K Energy Efficiency in Electrical Distribution

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Schneider Electric - Electrical installation guide 2010

K

SchneiderElectric-allrightsreserved

Chapter KEnergy eciencyin electrical distribution

Contents

Introduction K2

Energy eciency and electricity K3

2.1 An international appetite or regulation K3

2.2 NF EN 15232 standard K3

2.3 How to achieve energy eciency K3

Diagnosis through electrical measurement K6

3.1 Electrical measurements K6

3.2 Adapted measuring instruments K6

Energy saving opportunities K8

4.1 Motors K8

4.2 Speed variation K9

4.3 Control K11

4.4 Lighting K12

4.5 Power actor correction and harmonic ltering K14

4.6 Load management K15

4.7 Communication and inormation systems K16

4.8 Designing inormation and monitoring systems K19

How to evaluate energy savings K24

5.1 IPMVP and EVO procedures K24

5.2 Achieving sustainable perormance K26

2

3

4

5

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K - Energy eciency in electrical distribution

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Introduction

The aim o this chapter is to acilitate communication between the designers oelectrical installations and the energy consumers who use them. Consumers

requently require advice on how best to reduce consumption and the amount theyspend on energy.

While there are a number o actors infuencing attitudes and opinions towardsenergy eciency, particularly the increasing cost o energy and a growing awarenesso our responsibilities towards the environment, legislation probably has the greatestimpact on changing behaviour and practices. Various governments across the worldare setting themselves energy saving targets and passing regulations to ensurethese are met. Reducing greenhouse gas emissions is a global target set at theKyoto Earth Summit in 1997 and was nally ratied by 169 countries in December2006.

Under the Kyoto Protocol industrialised countries have agreed to reduce theircollective emissions o greenhouse gases by 5.2% compared to the year 1990between 2008 and 2012 (this represents a 29% reduction in terms o the emissionslevels expected or 2012 prior to the Protocol). One o Europes targets is a 20%reduction in or CO2 by 2020. Given that 27% o CO2 emissions originate romtransport, 16% rom residential buildings, 8% rom the service sector and 49% rom

industry proper, up to 50% o emissions can be attributed to electricity consumptionassociated with residential and commercial buildings. Moreover, as the use odomestic appliances and other equipment such as ventilation and air conditioningsystems increases, electricity consumption is rising at a aster rate than other ormso energy.

Against this background, the ollowing conditions will have to be satised in order toachieve a 20% reduction in consumption by 2020:

b All new buildings constructed must consume 50% less energy.

b 1 in 10 existing buildings must reduce consumption by 30% each year.

As ar as most countries are concerned, it is clear that 80% o the buildings whichwill be standing in 2020 have already been constructed. The reurbishment oexisting building stock and improving energy management is vital in meetingemission reduction targets. Given that in the western world, most buildings havealready undergone thermal perormance upgrades such as cavity wall insulation,lot insulation and double-glazing, the only potential or urther savings lies inreducing the amount o energy consumed. Action to improve the thermal and energy

perormance o existing buildings will almost certainly become compulsory in order tomeet the targets that have been set out.

Technology exists to help promote energy eciency on many levels, rom reducingelectricity consumption to managing other energy sources more eciently. Ambitiousregulatory measures may be required to ensure these technologies are adoptedquickly enough to achieve the 2020 targets.

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Energy saving regulations aect all buildings,both new and existing, as well as their electrical

installations.

2 Energy eciency andelectricity

2. Une rglementation volontariste partout dans le

mondeThe Kyoto Protocol saw governments start to set out clear commitments in terms oquantitative targets and specic agendas or reducing CO2 emissions.

In addition to their Kyoto obligations, many countries have set themselves xed,long-term targets in line with the latest EEIG (European Economic Interest Group)recommendations to the UNFCCC (United Nations Framework Convention onClimate Change) regarding energy saving and based on stabilising CO2 levels.

The European Union is setting a good example with its rm commitment, signedby all the national EU leaders in March 2007, to a 20% reduction by 2020. Knownas 3x20, this agreement aims to reduce CO2 emissions by 20%, improve energyeciency by 20% and increase the contribution made by renewable energies to 20%.Some European Countries are looking at a 50% reduction by 2050. Reaching thesetargets, however, wiII require signicant changes, with governments stepping up theiruse o regulations, legislation and standardisation.Across the world, legislation and regulations are serving to underline stakeholderobligations and put taxation and nancial structures in place.

b In the USA

v The Energy Policy Act o 2005,

v Construction regulations,

v Energy regulations (10CFR434),

v Energy management programmes or various states (10CFR420),

v Rules or energy conservation or consumer products (10CFR430).

b In China

v Energy conservation law,

v Architecture law (energy eciency and construction),

v lRenewable energy law,

v 1000 major energy conservation programmes or industry dans lUnion Europenne

b In the European Union

v The EU Emission Trading Scheme

v The Energy Perormance o Building Directive

v The Energy Using Product Directive

v The Energy End-use Eciency and Energy Services Directive.

2.2 see (Guide de linstallation lectrique)

2.3 How to achieve energy eciency

Whilst it is currently possible to obtain energy savings o up to 30%, this potentialreduction can only really be understood in terms o the dierences which existbetween active and passive orms o energy eciency.

Active and passive energy eciency

Passive energy eciency is achieved by such measures as reducing heat loss andusing equipment which requires little energy. Active energy eciency is achieved byputting in place an inrastructure or measuring, monitoring and controlling energyuse with a view to making lasting changes.

TIt is possible to build on the savings achieved here by perorming analyses andintroducing more suitable remedial measures. For example, although savings obetween 5% and 15% may be obtained by improving how installations are used orby optimising the equipment itsel (decommissioning redundant systems, adjustingmotors and heating), more signicant savings can also be achieved.

v Up to 40% on energy or motors by using control and automation mechanisms tomanage motorised systems,

v Up to 30% on lighting by introducing an automated management mechanismbased on optimal use.

It is important to remember, however, that savings may be lost through.

b Unplanned/unmanaged downtime aecting equipment and processes

b A lack o automation/adjustment mechanisms (motors, heating)

b A ailure to ensure energy saving measures are adopted at all times.

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Fig. K1 : Les 4 conditions de la prennit des conomies

Quantiying 2 Implementation o basic measures 3 Automatisation 4 Monitoring and improvement

b Kilowatt hour meters

b Energy quality meters

b Low-consumption devices

b Thermal insulation materials

b Energy quality

b Energy reliability

b Building management systems

b Lighting control systems

b Motor control systems

b Variable speed drives

b Home control systems

b Power management sotware

b Remote monitoring systems

Fig. K2: and monitoring technology ensures savings are sustained over the long term.

