benefiting from energy conservation in retail establishments

BENEFITING FROM ENERGY CONSERVATION

IN RETAIL ESTABLISHMENTS

Global Energy Challenges Eradicating Energy Poverty Mobilizing Capital for Energy Infrastructure Achieving Energy Security Achieving Energy Sustainability and

Climate Stability

Energizing Development The provision of energy services is a vital

precursor to economic development

0

5000

10000

15000

20000

25000

30000

0.250 0.350 0.450 0.550 0.650 0.750 0.850 0.950

Human Development Index (HDI)

Ele

ctri

cty

Co

nsu

mp

tio

n p

er C

apit

a (k

ilo

wat

t-h

ou

rs)

UNDP, Human Development Index

M a p o f G lo ba l E ne rgy P o ve rtyM a p o f G lo ba l E ne rgy P o ve rty

1.6 b illion people have no access to electricity, 80% of them in South A sia and sub-Saharan A frica

N e t O i l T ra d e , 2 0 3 0N e t O i l T ra d e , 2 0 3 0

The M idd le E ast s trengthens its position as the w orld ’s largest o il exporter

M b/d

Proven Gas Reserves

Ultimate remaining resources (including proven reserves) are an estimated 453 - 527 tcm

Ultimate remaining resources (including proven reserves) are an estimated 453 - 527 tcm

World total: 164 tcm at 1 January 2001

56.7

58.5

6.4

11.6

14.9

7.7

8.2

Atmospheric Carbon Dioxide (CO2) Concentrations

270280290300310320330340350360370

1750 1800 1850 1900 1950 2000

parts

per m

illio

n vo

lum

e

Mauna Loa (1958-present)

Siple Station (1750-)

299 ppmv

Highest in last 420,000 yrs

370 ppmvMost recent

Source: C.D. Keeling and T.P. Whorf, Atmospheric CO2 Concentrations (ppmv) derived from in situ air samples collected at Mauna Loa Observatory, Hawaii, Scripps Institute of Oceanography, August 1998. A. Neftel et al, Historical CO2 Record from the Siple Station Ice Core, Physics Institute, University of Bern, Switzerland, September 1994. See http://cdiac.esd.ornl.gov/trends/co2/contents.htm

The Technology Approach

Hydrogen Fuel Cell Vehicles

Zero Net Emission Buildings

Nuclear Power Generation IV

Renewable Energy Technologies

Vision 21: Zero-Emission Power Plant

Bio-Fuels and Power

Carbon (CO2) Sequestration

Deep cuts in emissions require

advanced technologiesSOON

No single technologycan do it all

ENERGY AUDIT IN RETAIL OUTLETS

MAJOR ENERGY CONSUMPTION AREAS IN RETAIL OUTLETS ARE :

• REFRIGERATION AND AIR CONDITIONING

• LIGHTING SYSTEMS

• OTHERS ( ESCALATORS, LIFTS, COMPUTERS,

ETC.)

REFRIGERATION & AIR CONDITIONING (AC) SYSTEMS

REFRIGERATION AND AC SYSTEMS ARE OF 2 TYPES

VAPOUR COMPRESSION REFRIGERATION SYSTEMS (VCS) : Use Compressors

VAPOUR ABSORPTION REFRIGERATION SYSTEM (VAS) : Used where process waste heat or cheap fuels are available

WHAT IS A TON OF REFRIGERATION?

The cooling effect produced is quantified as tons of refrigeration.

1 ton of refrigeration = 3024 kCal/hr heat rejected.

Coefficient of Performance (COP) - If both refrigeration effect and the work done by the compressor (or the input power) are taken in the same units (TR or kcal/hr or kW or Btu/hr), the ratio is

COP = Refrigeration Effect / Work done

Specific Power Consumption = Power Consumption (kW) / Refrigeration effect (TR)

Lower Specific Power Consumption implies better efficiency.

VAPOUR COMPRESSION REFRIGERATION SYSTEM : Components and Principle

VAPOUR COMPRESSION REFRIGERATION SYSTEM

REFRIGERANTS : OZONE DEPLETION AND GLOBAL WARMING

Refrigerants are substances with low boiling points and large latent heats, at pressures above atmospheric pressure. They usually fall under one of the following groups:

CFCs – Chlorofluorocarbons

HCFCs – hydro chlorofluorocarbons

HFCs – Hydro fluorocarbons

HCs – Hydrocarbons

NH3 - Ammonia

CFCs deplete ozone layer and are phased out under Montreal Protocol

HCFCs deplete carbon but to a later extent and would be totally phased out by 2015

CFCs and HCFCs are replaced by HFCs which were developed as recent as 1990

Vapour Compression Cycle•Fluorinated halocarbons are nontoxic, nonflammable, noncombustible and non-corrosive but when released into atmosphere they damage the ozone layer.

