unido tool kit 4-textbook

U N I D O C L E A N E R P R O D U C T I O N T O O L K I T

UNITED NATIONS INDUSTRIAL DEVELOPMENT ORGANIZATION

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Energy analysis

Main directorym

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Textbook 4 - Energy analysis

4- BACKGROUND MATERIAL

4 Textbook

4.1 Aims and goals of "Energy Analysis" Aim of the dossier

With the aid of this manual and the worksheets you will be able to create and maintain an energy data base for your company in order to be able to use a corporate energy management system as a tool for optimising the overall company.

Since the oil price shock, it has become a matter of course for large companies requiring large amounts of energy to install an energy management system. Whereas small and medium-sized enterprises rarely attend to these matters. The aim of this brochure is to describe the work entailed by a corporate energy analysis that will serve as a basis for a company’s energy management system. The following table compiles the key aspects of a company’s energy management system.

It comprises the five areas:

1. Organisation

2. Analysis and planning

3. Monitoring

4. Consulting

5. Implementation

Area Contents

Organisation • Installation of an organisational unit focused on energy related matters

• Clear guidelines concerning responsibilities (organisation chart) and funds

• Integration of this unit into investment related decisions

Analysis and planning

• Collection and documentation of data concerning energy supply and utilisation in the company

• Description of the energy situation (annual update)

• Survey of weaknesses and saving potentials

• Creation or commissioning of energy analyses

Measures for achieving an efficient corporate energy system

Authors:

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Area Contents

(measurement of individual facilities or machines)

• Elaboration and planning of energy saving measures

Monitoring • Monitoring of energy conversion equipment and energy consumers

• Elaboration of energy benchmarks (development)

• Creation of company comparisons concerning energy efficiency (e.g. benchmarks)

Consulting • Description of energy situation (energy report to management)

• Consulting concerning conclusion of supply contracts

• Market observation

Implementation • Implementation of energy saving measures

• Maintenance of energy facilities

The focal points of the above areas listed as an example (see table) provide a good insight into the steps that need to be taken to install an energy management system.

The contents of this brochure are focused on the core areas of the energy management system:

Analysis (including documentation) and monitoring Major issues of an energy management system

The following focal points are established:

• Collection and documentation of data concerning energy supply and utilisation in the company

• Description of the energy situation (annual update)

• Elaboration of energy benchmarks as a monitoring and decision-making tool

• Identification of options intended to save energy and energy costs

As mentioned above, installing organisational units focused on energy is an important precondition for guaranteeing an efficient energy management system. Volume 2 of this series “Team, policy, motivation” has already dealt with the questions of staff motivation and responsibility. Please read this textbook as well with implementation of an energy management system in mind.

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Textbook 4 - Energy analysis Energy- and

Material flows "Energyflows" are more difficult to detect, but follow similar rules like material flows, which finally lead to waste. Thus the dealing with this issue in the work shop and in the company is quite similar:

• Because you cannot see energy you have to use measuring devices. Sometimes they already exist or data are gathered, recorded and can be accessed by the energy supplier.

• The energy consumption is determined from a large number of plants and equipments. These equipments are planned, installed and maintained from companies which can also be part of the analysis.

• A utility is obliged to provide all services which are required. Therefore they mostly pay working costs and basic-services costs. Due to a better allocation of demand, costs can be saved without having to limit services.

• Every type of energy, that is converted in a company, (e.g. measured in kilo watt hour / kWh) leaves the company in the form of heat.

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4.2 What are the main components of the corporate energy system? What is the basic approach?

Objectives of the corporate energy analysis

Baiscally, a company’s energy system covers six areas. The aim of CP is not to see energy purchase (input) as an unchanging constant, rather the idea is to elaborate measures designed to increase efficiency in terms of conversion, distribution and utilisation of energy and by means of heat recovery. The prime objective is to create the company’s product or service with a minimum energy input. Thus, this background information seeks to focus on the energy service and not on the use of energies.