Energy

consumption

70 %

100 %

Time

Efficientdevices

andequipment

Usageoptimised

byautomation

Monitoring and support

b Up to 8% lost per year without a

monitoring and support programme

b Up to 12% lost per year without

systems for control and adjustment

A realistic approach would be to establish the identity o energy consumers andadopt passive ollowed by active saving measures, beore nally implementing

inspection and support devices to ensure that any savings made can be sustainedover the long term. This involves a our-stage process:

b The rst stage is concerned with diagnosis and primarily aims to get a better ideao where and how energy is being consumed. This requires the development oinitial measures and a comparative assessment process with a view to evaluatingperormance, dening the main areas or improvement and estimating achievableenergy saving levels. The logic behind this approach is based on the realisation thatyou can only improve what you can measure.

b The next stage involves establishing basic requirements in terms o passiveenergy eciency. These include:

v Replacing existing equipment/devices with low-consumption alternatives (bulbs,motors, etc.),

v Improving thermal insulation and ensuring that energy quality supports work in astable environment where savings can be sustained over time.

b The stage that ollows this involves automation and active energy eciency.Anything responsible or energy consumption must be subjected to a process o

active management aimed at achieving permanent savings.Active energy eciency does not require highly energy-ecient devices andequipment to be already installed, as the approach can be applied to all types oequipment. Good management is essential or maximum eciency there is nopoint in having low-consumption bulbs i you are going to waste energy by leavingthem switched on in empty rooms!

All things considered, energy management is the key to optimising use andeliminating waste.

b The nal stage consists o implementing basic changes, introducing automationand putting in place an inrastructure based around monitoring, support andcontinuous improvement. This inrastructure and the ongoing processes associatedwith it will underpin the pursuit o energy eciency over uture years (see Fig. K).

The key to sustainable savings

As Figure K2 illustrates, energy savings amounting to 30% are readily achievableas things stand, although annual losses o 8% must be expected i there is neitherproper support nor monitoring o key indicators. It is clear, thereore, that inormationis crucial to ensuring that energy savings are sustained over the long term.

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Fig. K3: Energy eciency solutions based on the lie cycle

Energy audit

and measurement

Industrial and

building processes

Low-consumption

devices, thermal

insulation, power

factor correction,

etc.

Adopt basic

measures

Passive energy

efficiency

Active energy efficiency

Optimisation via

adjustment andautomation

Variable speed drives,lighting/air conditioning

control, etc.

Monitor,

support,improve

Control,

improve

Installation of meters,monitoring devices,

energy saving analysis software

2 Energy eciency andelectricity

Consequently, energy monitoring and inormation systems are essential and must beput in place to deal with the challenges ahead.

Approaches to energy eciency must have a proper structure i signicant long-termsavings are to be achieved, but only those companies with sucient resources toactively intervene at any stage o a process will be in a position to pass the savingspromised on to their customers. This is where Schneider Electric can help with itsapproach based on managing the lie cycle o customer products (see Fig. K3).

Ultimately, the objectives set can only be achieved by sharing risks and developing awin-win relationship between those involved in the approach.

The reports provided by the energy monitoring or inormation systems can beused to ormulate suitable energy eciency projects in line with dierent strategiesacceptable to all those involved.

b Start with a simple project involving relatively little expense and geared towardsquick wins, beore going on to make more signicant investments (this is oten thepreerred business solution).

b Think in terms o how the investment or a project can and must be recouped whendevising a project (this is a popular method or assessing and selecting projects). Theadvantage o this method is the simplicity o the analysis involved. Its disadvantage is

the impossibility o tracking the ull impact o a project over the long term.

b Other, more complex strategies may be selected. These involve an analysis ovarious management parameters such as the current net value or the internalreturn-on-investment rate. Whilst the analysis required under these strategiesdemands more work, they provide a more precise indication o the overall impacto the project.

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3 Diagnosis through electricalmeasurement

3. Electrical measurements

Voltage and current, two key values or understanding (almost)everything

As ar as electrical measurements are concerned, voltage and current are the twovalues on which other values are based (power, energy, power actor, etc.).You should have a ull range o measuring devices capable o providing the specicmeasurements required or the application. You can signicantly increase the value oyour inormation by obtaining other data rom the same measurements:

b Operating positions or devices (start/stop, open/closed, etc.)

b Number o operating hours/switching operations

b Motor load

b Battery charge

b Equipment ailures

b etc.

There is no such thing as a one-size-ts-all solution. It is a question o nding thebest compromise, in technological and nancial terms, or the particular needs o the

given situation, whilst remembering that measurement accuracy involves costs whichhave to be compared against the anticipated returns on investment.

In addition, when the operators electrical network is expected to undergo requentchanges given the activities in which it is involved, these changes should prompt asearch or immediate and signicant optimisation measures.

Approaches to energy eciency also need to take other parameters into account(temperature, light, pressure, etc.), since, assuming energy is transormed withoutany losses, the energy consumed by a piece o equipment may exceed the useulenergy it produces. One example o this is a motor, which converts the energy itconsumes into heat as well as mechanical energy.

Collating relevant electrical data or specic objectives

As well as contributing towards energy eciency, the inormation gleaned romelectrical data is commonly used to support a number o other objectives:

b Increasing user understanding and providing opportunities or optimisingequipment and procedures

b Optimising unctionality and extending the service lie o equipment associated withthe electrical network

b Playing a pivotal role in increasing the productivity o associated processes(industrial or even administrative/management procedures) by avoiding/reducingperiods o lost productivity and guaranteeing the availability o a high-quality energysupply

3.2 Adapted measuring instruments

Electronic equipment is increasingly replacing analogue equipment in electricalinstallations. It supports more accurate measurement o new values and is able tomake these available to users at both local and remote locations.

All these various measuring devices (reerred to as PMD or PerormanceMeasuring and Monitoring Device) have to meet the requirements o international

standard IEC 61557-12. According to this standard, devices have a code denotingtheir installation options, operating temperature range and accuracy class.As a result, it has become signicantly easier to select and identiy thesedevices (see Fig. K4).

A number o devices have been designed or inclusion in this category. These includeSepam overload and measuring relays, TeSys U motor controllers, NRC 12 capacitorbattery controllers and Galaxy outage-ree supply devices. The new Masterpact andCompact circuit breakers with integrated Micrologic measuring devices (see Fig. K5)also simpliy matters by multiplying measurement points.

It is also now possible to broadcast measurements via digital networks. The tablein Figure K6 shows examples o measurements available via Modbus, RS485 orEthernet.