• Ammonia, Refrigerant R-717, now limited to the industrial applications because of its high toxicity.

Vapour Absorption Cycle• Ammonia is a refrigerant used with water as the absorbent

( solvent). Use of ammonia is declining with the introduction of refrigerants that have low toxicity and operate at lower system pressures.

• Water is most common refrigerant, and is used in combination with lithium bromide as absorbent.

• Brines and Secondary Coolants :These liquids are cooled or heated by the primary refrigerant and transfer heat energy without change of state.

COMMONLY USED REFRIGERANTS

•The refrigerant type can affect the efficiency of the system by about 10%.

•Too much or too little charge of refrigerant can reduce efficiency.

•Insufficient refrigerant reduces the wetted area of the evaporator, increases the superheat, reduces the suction pressure, increases the temperature and reduces the efficiency.

•Refrigerant, contaminated with air or other gases, will affect the efficiency of the system.

EFFECT OF REFRIGERANTS ON EFFICIENCY OF THE SYSTEM

PERFORMANCE OF VAPOUR COMPRESSION REFRIGERATION SYSTEM

Efficiency of the Vapour Compression Refrigeration System is dependent on the performance of the following :

COMPRESSOR

CONDENSER, COOING TOWER

EVAPORATOR

EXPANSION VALVE

COMPRESSORS

GENERALLY THERE ARE 4 TYPES OF COMPRESSORS USED- CENTRIFUGAL COMPRESSORS- RECIPROCATING COMPRESSORS- SCREW COMPRESSORS- SCROLL COMPRESSORS

These are further classified as - Hermetic Compressors : compressor, motor, shaft and

drive are sealed in a welded casing to contain the refrigerant and lubricating oil

- Semi Hermetic Compressor : similar to hermetic but motor and compressor are in fabricated enclosure with bolted sections

- Open Compressors: external drive shaft that extends through a seal in compressor housing

EVAPORATORS

• EVAPORATOR IS A HEAT EXCHANGER WHERE HEAT IS REMOVED FROM THE SYSTEM (AIR , WATER OR OTHER INTERMEDIATE FLUID) BY THE BOILING OF REFRIGERANT IN THE EVAPORATOR

• HEAT TRANSFER RATES IN EVAPORATOR DEPENDS ON SURFACE AREA, FLUIDS INVOLVED, TURBULENCE IN FLUID STREAMS AND OPERATING TEMPERATURE AND PRESSURE

1) The Evaporator may be refrigerant cooled coils in an air stream (Air Handling Unit- AHU) for Air Conditioning

•The Evaporator may be PLATE HEAT EXCHANGER

•The Evaporator may be SHELL & TUBE HEAT EXCHANGERS with refrigerant in shell or tube sides

EVAPORATORS

4) The Evaporator may be refrigerants coils (DIRECT EXPANSION (DX) COILS) submerged in water or brine tanks

Direct expansion (DX) coils consist of a series of tubes through which refrigerant flows. The tubes are arranged into a number of parallel circuits fed from a single expansion valve. The hot refrigerant vapour is collected in the outlet (suction) gas header. The tubes are finned to increase the heat transfer rate from the medium to be cooled, generally air, to the boiling refrigerant.

EVAPORATORS

Effect of Variation in Evaporator Temperature on

Compressor Power Consumption

Evaporator Temperature

(0C)

Refrigeration Capacity

(tons)

Specific Power

Consumption

Increase in kW/ton (%)

5.0 67.58 0.81 -

0.0 56.07 0.94 16.0

-5.0 45.98 1.08 33.0

-10.0 37.20 1.25 54.0

-20.0 23.12 1.67 106.0

10C raise in evaporator temperature can help to save almost 3 % on power consumption.

CONDENSERS

• A water cooled condenser is generally in loop with a cooling tower•Auxiliary pumps and piping for recirculation of cooling water are required.•Water treatment is required in water recirculation systems.•Space requirements.•Maintenance problems.•Freeze protection for winter operation.

WATER-COOLED CONDENSERS

•Low installation costs, Low maintenance requirements.,•Higher power requirements per kW cooling than evaporative or water-cooled condensers.•Operating difficulties caused by increased condensing capacity and lower loads when operating at low ambient temperatures.•Multiple units are required in large systems.