Structure of the corporate energy system

Disposal

Heat recovery

Utilisation Distribution ConversionSupply

The following steps are required:

In all six areas, data is collected on the following:

• type, number and characteristics of facilities • type of energies and energy consumption

For energy purchase

• analysis of energy consumption in certain periods

For all areas

• interpretation of data (development, benchmarks) and • suggestion of possible solutions to efficient energy utilisation

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Energy units

The energy consumption is measured in Joule (J, kJ, MJ, GJ). A further common unit is the kWh, whereas 1 kWh equals 3.600 kJ. Work J = Joule

1 kWh = 3.600 kJ

Power Watt = J/s

conversions at end of document

Energy sources are also indicated in kg, Nm³ or l. These units can be transferred in kJ or kWh for the respective fuels – see conversion table at the end of this document.

Besides the energy consumption the energy power is also often very important. It indicates which work can be done within a specific time and is usually measured in Watt (W, kW, MW, GW).

4.3 Gathering of data and energy saving potentials

Before you start collecting data and analysing, observe the following tips:

• Find out what records on energy consumption and consumer structure (e.g. machinery lists) are already kept at the company. Use your staff

knowledge for the purpose of energy saving

• Also, ask whether the company already has plans, programs, measurements, etc., to increase efficiency.

It makes sense to check this first so as to avoid double-tracking. Also, when talking to staff, you will often obtain important information concerning realistic energy-saving potentials. The existing records on energy consumption and consumer structure are required for the following analysis.

Ongoing data collection

The technical energy data, from purchase (input), to utilisation, and disposal (output) are analysed in the followed chapters. In each case the analysis will proceed from the general to the specific, indicating possible analyses and interpretations after compilation of the data.

4.3.1 Energy data

The annual energy input and annual energy costs should be collected separately for each type of energy.

Procedure?

Where to obtain the data?

Aids can include e.g. bills of energy supply companies (electricity, district heating, gas), heating oil/diesel suppliers, sales by the company’s own petrol station, own electricity generation, log book.

Good consultation in terms of electricity, gas or regional district heat can save significant costs. This, however, should be examined in the particular case.

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Textbook 4 - Energy analysis Specific energy use - indicators

The best way to evaluate these data?

For development of the company in terms of efficiency and effectiveness, above all standardised quantities will play an important role, i.e. specific consumptions, so-called benchmarks (see also volume about indicators and controlling): e.g., for a brewery, heating oil consumption per hectalitre of beer. This reference quantity may differ quite substantially depending on the particular type of energy and company. However, it should be chosen in such a way so as to be able to track the development for the purpose of greater efficiency. Usual reference quantities are: production volume, turnover, number of staff, heated surface, volume transported, mileage, etc.

Benchmarks tell you more

The aim of any company should be to reduce specific energy consumption. For expanding companies, benchmark trends are the only reliable indicator of energy efficiency, while total energy consumption is not.

The characteristics of the specific consumption can already be used for the analysis and control of the energetic situation in the company.

• Has the specific consumption changed? Getting Indicators

Interpretation of indicators

• Is the allocation base for the calculation of the specific consumption well chosen?

• If the specific consumption has increased:

− What could be the reason? Which areas expanded? Can the reason be found there? Was there any substitution of energy sources?

• If the specific energy consumption has decreased:

− Was it a selective energy saving measure? Were the targets met? Or was it shifting from one energy source to the other?

• Due to the characteristics of indicators the situation can be assessed, without making a statement whether this consumption is too high or not. Where do I get information about how good I am?

− Asking colleagues for data from the sector

− Asking plant manufacturer for data

− Literature (research, magazines)

− calculations

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Textbook 4 - Energy analysis Collecting of Data

Ewnergy carriers to be traced at the company

Data should be collected separately for the following types of energy: electricity (energy supplier), own electricity generation (hydropower, photovoltaics); natural gas, heating oil (heavy, light, extra light), fuels (diesel, petrol), biomass, solar power, district heating (see also at worksheets).

Particularly, note the fact that there are important areas such as purchased fuels that are often not directly allocated to energy consumption. These values should also be recorded as they are generally the most important source of energy, for example in service companies, and fuel consumption is already the second largest factor in per cent in Austria.

Transport is a major energy consumer

Annual profiles

The development of monthly consumption in the form of an annual profile shows: Interpretation

of annual developments

• the winter-summer ratio for the purpose of estimating heating/cooling and process heat percentages

• if several years are taken into account, displacement of individual

energies (e.g. heating oil consumers are replaced by electricity consumers),

• the possibility of analyzing energy carriers, e.g. for combined heat and power generation

• Are there months with significant consumption peaks? Can they be avoided (e.g. press, dryer, bath, air conditioning, etc)?