Fig. K4: Identiying measuring devices in accordance

with IEC 61557-12

c = Current measurement

S : with external sensor, D : direct measurement

v = Voltage measurement

S : avec capteur extrieur, D : mesure directe

Temperature class

Active energy accuracy class

PMD / cv / Ktt / p

Unit o measurement PM700 (Schneider Electric)

Code : PMD/SD/K55/

Fig. K5: Compact NSX circuit breaker equipped with a

Micrologic trip unit and TeSys U controller (Schneider Electric)

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3 Diagnosis through electricalmeasurement

Units omeasurement

MV measurementand overload relays

LV measurementand overload relays

Capacitor batterycontrollers

Monitoring andinsulation devices

Examples Circuit monitoringdevice, kilowatt hourmeter

Sepam Masterpact andCompact Micrologiccircuit breakers

Varlogic Vigilohm system

Control o energy consumption

Energy, inst., max., min. b b b b -

Energy, reclosing capability b b b - -

Power actor, inst. b b b - -

Cos inst. - - - b -

Improved energy availability

Current, inst., max., min., imbalance b b b b -

Current, wave orm capture b b b - -

Voltage, inst., max., min., imbalance b b b b -

Voltage, wave orm capture b b b - -

Device status b b b b -

Fault history b b b - -

Frequency, inst., max., min. b b b - -

THDu, THDi b b b b -

Improved electrical installation management

Load temperature, thermal state oload and device

b b - b -

Insulation resistance - - - - b

Motor controllers LV variable speed

drives

LV sot starters MV sot starters Outage-ree supply

devices

Examples TeSys U ATV.1 ATS.8 Motorpact RVSS Galaxy

Control o energy consumption

Energy, inst., max., min. - b - b b

Energy, reclosing capability - b b b -

Power actor, inst. - - b b b

Improved energy availability

Current, inst., max., min., imbalance b b b b b

Current, wave orm capture - - - b b

Device status b b b b b

Fault history b b b b -

THDu, THDi - b - - -

Improved electrical installation management

Load temperature, thermal state oload and device

b b b b b

Motor running hours - b b b -

Battery ollow up - - - - b

Fig. K6: Examples o measurements available via Modbus, RS485 or Ethernet

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K8



4 Energy saving opportunities

A number o dierent measures can be adopted to save energy (see Fig. K).

b Reduce energy use

These measures try to achieve the same results by consuming less (e.g. installinghighly energy-ecient lights which provide the same quality o light but consume lessenergy) or reduce energy consumption by taking care to use no more energy than isstrictly necessary (e.g. another method would be to have ewer lights in a room whichis too brightly lit).

b Save energy

These measures reduce costs per unit rather than reducing the total amount oenergy used. For example, day-time activities could be perormed at night to in orderto take advantage o cheaper rates. Similarly, work could be scheduled to avoid peakhours and demand response programmes.

b Energy reliabilityAs well as contributing to operational eciency by avoiding lost production, thesemeasures avoid the energy losses associated with requent restarts and the extrawork generated when batches o products go to waste.

Fig. K7: An overall strategy or energy management

Overall strategy forenergy management

Reduce

consumption

Optimise

energycosts

Improve

reliability andavailability

Everyone immediately thinks o equipment or transorming energy (motors, lighting/heating devices) when considering areas where savings can be made. Less obvious,perhaps, are the potential savings oered by the various control devices andprogrammes associated with this type o equipment.

4. Motors

Motorised systems are one o the potential areas where energy savings can be

made.Those wishing to improve passive energy eciency oten consider replacing motorsas a starting point. There are two reasons or this:

b To benet rom the advantages oered by new high-perormancemotors (see. Fig. K8),

b To rectiy oversizingMotors operating or long periods are obvious candidates or replacement byhigh-perormance motors, particularly i these existing motors are old and requirerewinding.Depending on the power they generate, high-perormance motors can improveoperational eciency by up to 10% compared to standard motors. Where motorshave undergone rewinding, eciency is reduced by 3% to 4% compared to theoriginal motor.

By contrast, replacement with high-perormance motors will not prove to be costeective i the existing standard-eciency motor particularly i it has not undergonerewinding experiences low or moderate levels o use (e.g. less than 30,000 hours

per year). It is also important to ensure that the new motors critical perormancecharacteristics (such as speed) are equivalent to those o the existing motor.

Fig. K8:Denition o energy eciency classes or LV motors

established by the European Commission and the European

Committee o Manuacturers o Electrical Machines and PowerElectronics (CEMEP)

95

90

85

80

75

701 15 90

Nominal value (kW)

Efficiency(%)

EFF 3EFF 2

EFF 14 poles

2 poles 2 & 4

poles

In industrial applications, motors account or60% o the energy consumed

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b As well as being inecient, oversized motors are more expensive to buy thancorrectly sized motors. Motors are at their most eective when operating at between

60% and 100% o their nominal load. Eciency reduces rapidly at loads below 50%.In the past, designers tended to develop oversized motors in order to provide anadequate saety margin and eliminate the risk o ailure, even in conditions whichwere highly unlikely to occur. Studies show that at least a third o motors are clearlyoversized and operate at below 50% o their nominal load. The average load or amotor is around 60%.

Larger motors also tend to have lower power actors, which can lead to chargesbeing levied or reactive power. When deciding whether to replace a motor, it isessential to take these actors, as well as the motors remaining lie cycle, intoconsideration. It is also important to remember that the expense o replacing anadmittedly oversized motor may not be justied i its load is very small or it is onlyused inrequently.

All things considered, every parameter needs to be taken into account beore makinga decision on replacing a motor.

Other approaches are also possible, as ar as motors are concerned:

b Improving active energy eciency by simply stopping motors when they no longer

need to be running. This method may require improvements to be made in terms oautomation, training or monitoring, and operator incentives may have to be oered.I an operator is not accountable or energy consumption, he/she may well orget tostop a motor at times when it is not required.

b Monitoring and correcting all the components within the drive chains, starting withthose on the larger motors capable o aecting overall eciency. This may involve,or example, aligning shats or couplings as required. An angular oset o 0.6 mm ina coupling can result in a power loss o as much as 8%.

b Paying special attention to pumps and ans, because:

v 63% o the energy used by motors is or fuid propulsion in components such aspumps and ans.

v Flow control oten uses valves, dampers and throttles, all o which cause energy tobe lost by blocking ducts whilst motors are operating at ull speed.

v Eective project planning can oten recoup investments in less than ten months.

4.2 Speed variation

A number o technologies can be used to vary fow or pressure within a system(see Fig. K). The technology chosen will depend on how the pump and an havebeen designed. For example, the pump used may be a displacement or centriugalpump, and the an used may be a centriugal or axial-fow an.

Fig. K9: Theoretical energy savings based on reducing an speed by hal

0

20

40

60

80

100

120

0 20 40 60 80 100 120

Q (%)

P (%)

Fixed speed

Variable speed

Savings can be made by sizing motors correctlyand using speed control and/or a variable

speed drive

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K0



Every time a an or a pump is installed with a view to achieving specic fow orpressure levels, sizing is based on maximum demand. As a result, oversizing is

the norm, and the device concerned will not operate eciently at other speeds.In general, systematic oversizing, combined with the ineective control methodsdescribed above, allows scope or signicant energy savings to be made by usingcontrol methods aimed at reducing the pump or ans supply current during periodso reduced demand.