AIR-COOLED CONDENSERS

EVAPORATIVE CONDENSERS

•Indoor locations are possible.•Water treatment is required.•Space requirements are less than for air-cooled condensers, or shell and tube condensers when a cooling tower is used.

•For a given capacity, less circulating water is required than for a water cooled condenser with a cooling tower

•System pumps are smaller

Effect of Variation in Condenser Temperature on

Compressor Power Consumption

Condensing Temperature

(0C)


(tons)

Specific Power

Consumption

Increase in kW/TR

(%)

26.7 31.5 1.17 -

35.0 21.4 1.27 8.5

40.0 20.0 1.41 20.5

Effect of Poor Maintenance on Compressor Power Consumption

Condition Evap. Temp (0C)

Cond. Temp (0C)


(tons)

Specific Power

Consumption (kW/ton)

Increase in

kW/Ton (%)

Normal 7.2 40.5 17.0 0.69 - Dirty condenser

7.2 46.1 15.6 0.84 20.4

Dirty evaporator

1.7 40.5 13.8 0.82 18.3

Dirty condenser and evaporator

1.7 46.1 12.7 0.96 38.7

COOLING TOWERS

1 deg C cooling water temperature increase may increase A/C compressor kW by 2.7%.

Performance Parameters

a) Range is the difference between the cooling water inlet and outlet temperature

Formula:CT Range (°C) = [CW inlet temp (°C) – CW outlet temp (°C)]

Cold Water Temperature (Out)

Hot Water Temperature (In)

Ran

ge

Ap

pro

ach

Wet Bulb Temperature (Ambient)

(In) to the Tower(Out) from the Tower

Figure: Parameters determining the performance of CT

b) Approach is the difference between the cooling tower outlet cold water temperature and ambient wet bulb temperature

Formula:CT Approach (°C) = [CW outlet temp (°C) – Wet bulb temp (°C)]



Ran

ge

Ap

pro

ach





c) Cooling tower effectiveness (%) is the ratio of range to the ideal range -the difference between cooling water inlet temperature and ambient wet bulb temperature

Formula:

CT Effectiveness (%) = 100 x (CW temp – CW out temp) / (CW in temp – WB

temp)

d) Cooling capacity is the heat rejected in kCal/hr or TR -given as product of mass flow rate of water, specific heat and temperature difference



Ran

geA

ppro

ach





e) Evaporation loss is the water quantity evaporated for cooling duty theoretically, for every 10,000,000 kCal heat rejected, evaporation quantity works out to 1.8 m3

An empirical relation: Evaporation Loss (m3/hr) = 0.00085 x 1.8 x

circulation rate (m3/hr) x (T1-T2)T1-T2 = Temp. difference between inlet and outlet

water.

f) Cycles of concentration (C.O.C) is the ratio of dissolved solids in circulating water to the dissolved solids in make up water

g) Blow down losses depend upon cycles of concentration and the evaporation losses

Blow Down = Evaporation Loss / (C.O.C. – 1)

Follow manufacturer’s recommended clearances around cooling towers and relocate or modify structures that interfere with the air intake or exhaust. Optimise cooling tower fan blade angle on a seasonal and/or load basis. Correct excessive and/or uneven fan blade tip clearance and poor fan balance. On old counter-flow cooling towers, replace old spray type nozzles with new square spray ABS practically non-clogging nozzles. Replace splash bars with self-extinguishing PVC cellular film fill. Install new nozzles to obtain a more uniform water pattern .

ENERGY SAVING OPPORTUNITIES IN COOLING TOWERS

Periodically clean plugged cooling tower distribution nozzlesBalance flow to cooling tower hot water basins. Cover hot water basins to minimise algae growth that contributes to fouling. Optimise blow down flow rate, as per COC limit. Replace slat type drift eliminators with low pressure drop, self extinguishing, PVC cellular units. Restrict flows through large loads to design values. Consider energy efficient FRP blade adoption for fan energy savings

ENERGY SAVING OPPORTUNITIES IN COOLING TOWERS

SPECIFIC POWER CONSUMPTION OF VCS

•Well designed, well maintained, water cooled vapour compression systems, using reciprocating, screw or scroll compressors, for chilled water at about 8°C have COP of 4 to 5.8, Specific Power Consumption in the range of 0.61 to 0.87 kW/TR.

•Centrifugal compressors, which are generally used for cooling loads about 150 TR, can have COP of about 6, Specific Power Consumption of 0.59 kW/TR.