The appropriate data should be taken from energy supplier bills and the company’s own records.

What special analysis of the annual profile is possible for electricity? Development of output

Power is a substantial cost factor

Electricity purchases are billed on the basis of two quantities:

• Power (kW) • Consumption = work (kWh)

These quantities can be found in electricity bills (or annual statement). Particularly power (kW) must be divided into billed power and power actually required.

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Use peak load control

Large companies usually have a so-called power management system that ensures that a certain maximum power is not exceeded. If required power is higher, consumers are shut down temporarily in order of priority. Companies with a power management system should also check proper functioning of their system.

Elektrische Leistung am 15.5.1998

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Is there a big difference between the monthly peak load and the calculated average power? If yes: Can it be change with a different production plan (cheapest solution)? Would demand management make sense? (obtaining offers from companies in the sector. As a target value you can assume that such a plant is available at a price of 3.500 € and more)

If reactive current costs are high (see electricity bill for details) it makes sense to avoid these costs by installing a compensation device. Specialised firms offer various designs and efficiency calculations.

Weekly/daily statistics

Record the daily statistic for at least one day. Take the day with the highest daily consumption or the day with the highest daily peak. Identifying

power peaks The day with the highest daily consumption need not be the day with the highest daily peak. Peaks may be entirely independent of energy consumption when repairs, test runs, presses, etc. require large amounts of power.

In order to collect data on electricity, companies with an electronic 1/4-hour meter simply have to call their energy supplier as they will provide these data for the peak consumption days, mostly free of charge. Energy suppliers sometimes also offer other companies (cost free) measurement of power consumption statistics for a 7-14 day period.

How to interpret weekly/daily statistics

• Do peaks cause bottle-necks in supply?

• Particularly with regard to electricity: can these peaks (= power price) be avoided?

• Is energy consumption necessary outside production hours? Or can this be saved?

• Is energy consumption high at weekends? Can this be avoided? (e.g. by switching off compressors, boilers, heating baths, night-time reduction at weekends also during the day (however, observe the development of outside temperature!))

• Is consumption particularly high on any particular weekday? Can this be avoided? (This is particularly important for seemingly necessary plant extensions that can possibly be avoided.)

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Textbook 4 - Energy analysis 4.3.2 Conversion

So far you have only analysed energy purchase (input). Now we will document and analyse the next area of the company’s energy system, conversion.

Conversion equipment includes: heating boilers, steam boilers, district heating interconnecting stations, refrigerating equipment, combined heat and power generators (e.g.: block-type power plants), and direct fuel consumers (e.g. gas dryers).

Practically every company has energy converters in the form of heating or steam boilers. Thus, this area is particularly important in terms of efficient use of energy – see also at worksheets.

What information is important with regard to heat generation in boilers? How can the information be interpreted?

The following table lists the basic data and thus a possible interpretation.

Basic information

Interpretation, measures

Rated capacity Is the boiler utilised to a good level? (e.g. for heating, more than 1200 full-load hours)

Fuel type and consumption Is it possible to switch to a more environmentally friendly fuel?

Flow temperature (or pressure in steam boilers)

Are flow temperature/pressure correctly adjusted to the consumers or could they be reduced? (The higher the flow temperature, the greater the losses.)

Operating hours See rated capacity Firing efficiency Is the efficiency of the boiler regularly measured

(chimney-sweep)? Does efficiency match the manufacturer’s specifications? Is the boiler regularly cleaned?

What information is important for central refrigeration equipment? How can the information be interpreted?

The following table lists the basic data and thus a possible interpretation.

Basic information

Interpretation, measures

Rated capacity Annual electricity consumption Operating hours

Operating hours should be between 4000 and 6000 h for well-designed equipment. Is rated capacity adequate? Is the target refrigeration temperature maintained on hot summer days?

Outside/condensation temperature difference

At outside temperature > 10-15°C, condensation temperature should not exceed 10-15°C above outside temperature. If this is the case, check the heat exchangers (control, design, etc.)