Systems with ans and pumps are governed by certain correlations:

b Flow is proportional to shat speed, e.g. reducing speed by hal reduces fow by thesame amount (see Fig. K0).

Fig. K10: Relationship between energy and fow or dierent methods o an control (damper,inlet vanes and variable speed)

0

P (W)

Damper

Inlet guidevanes

Variable speed

0 Q (m3/s)

b Pressure or head is proportional to the square o the shat speed; halving the shatspeed reduces pressure by a quarter.

b Energy is proportional to the cube o the shat speed.Halving the shat speed reduces energy consumption by an eighth and, byimplication, halving the fow reduces energy consumption by an eighth.

In light o this, energy consumption can be reduced in cases where the an or thepump does not have to generate 100% o the fow or pressure. The savings involvedare signicant, even where the fow is only reduced by a small amount(see Fig. K). Unortunately, the eciency losses incurred by the variouscomponents mean that these theoretical values cannot be achieved in practice.

Technology Disadvantage

Control o stopping and starting This method is only eective when intermittent fow is acceptable.

Control valve: a valve is used to control fow by increasing rictional resistance atthe pumps outlet.

Energy is wasted, as the fow produced by the pump is subsequently reduced bythe action o the valve. In addition, pumps have an optimal operating level and

increasing resistance by this method may orce the pump to operate at a lessecient level (with additional energy loss) where it may be less reliable.

Bypass device: with this method, the pump turns continuously at ull speed andexcess fuid at the pumps outlet is channelled upstream, causing fow to be

reduced without the risk o outlet pressure increasing.

The system is very inecient, as the energy used to pump excess fuid iscompletely wasted.

Multiple pumps or ans: these congurations support ad hoc increases by

activating extra pumps or ans, making control dicult.

There is usually a loss in eciency, as the actual need is oten somewhere

between the dierent speeds available.

Damper: a similar technology to the control valve in systems with a pump, this

reduces fow by partly obstructing the ans outlet.

Energy is wasted, as the fow generated by the an is subsequently reduced by

the action o the damper.

Overfow valve: a similar technology to the bypass valve in systems with a pump.The an rotates at ull speed continuously and the excess gas fow is evacuated.

The system is very inecient, as the energy used to propel the air or gas iscompletely wasted.

Fan with adjustable blades: the fow can be changed by adjusting the blades. Energy is wasted, as the fow generated by the an is subsequently reduced bythe action o the blades.

Inlet guide blades: ns are used to obstruct or acilitate gas fow inside a an,thereby determining its eciency.

The an does not generate excess fow, but does not operate at maximumeciency either.

Fig. K11 : Examples o technologies which may benet rom using a variable speed drive

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Using a variable speed drive (see Fig. K12), as opposed to the technologies

discussed earlier, constitutes an active energy eciency method and provides the

type o variable eciency required or optimal pump or an operation.

Altivar 12 (< 4 kW ) Altivar 21 (< 75 kW) Altivar 71 (< 630 kW)

Fig. K12: Altivar drives with dierent power ratings

Certain scenarios avour simple solutions:

b When changing the dimensions o the pulleys enables ans or pumps to turnat their optimal speed. This solution does not aord the fexibility associated withvariable speed drives, but it involves little work and could well be covered by themaintenance budget without the need or any additional investment.

b When the an or pump can operate at ull speed continuously without the controleatures reerred to above being installed, or with these control eatures installed butunused (e.g. with dampers and valves ully opened). Under this arrangement, thedevice will operate at or near optimum eciency.

In reality, the potential savings will depend on the model o the an or pump used,its intrinsic eciency, the size o the motor, annual operating hours and the cost o

electricity locally. These savings can be calculated using special sotware or can beestimated with some accuracy by installing temporary meters and analysing the dataobtained.

4.3. Control

The previous section showed how pumps and ans can benet rom the use ovariable speed drives. Still urther advantages can be enjoyed by using these inconjunction with control devices tailored to meet individual requirements.

b Control based on xed pressure and variable fow: this type o control is oten usedor water distribution systems (drinking water, irrigation). It is also used to circulatefuids in cooling applications.

b Control or heating systems: in heating and cooling circuits, fow should vary withtemperature.

b Control based on xed fow and variable pressure: mainly associated with pumping

applications (pressure dierences caused by dierent levels) such as cleaning,watering, cooling and reezing installations. These require a certain amount o water,even where suction and discharge conditions vary.The immediate advantages are:

b Improved control and greater accuracy in terms o pressure and fow values

b Signicant reduction o transient eects within the electrical network and omechanical restrictions aecting systems

b Reduced noise and vibrations, as drives support ne speed adjustments, therebypreventing equipment rom operating at the resonance requency or ducts and pipesb Smooth starting and stopping

These in turn bring about urther advantages:

b Greater reliability and extended service lives or systemsb Simpler tubing and pipe systems (by dispensing with dampers, control valves andbypass pipes)

b Reduced maintenance

The ultimate goal is to reduce energy consumption and its associated costs.


Speed regulation: Correctly adjusting energy

consumption in line with needs

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K2



4.4. Lighting

Lighting can account or over 35% o energy consumption in buildings, depending onthe types o activities carried out in them. Lighting control is one o the easiest waysto make substantial energy savings or very little investment and is one o the mostcommon energy saving measures.

Lighting systems or commercial buildings are governed by standards, regulationsand building codes. Lighting not only needs to be unctional, but must also meetoccupational health and saety requirements and be t or purpose.

In many cases oce lighting is excessive and there is considerable scope or makingpassive energy savings. These can be achieved by replacing inecient luminaires,by replacing obsolete lights with high-perormance/low-consumption alternatives andby installing electronic ballasts. These kinds o approach are especially appropriatein areas where lighting is required constantly or or long periods and savings cannotbe achieved by simply switching lights o. The time taken to recoup investmentsvaries rom case to case, but many projects require a period o around two years.

Lights and electronic ballasts

More ecient lights may be a possibility, depending on the needs, type and age othe lighting system. For example, new fuorescent lights are now available, althoughballasts also need to be replaced when lights are changed.New types o ballast are also available, oering signicant energy savings comparedto the earlier electromagnetic ballasts. For example, T8 lights with electronic ballastsuse between 32% and 40% less electricity than T12 lights tted with electromagneticballasts.Having said this, electronic ballasts do have a number o disadvantages comparedwith magnetic ballasts. Their operating requency (between 20,000 and 60,000 Hz)can introduce harmonic noise or distortion into the electrical network and presentsthe risk o overheating or reducing the service lie o transormers, motors andneutral lines. There is even a danger o overvoltage trips being deactivated andelectronic components sustaining damage. However, these problems are mainlyrestricted to acilities with heavy lighting loads and a large number o electronicballasts. Most current types o electronic ballast eature passive ltering in order tokeep harmonic distortion to less than 20 percent o undamental current, or even 5%

or more sensitive acilities (hospitals, sensitive manuacturing environments, and soon).