•The COP of systems with air cooled condensers is generally about 20% to 40% higher.

•The COP of well designed small machines like window air conditioners and split air conditioning units are generally in the vicinity of 2.5.

VAPOUR ABSORPTION REFRIGERATION SYSTEM

The Vapour Absorption Systems or Absorption Chillers use heat source to produce cooling effect, have few moving parts which means less noise and vibrations

Vapour absorption process requires two substances with strong chemical affinity at low temperatures.

The commercially manufactures absorption chillers are of two types:

Using Lithium Bromide (absorbent) and water (refrigerant) for chilled water at 5ºC and above. Using Water (absorbent) and Ammonia (refrigerant) for temperatures below 5ºC. A secondary coolant (brine) is required to transfer heat to ammonia.

Absorption Chillers may be single effect or multiple effect machines; the efficiency of multiple effect machines is higher.

How do the chillers work ?

1. Boiling point of the water is a function of pressure. At atmospheric pressure water boils at 100 deg. C. When maintained at high vacuum, water will boil and subcool itself. The boiling point of the water at 6 mmHg (abs) is 3.7 deg. C.

2. Lithium Bromide (LiBr) has the property to absorb water due to its chemical affinity. At higher concentration and lower temperature LiBr absorbs water vapour (refrigerant vapour) very effectively.



3. As Lithium Bromide becomes dilute it loses its capacity to absorb water vapour. It thus needs to be re-concentrated using a heat source. Heat source may be Steam or Flue gases or even Hot water.

PERFORMANCE ASSESSMENT: REFRIGERATION

The specific power consumption kW/TR is a useful indicator of the performance of refrigeration system. By messing refrigeration duty performed in TR and the Kilo Watt inputs measured, kW/TR is used as a reference energy performance indicator.

The refrigeration TR is assessed as TR = Q Cp (Ti – To) / 3024

Where TR is cooling duty Q is mass flow rate of coolant in kg/hr Cp is coolant specific heat in kCal /kg / 0C

Ti is inlet. Temperature of coolant to evaporator (chiller) in 0C.

To is outlet temperature of coolant from evaporator (chiller) in 0C.

CALCULATING THE OPERATING LOAD OF A CHILLER PLANT

Refrigeration plant

Refrigeration plant

Hot well12OC

Cold well8OC

Process

Chilled water flow – 100 m3/hr

Refrigeration TR - 100,000 kg/hr x 1 x 4

3024

- 133.33 TR

Efficiency -Power drawn by compressor, kW

TR

m Cp

120

133.33- = 0.9

OVERALL ENERGY CONSUMPTION

Compressor kW Chilled water pump kW Condenser water pump kW Cooling tower fan kW

Overall kW/TR = sum of all above kW/ TR

COPThe theoretical Coefficient of Performance (Carnot), COPCarnont - a standard measure of refrigeration efficiency of an ideal refrigeration system- depends on two key system temperatures, namely, evaporator temperature Te and condenser temperature Tc with COP being given as:

COPCarnot = Te / Tc - Te

This expression also indicates that higher COPCarnot is achieved with higher evaporator temperature and lower condenser temperature.

But COPCarnot is only a ratio of temperatures, and hence does not take into account the type of compressor. Hence the COP normally used in the industry is given by

Cooling effect (kW)COP =

Power input to compressor (kW)

EFFECT OF EVAPORATOR AND CONDENSING TEMPERATURES ON COP

PERFORMANCE ASSESSMENT: AIR CONDITIONING

In case of air conditioning units, the airflow at the Fan Coil Units (FCU) or the Air Handling Units (AHU) can be measured with an anemometer. Dry bulb and wet bulb temperatures are measured at the inlet and outlet of AHU or the FCU and the refrigeration load in TR is assessed as ;

3024

h h ρ Q TR outin

Where, Q is the air flow in m3/h

is density of air kg/m3

h in is enthalpy of inlet air kCal/kg

h out is enthalpy of outlet air kCal/kg

ENERGY SAVING: STRATEGIES & OPPORTUNITIES

1) MINIMISE REFRIGERATION AND AIR CONDITIONING

USE EVAPORATIVE COOLONG IN DRY AREAS

BUILDING STRUCTURE COOLING

• Wetted Roof Mats / Reflector Tiles etc

• Terrace Gardens

2) OPERATING AT HIGHER EVAPORATOR TEMPERATURE

( 1 deg C higher temperature in the evaporator leads to lowering of specific power consumption by 2-3%)