Refrigerator/evaporation temperature difference

The temperature difference between the refrigerator and evaporation temperature should be < 10°C (depending on the specific application up to < 4°C).

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Textbook 4 - Energy analysis 4.3.3 Distribution

The next step after conversion of energies in the company is energy distribution. Particularly “heat distribution” (hot water, steam) can involve major losses.

Line Losses

Thus, check whether pipes are insulated (flow and return). The following example is designed to show the importance of insulation. A heating system with a flow temperature of 80°C and a return temperature of 20°C has a heat loss of 31,2 kW or almost 20% of effective heat output in 200 metres of uninsulated piping. With a 50-mm insulation, heat loss in 200 metres of piping is 3,6 kW or 2%.

Importance of insulation

Steam traps in steam consumers must be checked regularly, also consider whether they should be replaced by new ones (better use of steam).

Check steam traps

Pay special attention to fittings as they have a large surface and can thus cause major losses.

The idea that radiated heat is not really lost is very deceptive as:

• generally pipes are located at the top and thus heat really is lost,

• heat is not delivered where and when it should be, and • overheating can occur in individual areas (additional burden on air-

conditioning, unpleasant working climate).

4.3.4 Consumers

Worksheet 4-4 lists the most important consumers, their installed load, operating hours and consumption. You should record a total of at least 80% of purchased power. The important thing is to divide consumers according to their applications.

Recording Consumers

For heat, according to: • process heat, heating, hot water, air-conditioning

For electricity, according to: • refrigerating equipment, other cooling equipment, electric heating, hot

water, lights, process heat, drives (mechanical work) For central refrigeration unit, according to: • the individual cooling points

In addition to the application, survey installed load and full-load hours. With the aid of installed load and full-load hours (estimate for small aggregates, large machines usually have operating hour meters), it is possible to compute total consumption. Thus, this break-down allows you to allocate consumption to consumer groups and specific applications. There is also a column for “Notes”. Use this column to record details on energy saving and any necessary renewal or maintenance work identified by the company’s electrician, for example, and which can be collected on this form.

The aim is to identify potential savings

However, before collecting the data, read about the possible interpretations so that you also collect any information that may be needed for this purpose.

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How can these data be interpreted?

General:

• An important point is to record and document equipment and machinery.

Aim of the survey

• The collected data form the basis for cost calculations in order to be able to allocate energy consumption correctly to the appropriate consumers. For example, this may induce individual departments to realise potential savings.

• Typical energy consumptions for individual areas should be obtained from suppliers. At all events, machines older than 5 to 10 years can generally mean significant energy savings due to fast developments in the field of microelectronics and sensor technology (e.g.: frequency converters for speed control).

• With the aid of the consumer structure, it is possible to prioritise energy-saving measures and purchasing guidelines.

• Suppliers will provide energy consumption rates for good machines (efficiency of boilers, energy consumption of refrigerating equipment referred to characteristic size and nominal temperature). A comparison with these data will allow you to decide whether or not to investigate in greater detail.

Heating/air-conditioning:

• Are heating registers regulated according to demand (thermostatic valves) and should individual areas of the company be regulated separately?

Starting points for energy saving

• Is room temperature adjusted to demand? (cooler in winter, warmer in summer, lowered at night and at weekends, allow greater variation of parameters, e.g. a rang of minimum +/- 10 %)

• Are inside sources of heat and humidity avoided in air-conditioned areas?

• Do the air-conditioned areas have sunshading facilities?

• Do fans have variable speed drives in order to adjust the volume of air to demand?

• Are gates closed automatically? Is it ensured that windows and doors stay shut?

• Is there adequate vertical distribution of heat so as to avoid heat accumulation near the ceiling?

• Does the company take specific measures to ensure minimum consumption in process heat equipment? I.e. minimum volumes of air in dryers, minimum volume of water in washing machines, bath covers, vat insulation, ...

• Is one main objective with regard to process heat equipment a cascaded system of heat utilisation?

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Power consumers:

• Are machines and equipment adjusted to demand? Avoid partial load operation of machines and equipment as least loss occurs at the rated operating point; i.e.: adjusted drives, star-delta control, V-belt pulleys and frequency converters.