Other types o lighting may be more appropriate, depending on the conditionsinvolved. An assessment o lighting needs will ocus on evaluating the activitiesperormed and the required levels o illumination and colour rendering. Many existinglighting systems were designed to provide more light than required. Designing a newsystem to closely t lighting needs makes it easier to calculate and ultimately achievesavings.

Apart rom the issue o savings, and without orgetting the importance o complyingwith the relevant standards and regulations, there are other advantages associatedwith retrotting lighting systems. These include lower maintenance costs, the chanceto make adjustments based on needs (oce areas, walk-through areas etc.),greater visual comort (by eradicating the requency beat and fickering typicallyassociated with migraine and eye strain) and improved colour rendering.

Refectors

A less common passive energy eciency measure, but one which is worthconsidering in tandem with the use o lights tted with ballasts, is to replace therefectors diverting light to areas where it is needed. Advances in materials anddesign have resulted in better quality refectors which can be tted to existing lights.These refectors intensiy useul light, so that ewer lights may be required in somecases. Energy can be saved without having to compromise on lighting quality.New, high-perormance refectors oer a spectral eciency o over 90%(see Fig. K3). This means:

b Two lights can be replaced by a single light, with potential savings o 50% or morein terms o the energy costs associated with lighting.

b Existing luminaires can be retrotted by installing mirror-type refectors withouthaving to adjust the distance between them. This has the advantage o simpliyingthe retrotting process and reducing the work involved, with minimal changes madeto the existing ceiling design.

+ +

Above:Around 70% of a fluorescent tubes

light is directed sideways and upwards.

Below:The new silver surfaces are designed to reflect

the maximum amount of light downwards.

+

Fig. K13: Illustration o the general operating principle or high-perormance refectors

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K3



Lighting control

The passive energy saving measures described above leave urther scope or

making savings. The aim o lighting control programmes is to give users the requiredlevels o convenience and fexibility, whilst supporting active energy savings and costreduction by switching lights o as soon as they are no longer needed. There are anumber o technologies available with various degrees o sophistication, althoughthe time taken to recoup investments is generally short at six to twelve months. Amultitude o dierent devices are currently available too (see Fig. K4).

Fig. K14: A selection o lighting control devices: timers, light sensors, movement sensors

b Timers to turn o lights ater a certain period has passed. These are best used inareas where the typical time spent or period o activity is clearly dened (such ascorridors).

b Occupancy/movement sensors to turn o lights when no movement has beendetected or a certain period. These are particularly well suited to areas wherethe time spent or period o activity cannot be accurately predicted (storerooms,stairwells, etc.).b Photoelectric cells/daylight harvesting sensors to control lights near windows.When sucient daylight is available, lights are turned o or switched to night-lightmode.

b Programmable clocks to switch lights on and o at predetermined times (shopronts, oce lights at nights and weekends)

b Dimmable lights to provide a low level o illumination (night light) at o-peakperiods (e.g. a car park requiring ull illumination until midnight, but where lowerlevels will suce between midnight and dawn)

b Voltage regulators, ballasts or special electronic devices to optimise energyconsumption or lights (fuorescent tubes, high-pressure sodium lights, etc.)

b Wireless remote control devices or simple and economical retrotting o existingapplications

These various technologies may be combined and can also be used to create aspecic eect or atmosphere. For example, programmable lighting panels in meetingareas (or board meetings, presentations, conerences, etc.) have a number odierent light settings which can be changed at the fick o a switch.


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K4



Centralised lighting management

Some o the lighting control systems currently available, such as those based on the

KNX protocol, have the additional advantage o supporting integration into buildingmanagement systems (see Fig. K5).They oer greater fexibility o management and centralised monitoring, and providemore scope or energy savings by enabling lighting controls to be integrated intoother systems (e.g. air conditioning). Certain systems enable energy savings o 30%,although eciency levels will depend on the application involved and this must bechosen with some care.

Fig. K15: An example o links established using Schneider Electrics KNX system

I this type o system is to produce results, the design and implementation stagemust begin with an audit o energy consumption and a study o the lighting systemwith a view to devising the best lighting solution and identiying potential reductionsin terms o both costs and energy consumption. As ar as this kind o technologyis concerned, Schneider Electric also has solutions or oces as well as exteriorlighting, car parking acilities, parks and landscaped gardens.

4.5 Power actor correction and harmonic ltering

b I the energy distribution company imposes penalties or reactive powerconsumption, improving power actor correction is a typically passive energy savingmeasure. It takes immediate eect ater implementation and does not require anychanges to procedures or sta behaviour. The investment involved can be recoupedin less than a year.

See Chapter L or ur ther details.

b Many types o equipment (variable speed drives, electronic ballasts, etc.) andcomputers generate harmonics within their line supply. The eects produced cansometimes be signicant (transient overvoltages causing protection relays to trip,or heat and vibration potentially reducing the eciency and service lie o suchequipment as capacitor banks used or power actor correction). Harmonic ltering isanother typical passive energy saving measure to consider.See Chapter M or urther details.

Touch panel

Control station

Binary input

module External movement

sensor

KNX bus

Trancent

pushbutton

Internal

movement sensor

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K5




4.6 Load management

As part o their drive towards synchronizing the consumption and production oelectrical energy over the long term, energy distribution companies tailor their ratesto encourage consumers to reduce their requirements during peak periods.

A number o dierent strategies are possible, depending on consumption levels andoperating requirements: restricting demand (see Fig. K6), avoiding peak periods,load scheduling or even generating additional energy on site.

Fig. K16: An example o a load-management strategy

kW

Time

Reduced peakdemand

Peak demand

Peak demand rescheduledto keep it below a giventhreshold

b Demand restrictionEnergy distribution companies can use this solution in supply contracts containingoptional or emergency (involving compulsory limits) restrictive clauses whoseapplication is determined by the consumer (based on special rates). Thismanagement policy is typically used during the hottest or coldest months o theyear when companies and private customers have very high requirements orventilation, air conditioning and heating, and when electricity consumption exceedsnormal demand considerably. Reducing consumption in this way can proveproblematic in residential and service sector environments, as they may considerablyinconvenience building occupants. Customers rom industry may show more o aninterest in this type o scheme and could benet rom contracts reducing unit costsby up to 30% i they have a high number o non-essential loads.

b Peak demand avoidanceThis method involves moving consumption peaks in line with the dierent ratesavailable. The idea is to reduce bills, even i overall consumption remains the same

b Load schedulingThis management strategy is an option or companies able to benet rom lowerrates by scheduling consumption or all their processes where time o day is neitherimportant nor critical.

b Additional energy generation on siteThe use o generating sets to supply energy improves operational fexibility byproviding the energy needed to continue normal operations during periods o peak

or restricted demand. An automated control system can be congured to managethis energy production in line with needs and the rates applicable at any giventime. When energy supplied rom outside becomes more expensive than energygenerated internally, the control system automatically switches between the two.

