical School will have an

economical benefit of 860€ per year.

51

BIBLIOGRAPHY

Beggs, C., 2002. Energy: Management, Supply and Conservation. Butterworth-

Heinemann, Elsevier Science.

EI-education, 2008. EI-Education guidebook on energy intelligent retrofitting.

Available at: http://ei-education.aarch.dk/

European Commission, Directorate General XII, (1995). Energy Management

System.

EnerBuilding, 2008. Energy efficiency in households Guide. Enerbuilding.eu Project,

May.

EU, 2008. The EU Energy Label. Available at: http://www.energy.eu/#energy-focus

EU TopTen, 2006. Available at: http://www.topten.info/.

GREENBUILDING, 2008. GreenBuilding Guidelines and Technical Modules. Available

at: http://www.eu-greenbuilding.org.

GreenLabelsPurchase, 2006. GreenLabelsPurchase: making a greener procurement

with energy labels. Available at: www.greenlabelspurchase.net.

ISO, 2008. Building environment design – Guidelines to assess energy efficiency of

new buildings – ISO 23045:2008. International Organization for Standardization,

Switzerland.

Krarti, M., 2000. Energy Audit of Building Systems – An Engineering Approach. CRC

Press.

52

ANNEX 1

Typical Electricity Use per Appliance Typical rate of energy use, in Watts, by appliances on “stand-by” compared to “on”. Although the data are approximate, there is enough information to compare the energy needed to operate appliances both while "on" and on "stand-by". From UPPCO and Directgov - UK

Appliance Standby On

Answering Machine 3 3

Clock Radio 2 10

Computer 50 270

Computer Monitor 11 70

Laptop 2 29

Microwave 3 1500

Mobile Phone Charger 1 5

Video cassette recorder (VCR) 5 19

Stereo 12 22

Broadband Modem 14 14

DVD Player 7 12

Television 10 100

Digital TV Box 5 6

Formula for estimating Energy Consumption

You can use this formula to estimate an appliance's energy use: (Wattage × Hours Used per Day ÷ 1000 = Daily Kilowatt-hour (kWh) consumption (1 kilowatt (kW) = 1,000 Watts) Multiply this by the number of days you use the appliance during the year for the annual consumption. You can then calculate the annual cost to run an appliance by multiplying the kWh per year by your local utility's rate per kWh consumed.

Example:

Personal Computer and Monitor: (270 + 70 Watts × 4 hours/day × 365 days/year) ÷ 1000 = 496.4 kWh × 8.5 ¢/kWh = $42.2/year

53

ANNEX 2

Recommended luminance levels according to the premises and uses

Premises Luminance

(lumen/m2=lux)

General outdoor, rural roads 7-12

Gardens, industrial zones 15-25

Streets, highways 30-50

Entrances, parking 50

Panoramic outdoor, store, reception room, corridors,

staircases, washrooms, general tasks 150

Dining rooms, public premises 200

Meeting rooms, laundry, offices, hotel rooms, tasks requiring

precision 300

Work stations, large stores, laboratories 500

Reading, drawing, classroom, kitchen, tasks involving detail 750

Shop windows 1000-3000

54

ANNEX 3

Energy values and CO2 emissions of different fuels (from the BIOMASS Energy Centre)

Fuels for heating and power (the figures correspond to the CO2 emitted by full combustion of each fuel, per unit of energy)

Direct CO2 emission from combustion

Annual total CO2 emissions to heat a typical house (20,000 kWh/yr)

Fuel

Net calorific value

(MJ/kg)

Carbon content (%)

kg/GJ kg/MWh kg kg saved compared with oil

kg saved compared with gas

Hard coal 29 75 95 345 9680 -2680 -4280

Oil 42 85 73 264 7000 0 -1600

Natural gas 52 73 51 185 5400 1600 0

LPG 49.7 82 60 217 6460 540 -1060

Electricity (UK grid)

- - 128 460

See note 1 10600 -3600 -5200

Wood chips (25% MC)2

14 37.5 98 354 500 6500 4900

Wood pellets (10% MC)2

17 45 97 349 660 6340 4740

Biogas (60% CH4, 40% CO2)

20 56 103 370 - - -

Notes: 1 For electricity, the value of CO2 emitted per unit depends on the different fuels used for power production. The environmental profile of the electricity distributed is available on national information sources. For the UK: www.electricity-guide.org.uk/fuel-mix.html 2 For wood fuels, it is important to observe the influence of the total moisture on the wood density: the more water per unit weight (MC), the less fuelwood. Fuels for transport

CO2 emission on combustion Fuel

Net calorific value

(MJ/kg)

Density (kg/m3)

Energy density (MJ/l)

Carbon content (%) g/litre kg/gal g/MJ

Petrol 44 730 32 87 2328 10.6 72.8

Diesel 42.8 830 36 86 2614 11.9 72.6

LPG (mainly propane)

50 510 25 82 1533 7.0 61.3

Bioethanol (from wheat)

27 789 21 52 1503 6.8 71.6

Biodiesel (from waste vegetable oil)

37 880 33 77 2486 11.3 75.3

55

Agenzia per l'Energia e l' Ambiente della Provincia di Perugia

Str. corcianese,218 - Centro Direzionale Quattrotorri Torre E

Energikontoret Regionförbundet Örebro

NetCity, Forskarvägen 1

SE-701 83 Örebro, SWEDEN

Centre for Renewable Energy Sources

19th km Marathonos Avenue

Agencija za prestrukturiranje energetike, d.o.o.

Litijska cesta 45, SI-1000 Ljubljana

SLOVENIA

National Institute for R&D in Informatics (ICI)

Project partners

Noesis European Development Consulting

Via N. Sauro, 4b, scala B

Agencia Energètica de la Ribera

Plaça Argentina,1

Istituto d'Istruzione Superiore 'L. DA VINCI'

Franca Via Tusicum

Tullängsskolan Örebro

Tullängsgatan 7, Box 31170,

Doukas School

Mesogeion str. 151,

Šolski center Velenje – School Center Velenje

Trg mladosti 3

3320 Velenje, SLOVENIA

Scoala cu clasele I-VIII Nr. 45 "Titu Maiorescu"

Calea Dorobantilor Nr. 163,

21 General comprehensive school "Hristo Botev" 12 Ljubotrun, Sofia

BULGARIA

Agência Municipal de Energia de Almada

Rua Bernardo Francisco da Costa, 44

Podkarpacka Agencja Energetyczna Sp. z o.o.

ul. Szopena 51/213

PAIDEIA Foundation

76-A, Evlogi Georgiev Blvd.,