Starting points for energy saving

• Is consumption regulated to demand e.g. for fans (half speed equals a 75% reduction of power)?

• Is the compressed-air compressor located in a cool room? Is the pressure level kept as low as possible? If possible, is compressed air avoided (most expensive form of energy!)?

• Are intake grids and nozzles regularly cleaned in order to reduce pressure loss?

• Are lights adjusted to demands in terms of times and sites? Are light casings and reflectors regularly serviced and cleaned?

• If lights are old (older than 5 to 10 years) it generally pays off to install a more efficient lighting system. Analysis services are offered free of charge by firms in this line of business.

4.3.4.1 Division of consumption according to applications and energies

With the aid of annual energy data and consumer data, it is possible to allocate energies to the following applications

• process heat

• heating

• hot water

• refrigeration

• lights

• other power consumers

• transport

This provides a good overview of the company’s energy system. Once you have identified the energy consumption of the individual areas, you can proceed to set priorities for the further analysis. What is more, these records are essential for ECO-auditing.

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Textbook 4 - Energy analysis 4.3.5 Disposal of Energy

The term disposal used in the context of energy does not match the usual meaning of the word, but is intended to illustrate the fact that for example equipment is also required to dispose of waste heat. However, this equipment is not only a source of loss but also causes costs and is time-consuming which is why it should be separately analysed. Investing in energy-saving technologies can reduce the amount of time and costs required for disposal (from the symptom to the cause: for example, waste heat from computers has to be removed by the air-conditioning system, i.e. low-loss computers can pay off as a result of lower costs of air-conditioning).

Waste heat needs to be disposed of

Thus, briefly describe the way the energy used leaves the company. Pay particular attention to the utilisable temperature level. Use worksheet 4-5 for this task.

Essentially, we will look at the following areas:

• exhaust gases (e.g. boiler, drier)

• waste water (before mixing, i.e. straight from each system)

• refrigerating equipment (e.g. waste heat from condenser, product cooling)

• other losses (e.g. outgoing factory air)

This allows us to identify avoidable energy consumption and, if necessary, exploit it in the form of a heat recovery system.

4.3.6 Heat Recovery

Worksheet 9 will indicate

• possibilities of cascaded utilisation of heat,

• connecting flows by means of heat exchangers,

• current waste heat utilisation,

• possibilities of improving waste heat utilisation

Utilisation of waste heat from equipment, better still in the aggregates themselves (e.g. air preheating, counter-flow water preheating), is of great importance for a high level of efficiency.

The so-called pinch technology is one way to link heat flows in process aggregates. This also allows you to plan effective deployment of heat pumps. If required, consulting firms in this area will provide the necessary information.

Also the waste water often contains enough heat. Even at low temperatures heat recovery mostly pays off.

Waste water and exhaust air contain heat Example: At a cooling down of 1 m³ waste water and simultaneous pre-

heating of fresh water of 10 °C gives you a saving of approx. 1,5l heating

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Textbook 4 - Energy analysis oil. For strongly polluted or solid containing waste water, a special heat exchanger is recommended.

A frequent waste heat source are air compressors. In this case the cooling should occur with oil or water instead of air. The oil or water can then be used to pre-heat fresh water.

4.4 Typical energy applications with optimising potentials

In this chapter typical question for 4 common energy applications are discussed - boiler/steam system, cooling/freezing, air pressure and illumination – which will give a possible optimisation potential. The questions as well as the mentioned energy application represent just a small selection. A detailed description would go beyond the scope of this volume.

4.4.1 Boiler, steam system

• Is the condensate returned? (contains up to 12% of the energy)?

• Is the combustion air pre-heated?

• Is the fresh water pre-heated through a heat recovery?

• Is the proportion of air set correctly? (no air surplus, no leak air, but still complete combustion)? Does the air amount controller work?

• Are the heat surfaces maintained and cleaned sufficiently (1 mm fouling increases the exhaust air loss and thus the energy consumption of approx. 5%)?

• Are steam losses avoided? Does the condensate discharge work?

• Is vapour pressure in the system adjusted to the temperature applications (unnecessary high pressure and thus high temperature means losses)?

• Is the boiler insulated sufficiently (especially the front)?