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K6



4.. Communication and inormation systems

Inormation systems

Whether it relates to measurements, operating statuses or rate bases, raw data canonly be useul when converted into usable inormation and distributed on a need-to-know basis to all those involved in energy eciency with a view to improving theexpertise o all participants in the energy management process. Data must alsobe explained, as people can only develop the management and intervention skillsintegral to any eective energy saving policy i they ully understand the issuesinvolved. Data distribution must produce actions, and these actions will have tocontinue i energy eciency is to be sustained (see Fig. K).However, this cycle o operations requires an eective communication network to bein place.

Fig. K17:Operating cycle or data essential to energy eciency

Data analysis(raw data converted

into usable information)

Action

(understanding

aiding results)

Communication

(information

aiding understanding)

Data gathering

The inormation system can then be used on a daily basis by the operators at thevarious locations where electricity is consumed (or industrial processes, lighting,air conditioning, and so on) to achieve the energy eciency objectives specied bycompany management. It can also ensure these same locations make a positivecontribution to company operations (in terms o product volumes, conditions orsupermarket shoppers, temperatures in cold rooms, etc.).

Monitoring systems

b For quick audits which can be perormed on an ongoing basis.Encouraging amiliarity with data and distributing it can help keep everything up todate, but electrical networks develop rapidly and are permanently raising questionsabout their ability to cope with such new developments.With this in mind, a system or monitoring the transer and consumption o energy isable to provide all the inormation needed to carry out a ull audit o the site. As well

as electricity, this audit would cover water, air, gas and steam.Measurements, comparative analyses and standardised energy consumption datacan be used to determine the eciency o processes and industrial installations.b For rapid, inormed decision makingSuitable action plans can be implemented. These include control and automationsystems or lighting and buildings, variable speed drives, process automation, etc.Recording inormation on eective equipment use makes it possible to determineaccurately the available capacity on the network or a transormer and to establishhow and when maintenance work should be perormed (ensuring measures aretaken neither too soon nor too late).

Communication networks

Inormation and monitoring systems are synonymous with both intranet and Internetcommunication networks, with exchanges taking place within computer architecturesdesigned on a user-specic basis.

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K



b IntranetFor the most part, data exchange in the industrial sector uses Web technologies

permanently installed on the companys communications network, typically anintranet network or the sole use o the operator.As ar as industrial data exchange between systems connected via a physicaltransmission link, such as RS485 and modem (GSM, radio, etc.), is concerned,the Modbus protocol is very widely used with metering and protection devices orelectrical networks. Initially created by Schneider Electric, this is now a standardprotocol.

In practice, electrical data is recorded on industrial Web servers installed inenclosures. The popular TCP/IP standard protocol is used or transmitting this datain order to reduce the ongoing maintenance costs associated with any computernetwork. This same principle is used by Schneider Electric to communicate dataassociated with promoting energy eciency. No additional sotware is needed aPC with an Internet browser is all that is required. The act that enclosures areautonomous removes the need or an additional computer system. As such, allenergy eciency data is recorded and can be communicated in the usual manner viaintranet networks, GSM, xed telephony, etc

b Internet

Remote monitoring and control improve data availability and accessibility, whilstoering greater fexibility in terms o servicing. Figure K18 shows a diagram o thistype o installation. Connection to a server and a standard Web browser makes itmuch easier to use data and export it to Microsot Excel spreadsheets or thepurpose o tracing power curves in real time.

Fig. K18:Example o an intranet inormation network protected by a server(EGX400 Schneider Electric) and monitored rom the Internet network

PM710powermeters

PM850powermeters

Modbusserial link

Company

HTML server

Intranet

Internet

http://

http://

b ArchitecturesHistorically and or many years, monitoring and control systems were centralised andbased on SCADA automation systems (Supervisory Control And Data Acquisition).

These days, a distinction is made between three architecture levels (see Fig. onthe next page).

v Level 1 architecture

Thanks to the new capabilities associated with Web technology, recent timeshave witnessed the development o a new concept or intelligent equipment. Thisequipment can be used at a basic level within the range o monitoring systems,oering access to inormation on electricity throughout the site. Internet access canalso be arranged or all services outside the site.


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K8




This system has been specically designed or electricians and adapted to meet the

demands o electrical networks.This architecture is based on a centralised monitoring system designed to satisyall the monitoring requirements or the electrical network. As might be expected,installation and maintenance work requires less expertise than or Level 3, since allthe electrical distribution devices are already contained in a specialised library. Inaddition, acquisition costs can be kept to a minimum, as there are ew requirementsin terms o system integration.

Level 2 and Level 3 can be used side by side at certain sites.


Investment in this type o system is usually restricted to top-o-the-range acilitiesconsuming large amounts o energy or using equipment which is highly sensitive tovariations in energy quality and has high demands in terms o electricity availability.To ensure these high demands or availability are met, the system oten requiresresponsibility to be taken or installation components as soon as the rst aultoccurs. This should be done in a transparent manner (any impact should be clear).In view o the substantial ront-end costs, the expertise required to implement the

system correctly and the update costs generated as the network develops, potentialinvestors may be deterred and they may require highly detailed prior analyses to beconducted.

Power Logic

ION Entreprisespecialised

monitoringsystems

Standard

Web browser

1

2

3

Intelligentenergy

managementequipment

Other services

Equipment

server

Energymanagement

equipment

Equipment

gateway

Energy

managementequipment

Other

services

ProcessEquipmentgateway

Generalsitemonitoring

Specialisednetwork

monitoring

Function

levels

Basicmonitoring

Standard network Vulnerable electrical networks Top-of-the-range sitesSystemcomplexity

General

monitoringsystem

Fig. K19: Layout o a monitoring system

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K



4.8 Designing inormation and monitoring systems

In reality, systems or monitoring and energy control are physically very similar andoverlap with the electrical distribution architecture whose layout they oten replicate.The arrangements shown in Figure K20 to Figure K24 represent possible examplesand refect the requirements typically associated with the distribution involved(in terms o eeder numbers, the amount and quality o energy required, digitalnetworks, management mode, etc.). They help to visualise and explain all the variousservices which can be used to promote energy eciency.