• Is the size of the boiler correctly designed (unnecessary high power causes unnecessary start up-, shut down- and operation losses)?

• Is the condensate container insulated?

• Are the steam-/warm water pipes insulated? Also shifter, valves, flange and distributor (are there unlockable clamp insulators)?

• Can modern, high efficient boilers be installed?

• ...

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Textbook 4 - Energy analysis 4.4.2 Cooling

• Is the illumination reduced or switched off automatically in the cooling rooms?

• Is it assured that no warm products are stored (at first they should be cooled down to room temperature if possible)?

• Is it assured that the defrosting cycle is operated sufficiently but not too often (check the setting)? Is it assured that there is not ice on the vaporiser?

• Are plastic curtains or rapid closing doors used to lower losses?

• Is the required temperature in the cooling room recorded and adjusted to the need (1 °C can save up to 4 % electricity)?

• Covering of open cooling devices?

• Are the door seals ok?

• Are the opening times minimised? Cooling energy is expensive and requires energy consumption

• Are the cooling devices maintained and cleaned constantly?

• Is the temperature in the condenser as deep as possible?

• Is it checked whether the discharged air in the condenser can be reused?

• ...

4.4.3 Compressed air

• Are the compressors and dryers switched off after closing hour?

• Can the pressure be maintained after closing the valves?

• Are the pipes and plants checked in terms of leaks (constant check after closing hour or at the weekends)?

• Have you done a compressor measuring – delivery amount and pressure (that is offered by many compressor manufacturers)?

• Is the pressure reduced to the required minimum?

• Is it assured that there is no higher pressure just for a single consumer (an additional pressure net for this consumer)?

• Is the intake air temperature held as low as possible (the colder the higher the efficiency? Outdoor intake)?

• Do you avoid to use compressed air for cleaning?

• Are the air intake filters cleaned regularly (avoiding of a too large pressure loss)?

Compressed air is one of the most expensive energy • Is it possible to separate areas in the compressed air net?

• Is it possible to cool the compressor with oil or water so that the heat could be reused?

• Is the waste heat from the air-cooled compressors reused in the winter (e.g. in the working halls)?

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Textbook 4 - Energy analysis • Is it possible to use electronic tools instead of pneumatic ones.?

• ...

4.4.4 Illumination

• Is it assured that just necessary illumination is on?

•• Is the outdoor- and display-window illumination controlled (motion detector, timer)? Is daylight used as much as possible?

• Are lamps/lights and windows maintained and cleaned constantly?

• Are the rooms arranged wisely in terms of illumination?

• Are energy saving lamps used (normal bulbs have a low efficiency; just 1-2%, halogen lamps 1,3-3% fluorescent or energy saving lamp10-15%) ?

• Are electronic power starter units used for fluorescent lamps?

• Are lights sufficiently equipped with reflectors?

• Have you ever measured the illumination intensity at your work stations?

• Are there enough switches?

• Can you switch the different working stations separately?

• ...

4.5 Utilising renewable energies

With regard to the stabilisation of greenhouse gases, in addition to increasing efficiency, many countries start striving to switch to renewable energies. Individual cities and regions have even undertaken to halve CO2 emissions by 2010. In the spirit of an offensive environmental policy, companies are called upon to declare their own activities in this area.

Renewable energies and climate policy

For this reason, the analysis should document what renewable energies are used for what purpose and what percentage they account for in total energy consumption. Examples include: own electricity generation from hydropower or photovoltaics, heat generation from biomass or solar collectors. Other renewable energies are wind power or the use biogas and biofuels. Also heat pumps are using renewable energy, if they work an ambient heat sources.

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4.6 Traffic

Traffic is already a major energy consumer in many countries. In future, this sector is expected to display the greatest growth, which makes traffic the most significant quantity in terms of energy policy. For service companies, traffic is even today the largest energy consumer in and by the company. It includes four areas:

• goods and services supplied by the company (outgoing delivery and business trips)

Types of traffic

• internal company traffic at the particular location and between plants

• goods and services purchased by the company (ingoing delivery)

• staff traffic to and from work

Particularly staff traffic to and from work (home-work journeys) will be difficult to survey in the initial stages. Knowledge of staff traffic to work allows us to create incentives for using bicycles, public transport (rail, combined means of transport) or car pools. Information concerning staff travel to and from work should be collected in advance. A minimisation of costs and the duration of travel to and from work is of great interest to the company in order to increase staff satisfaction.

Reduction of traffic volume

Generally, it will not be possible to obtain the same data for deliveries to the company as for deliveries made by the company. However, the analysis of the available data should at least encourage the company to have local carrier services, for example, done by bicycle and to transport larger amounts of goods by rail.

4.7 Contracting

Many companies neglect energy aspects. Investments and planning are often not carried out until they have become unavoidable. However, as a result many potential savings and system renewals are not realised. A new instrument to solve this problem is contracting.

Use energy as a potential area of saving

4.7.1 What is contracting? Outside/ contractor financing

Contracting - or outside financing - means outsourcing energy supply or efficient energy utilisation measures to outside firms (contractors).

The user (=company) does not have any investment costs. Investments are funded by the difference between previous energy costs and new reduced energy costs. The contractor provides funding and takes care of handling.

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Textbook 4 - Energy analysis We distinguish between two types of contracting:

1. In plant contracting, the contractor pre-funds the plant and calculates his remuneration on the basis of the amounts of energy supplied to the user.

New plants or energy reduction measures

2. In energy-saving contracting, the outside firm (=contractor) implements measures aimed to reduce energy requirements. His remuneration is geared to the level of energy savings. (See diagram; source: Grazer Energieagentur)

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EinsparungSavings onEnergiekosteenergy costs

Investment Years

Contracting, then, allows a company to renew a piece of equipment (e.g. a heating system) and to implement energy-saving measures (e.g. building insulation or thermostatic valves) without the company having to put up the necessary funds by itself. In addition, the company receives professional support and service during the full duration of the contract.

Financing, support and service on the basis of contracting

Difference between contracting and leasing:

The last point mentioned also illustrates the fact that contracting is by no means equal to leasing. Unlike contracting, under a leasing contract a customer has to operate, maintain, insure and repair the machinery himself. He bears the full economic and technical risk of his investment.

4.7.2 When does contracting make sense?

Technical, organisational and financial reasons

• The existing energy supply system (e.g. heating system) is not state of the art.

• The company does not want to operate the machinery itself but rather wishes to outsource energy supply to an expert.

• The customer does not have a budget for the new heating system and other energy-saving measures.

• He wishes to cut energy costs and reduce pollution. • There is a mutual willingness to collaborate as partners for a longer

period.

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4.8 Drawing up an energy concept

Energy concept= current situation + any measurements + derivation of measures + evaluation and summary of measures

This information of recording the data forms the basis of and is also an integral part of any energy concept.

Only by evaluating the possible measures and assembling a set of measures it is possible to create a meaningful energy concept.

Often, it turns out while recording the energy situation that some essential data are missing. Then it is necessary for the company to either carry out detailed measurements or to have a service provider draw up an energy concept.

However, the more lucidly you have identified your energy situation yourself - and can thus estimate the basic possibilities - the better you will be able to adopt an external service or draw up the energy concept yourself.

The VDI (German Engineering Association) has drawn up a guideline (VDI 3922) for energy consulting in trade and industry and thus presented a possibility of creating an energy concept.

The following items must be observed:

1. Initial contact with consultant Steps in drawing up an energy concept (external consultants)

2. Quotation and commission (clarification of scope of services)

3. Identification of current situation

4. Performance of additional measurements (if data is inadequate) 5. Description and evaluation of current situation

6. Suggestions for rational use of energy

7. Development of an overall concept

8. Assessment and selection measures

9. Presentation and consultation report

10. Implementation and efficiency review

Current situation The description and evaluation of the current situation has been described previously. Once you have filled in all worksheets carefully, you will have a sound basis and good overall view of the energy situation in your company. For the energy concept, it makes sense to sum up the key items.

An investment decision often requires further detailed data and usually further measurements. With regard to electricity, for instance, such data are provided by the energy provider in the form of load development measurements. For questions of heat and refrigeration loss, thermography can be very helpful as an instrument of analysis. If such measurements need to be performed, it is usually necessary to consult professionals.