Fig. K20: Monitoring architecture or a small site which only supports sub-metering


Receiverfeeder

Powerincomer

Micrologic ECompact NSX 63to 630 A circuitbreaker

Main LV distribution board

Modbus - RS485

Installation monitoring(PowerView software on PC)

Modbus TCP/IPEGX100 gateway

Heating/airconditioning feeder

PM9Cpower meters

Lightingfeeder

Unmonitoredfeeders

(sockets, etc.)

Secondaryfeeder which

has been shed

Load-sheddingcontactor

IntranetModbus - Ethernet TCP/IP

http://

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K20



Fig. K22: Architecture or large multiple-site arrangements

Monitoring andcontrol (PC browser)

Sites energymanagement system:ION Entreprise

Companys energymanagement system:ION EEM

Buildings andautomation

systems

Large industrial site 1

Intranet


Sites energymanagement system:ION Entreprise

Large industrial site 2

Monitoringand control(PC browser)

Intranet

Other dataresources

relating to energy

Distributordata

sources

Managementsystems

(EAM, ERP)

Intranet

http://

http://http://

Receiverfeeder

Powerincomer

Main LV distribution

board for site A

Monitoring andcontrol of sitesA and B (PC browser)

EGX400Web server

EGX400Web server

Heating/airconditioning

feeder

PM9Cpower meters

Lightingfeeder

Unmonitoredfeeders

(sockets, etc.)

Secondaryfeeder

which hasbeen shed

Receiverfeeder

Heating/airconditioning

feeder

Lightingfeeder

Unmonitoredfeeders

(sockets, etc.)

Secondaryfeeder

which hasbeen shed


InternetEthernet TCP/IP

Powerincomer

Main LV distribution

board for site B

Monitoring andcontrol of sitesA and B (PC browser)

PM9Cpower meters Load-shedding

contactor

Optional centralised

PowerView monitoring

Compact NSXwith Micrologic controland measurement unit

http:// http://

Compact NSX withMicrologic controland measurement unit

Fig. K21 : Monitoring and control architecture or a company with several small sites

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K2




Fig. K23: Monitoring and control architecture or a large, sensitive industrial site

ION 7850powermeterMasterpact

Meters

Water

Gas

Powerincomer

Compact NSXcircuit breakers

withMicrologic E

Compact NScircuit breaker

withMicrologic P

Main LVdistributionboard

Main high energy

availabilitydistribution board

Feeders which have been shed



PM9Cpowermeter

Remote controlCompact NSX sourcechangeover system

Automation

Ethernet TCP/IP

Modbus - RS485

image

??


GE

ION Entreprise

centralised monitoring+ Web server

Intranet

=

~

=

~

Inverterand bypass

Micrologic ECompact NSX63 to 630 Acircuit breakers

Sensitive feeders and term for service continuity and availability.- Preventive/predictive/strategic maintenance- Measurement of electrical parameters with harmonicanalyses and diagnostics

ModbusEthernetEGX100gateway

Micrologic ECompactNSX circuitbreakers

Secondary distribution board

Modbus - RS485

ModbusEthernetEGX100 gateway

Sub-meteringand monitoring

Sub-meteringonly

Feeders with no preventivemaintenance or below 63 A,

but to be included in sub-metering

Small feederswithout

sub-metering

Secondaryfeeder

which hasbeen shed

Load sheddingfor consumption

peaks withsub-metering

and monitoring

Major feeders forcontrolling big consumers

Load-shedding

contactor

PM9Cpower meter

Concentrator

ME3ZRkilowatthour meter

EN40kilowatthour meter

http://

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K22



Fig. K24: Architecture or a large service-industry site

PM850powermeter

CVC controller andWeb server load shedding,

Xenta 731 Modbus-Ethernet gateway

CVC controller andWeb server

load shedding,Xenta 731

Modbus-Ethernetgateway

Meters

ater

Gas

Powerincomer

Compact NSXcircuit breakers

withMicrologic E

Main LV distribution board


Feeders which

have been shed

Sub-meteringand monitoring

Sub-metering only


PM9Cpowermeter

PM9C powermeter

Lightingfeeder

CVC feeder(fan coil units)

Lightingfeeder

CVC feeder(fan coil units)

PM9C powermeter

PM9Cpowermeter

Lan Talk - Ethernet TCP/IP

Modbus - RS485

Lan Talk-FTT-10

Modbus - RS485

Monitoringand control

(PC browser)

VISTA centralisedmonitoring

Unmonitoredfeeders

(sockets, etc.)

Unmonitoredfeeders

(sockets, etc.)

Intranet


Sub-metering only

PM9Cpowermeter

ME3ZRkilowatt

hourmeter



Masterpact

ME3ZRkilowatt

hour meter


Xenta 411or 421 logicinput module

Xenta 411or 421 logic

input module

http://

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K23




In addition, these diagrams make it clear that the choice o components isdetermined by the choice o architecture (or example, the sensors must be right

or the digital bus). The reverse also applies, however, since the initial choice oarchitecture may be aected by a technological/economic assessment o componentinstallation and the results sought. In act, the cost (in terms o purchase andinstallation) o these components, which sometimes have the same name butdierent characteristics, may vary widely and produce very variable results:

b A measuring device can measure one or more parameters with or without usingcalculations (energy, power, cos ).

b Replacing a standard circuit breaker with a circuit breaker containing an electroniccontrol unit can provide a great deal o inormation on a digital bus (eective andinstantaneous measurements o currents, phase-to-neutral and phase-to-phasevoltages, imbalances o phase currents and phase-to-phase voltages, requency,total or phase-specic active and reactive power, etc.).When designing these systems, thereore, it is very important to dene objectives orenergy eciency and be amiliar with all the technological solutions, including theirrespective advantages, disadvantages and any restrictions aecting their application(see Fig. K2).To cover all the various scenarios, it may be necessary to search through various

hardware catalogues or simply consult a manuacturer oering a wide range oelectrical distribution equipment and inormation systems. Certain manuacturers,including Schneider Electric, oer advisory and research services to assist thoselooking to select and implement all these various pieces o equipment.

Energy savings Cost optimisation Availabil ity andreliability

Variable speed drivesp p p p p

High-perormancemotors and transormers

p p p

Supply or MV motorsp p p

Power actor correctionp p p p

Harmonics managementp p p p

Circuit congurationp p p

Auxiliary generatorsp p p p p

Outage-ree supplydevices (see page N)

p p p

Smooth startingp p p p p

iMCCp p p p

Architecture based onintelligent equipment

Level p p p

Specialised, centralised

architecture orelectricians

Level 2

p p p p p p

General/conventional,centralised architecture

Level 3p p p p p p

Fig. K27: Solutions chart

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K24



5 How to evaluate energy savings

One o the main obstacles acing those interested in devising and implementingenergy eciency projects is the lack o reliable nancial data to provide a convincing

business case. The higher the investment, the greater the need or credible proo othe proposed advantages. As such, it is very important to have reliable methods orquantiying results when investing in energy eciency.