Additional measurements

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Textbook 4 - Energy analysis Suitable suggestions should be made on the basis of existing data and detailed measurements. Possible measures should consider:

Making suggestions

• Developing improvement strategies

• Identification of unnecessary energy consumption (distribution, consumers: e.g. buildings, idling times, steam consumers, ...)

• Reducing specific energy consumption (benchmarks)

• Optimising efficiency and utilisation rates (boiler optimisation, frequency converters, ....)

• Energy recovery

• Use of renewable energies

Above all with detailed measurements that are normally outsourced care should be taken that effective suggestions are drawn up and can be drawn up within the scope of an overall energy concept.

These numerous, diverse possibilities now have to be combined under an overall concept in the form of a report dealing with the key energy problems. The following should be particularly taken into account:

g and h: Conditions and criteria for a successful energy concept

• The preventive idea of CP must be observed. Production-integrated solutions and their extensive benefits must be described and not investments in end-of-pipe solutions

• Impact of measures on production (how does a measure influence energy, e.g. quality or sick leave) must be noted

• Observe combination of measures (e.g. water and energy consumption combined in process water, heat and electricity consumption on air-conditioning system)

• Payback periods of measures in the above sense must be detailed exhaustively (energy-saving investments often do not pay off if only energy is considered; however, energy does have a great influence on other areas. In addition, energy-saving measures are often infrastructural measures and thus often long-term)

Only when these points have been observed will detailed calls for tender make sense. Only in this way can you ensure that an investment will produce the desired benefit. When drawing up the concept, it should also be noted that the decision is generally taken by people with little knowledge of energy issues. By describing the overall benefit it is also more realistic that effective measures will be implemented.

Considering overall benefit

Finally, it should be mentioned that the worksheets in this dossier will be a great help when you review efficiency. By drawing up benchmarks and continuing to collect data through several years, you can monitor success by comparing data.

Efficiency review

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Textbook 4 - Energy analysis This collection of data will provide you with a good tool when you are dealing with suppliers. If a supplier is aware that you have detailed records and evaluations of energy-related data, he will be more careful and clearer in his quotations.

A successful energy concept is reflected in its implementation and balance (identification of all key energy aspects) By carefully filling in the worksheets you should be able to identify the key problems of your energy situation.

4.8.1 Thermography as an instrument of analysis

Measuring heat and refrigeration losses

Thermography is an instrument for evaluating heat and refrigeration losses. Depending on the design of the measuring apparatus you can measure surface temperatures* at specific points (with so-called infra-red thermometers) or visualise these temperatures with the aid of a thermal video camera.

* Strictly speaking, thermography does not measure temperatures but rather object radiation. However, due to reflections and different emission behaviours, non-experts should be very careful when

interpreting absolute temperatures.

0,0

100,0

200,0Thermal cameras for visualisation of the energy situation (colour coding)

In order to demonstrate the possibilities of thermographic measurements, we will give two examples: The first image shows a faulty pusher furnace. The temperature scale is indicated on the left of the picture. The colours/shades of grey on this scale correspond to the colours/shades of grey in the picture. The picture shows insulation faults (light patch on the right) and areas of poor door sealing (left of picture). Particularly, it is not possible to perceive the faults in the insulation (right) with the naked eye - i.e. on site - without the aid of thermography.

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Textbook 4 - Energy analysis The second picture also shows a thermal fault, this time in a prefab concrete element for a building facade. Of course, this fault cannot be detected with the naked eye either.

Min Max 8,7 11,5Min Max 8,7 11,5

*<4,6°C

5,0

6,0

7,0

8,0

9,0

10,0

11,0

12,0

13,0

*>13,4°C

The temperature scale has been indicated in both images so that this measurement allows at least a rough calculation of the losses involved. IR thermometers are also particularly useful when you wish to check temperature problems quickly. Although this only allows you to measure temperatures at specific points and does not provide any illustrative images to be saved for later use, this method is very inexpensive and is adequate for engineers. A major advantage of this method of camera analysis is, however, the “motivation thrust” given by this colourful visualisation of the company’s own energy situation. Particularly seen from this viewpoint, thermographic analysis is an ideal aid for conveying the CP idea and convincing staff of the necessity of measures.

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unido tool kit 4-textbook

Environment