5. IPMVP and EVO procedures

To cater or this need, EVO (Eciency Evaluation Organization), the bodyresponsible or evaluating perormance, has published the IPMVP (InternationalPerormance Measurement and Verication Protocol). This guide describes theprocedures used when measuring, calculating and documenting the savingsachieved as a result o various energy eciency projects. So ar, EVO haspublished three volumes o the IPMVP, the rst o which, Concepts and Optionsor Determining Energy and Water Savings, outlines methods o varying cost andaccuracy or establishing total savings made or those made solely in terms o energyeciency. Schneider Electric uses this document when putting together energy

eciency projects.

IPMVP principles and eatures

Beore implementing the energy eciency solution, a study based on IPMVPprinciples should be carried out over a specic period in order to dene therelationship which exists between energy use and operating conditions. During thisperiod, reerence values are dened by taking direct measurements or by simplystudying the energy bills or the site.Ater implementation, this reerence data is used to estimate the amount o energy,reerred to as adjusted-baseline energy, which would have been consumed hadthe solution not been implemented. The energy saved is the dierence between thisadjusted-baseline energy and the energy which was actually measured.

I a verication and measurement plan is put together as part o an IPMVPprogramme, it needs to be:

b Accurate

Verication and measurement reports should be as accurate as possible or the

budget available. The costs involved in verication and measurement should normallybe comparatively low in terms o the anticipated savings.b CompleteThe study o energy savings should refect the ull impact o the project.

b ConservativeWhere doubts exist in terms o results, verication and measurement proceduresshould underestimate the savings being considered.

b ConsistentThe energy eciency report should cover the ollowing actors in a consistentmanner:

v The various types o energy eciency projectv The various types o experts involved in each project

v The various periods involved in each project

v The energy eciency projects and the new energy supply projects

b RelevantIdentiying savings must involve measuring perormance parameters which are

relevant or less well known, with estimates being made or less critical or morepredictable parameters.

b Transparent

All the measurements involved in the verication and measurement plan must bepresented in a clear and detailed manner.

The inormation provided in this chapter istaken rom Volume 1 o the IPMVP guide

published by EVO (see www.evo-world.org)

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K25



IPMVP options

Four study levels or options have been dened in line with the objectives assigned

to this energy eciency approach:b Retrotting isolation systems with measurements o all key parameters = Option A

b Retrotting isolation systems with measurements o all parameters = Option B

b Whole acility = Option C

b Calibrated simulation = Option DFigure 28 sets out these options in a table. The algorithm in Figure 2 shows theprocess o selecting options or a project.

Option A Option B Option C Option D

Financial objective Retrot isolation systems: key

parameter measurement

Retrot isolation systems: all

parameter measurement

Whole acility Calibrated simulation

Description Savings are calculatedusing data rom the mainperormance parameter(s)

dening energy consumptionor the system involved in the

energy eciency solution.Estimates are used or

parameters not chosen oractual measurements.

Savings are calculated usingactual energy consumptiondata or the system involved in

the energy eciency solution.

Savings are established usingactual energy consumptiondata or the acility or a section

o it. Data or energy usewithin the acility as a whole

is gathered on an ongoingbasis throughout the reporting

period.

Savings are established bysimulating energy consumptionor the acility or a section o it.

There must be evidence thatthe simulation procedures are

providing an adequate modelo the acilitys actual energy

perormance.

Savings calculation An engineering calculationis perormed or the energyconsumed during the baseline

period and the reporting periodbased on:

b Ongoing or short-termmeasurements o the main

perormance parameter(s),

b And estimated values.

Ongoing or short-termmeasurements o the energyconsumed during the baseline

period and the reporting period

An analysis o data on theenergy consumed duringthe baseline period and the

reporting period or the wholeacility. Routine adjustments

are required, using techniquessuch as simple comparison or

regression analysis.

Energy use simulation,

calibrated with hourly or

monthly utility billing data

When to use option On the one hand, the resultsobtained using this optionare rather equivocal given

that some parameters areestimated. Having said this,

it is a much less expensivemethod than Option B.

Option B is more expensivethan Option A, as allparameters are measured. It is

the better option, however, orcustomers who require a high

level o accuracy.

For complex energymanagement programmesaecting many systems within

a acility, Option C supportssavings and helps to simpliy

the processes involved.

Option D is only used whenthere is no baseline dataavailable. This may be the

case where a site did not havea meter beore the solution

was implemented or whereacquiring baseline data would

involve too much time orexpense.

Fig. K28: Summary o IPMVP options


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K26



Start

Measurementof on-site

factors or ECMperformance

Facility performanceECM performance

No

No

No

No

No

Yes

Yes

Yes

Yes

Yes

No

Yes

Able to isolateECM with meter(s)?

Need proofof full performance?

Install isolationmeters for all

parameters andassess interactive

effects.

Install isolation meters for

key parameters, assessinteractive effects andestimate well known

parameters.

Need to assesseach ECMseparately?

Analysis ofmain meter data

Simulatesystemor facility.

Obtaincalibration

data

Calibratesimulation.

Simulate withand without

ECM(s).Donnes derfrence ou donnes

de la priode documentemanquantes ?

Missing baselineor reporting

period data?

Option BRetrofit isolation:

measurement ofall parameters

Option ARetrofit isolation:

measurementof key parameters

Option CWhole facility

Option DCalibratedsimulation

Expectedsavings >10%?

Fig. K29: Process or selecting an IPMVP option or a project

Energy performance curve

Energyconservation

measures

Contactwith

supportservices

Savings with ongoing services

Savings without proper maintenance

Energyaudit andconsulting

Fig. K30: Ensuring perormance is sustainable over time

5.2. Achieving sustainable perormanceOnce the energy audits have been completed, the energy saving measures havebeen implemented and the savings have been quantied, it is essential to ollow theprocedures below to ensure perormance can be sustained over time. Perormancetends to deteriorate if there is no continuous improvement cycle in place (see Fig. K30).

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K2



A continuous improvement cycle will only work i there is an energy monitoringsystem in place, and this system is used eectively and maintained. The system

supports a continuous and proactive analysis o energy use at the site, and inormsrecommendations or improving the electrical distribution system.

Support services, either on site or at a remote location (accessible via telephone,e-mail, VPN (Virtual Private Network) or any other type o long-distance connection),are oten required to ensure optimal perormance or this type o system and the bestuse o the collected data. Thanks to their contribution in terms o experience andavailability, these services also complement the operators in-house services. Theservices available may include:

b Monitoring the perormance o measuring devices

b Updating and adapting sotware

b Managing databases (e.g. archives)b Continuously adapting the monitoring system in line with changing controlrequirements.


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Documents

K Energy Efficiency in Electrical Distribution