INCREASE CHILLER WATER TEMPERATURE SET POINT

IMPROVE AIR DISTRIBUTION IN COLD STORAGE

IMPROVE AIR DISTRIBUTION AND CIRCULATION IN AIR CONDITIONED AREA

3) ACCURATE MEASUREMENT & CONTROL OF TEMPERATURE IN VAPOR COMPRESSION MACHINE BY THE USE OF ELECTRONIC EXPANSION VALVES

3) REDUCTION IN HEAT LOADS

UNNECESSARY HEAT LOADS LIKE OVENS ETC. SHOULD BE KEPT OUT

USE OF FLASE CEILINGS

USE OF PREFABRICATED MODULAR COLD STORAGE UNITS

CIRCULATING FANS IN COLD STORAGE THE BE PUT IN AUTO MODE FOR ON & OFF


5) MINIMIZE HEAT INGRESS PROVIDING AN ANTE ROOM BEFORE COLD STORES WITH A

HIGH SPEED DOOR BETWEEN THE COLD STORE AND THE ANTE ROOM. (AIR INFILTRATION REDUCES FROM 2900 M3 TO 700 M3 PER TRUCK LOAD – 76% REDUCTION)

CHECK & MAINTAIN THERMAL INSULATION: UNDER INSULATION ON THE CEILING OF THE TOP MOST FLOOR

INSULATE PIPE FITTING : VALVES , FLANGES ETC. USE LAND SCAPING TO REDUCE SOLAR HEAT LOAD USE GLASS WITH LOW SOLAR HEAT GAIN CO-EFFICIENT &

THERMAL CONDUCTIVITY USE LOW CONDUCTIVITY WINDOW FRAMES LIKE PLASTIC PROVIDE INSULATION ON SUN FACING ROOFS & WALLS USE AIR CURTAINS AT MAIN DOORS, PVC STRIP CERTAIN ETC.

FOR AIR CONDITIONED SPACES.


6) REDUCE VENTILATION HEAD LOAD

REDUCE VENTILATION REQUIREMENT BY OZONE DOSING (Ventilation air requirement reduced from 15cfm per person in a non smoking area to 5 cfm, but residual ozone shold not be greater than 0.05 ppm ASHRAE)

AIR TO AIR HEAT EXCHANGER FOR PRE COOLING THE VENTILATION AIR

• Heat Pipes

• Heat Wheels

7) THERMAL STORAGE FOR MAX. DEMAND CONTROL BY ICE BANK SYSTEM


8) USE EVAPORATORS AND CONDENSERS WITH HIGHERHEAT TRANSFER EFFICIENCY

USE HEAT EXCHANGERS WITH LARGE SURFACE AREA(ADDITIONAL CHILLERS/CONDENSERS IN PARALLEL CAN LEADTO SIGNIFICANT ENERGY SAVING)

USE PLATE HEAT EXCHANGERS FOR CONDENSER COOLING(PHE HAVE APPROACH OF 1 oC TO 5 oC INSTEAD OF 5 oC TO 10 oC FOR SHELL & TUBE HEAT EXCHANGER)

AVOID USE OF AIR COOLED CONDENSERS FOR LARGE COOLING


USE BUILDING THERMAL INERTIA IN AC FOR EARLY SWITCH OFF MAINTAIN CORRECT ANTI FREEZE CONCENTARTION INSTALL A CHILLER CONTROL SYSTEM TO CO-ORDINATE MULTIPLE

CHILLERS OPTIMIZE WATER/ BRINE/ AIR FLOW RATES : CHILLED WATER

2.4GPM/TR; COOLING WATER 3 GPM/TR; FOR AC AIR FLOW RATE 400CFM/TR

REGULAR DEFROSTING OF THE EVAPORATOR FOR ENHANCED HEAT TRANSFER EFFICIENCY (DEFROST ON DEMAND CONTROLLER)

REGULAR CHECKS FOR CONTROL SETTINGS AS THEY CAN DRIFT OVER A PERIOD OF TIME

CLEAN FOULED HEAT EXCHANGERS PURGE THE CONDENSER OF AIR DO NOT OVER CHARGE OR UNDER CHARGE COMPRESSOR OIL

ENERGY SAVING OPPORTUNITIES IN NORMAL OPERATION

• Lighting energy consumption represents 20-45% in commercial buildings and 3-10% in industrial plants

• Significant energy savings can be realized with a minimal capital investment

ENERGY EFFICIENCY IN LIGHTING SYSTEMS

Lighting Terms

Circuit Watts is the total power in Watts drawn by lamps and ballast in a lighting circuit

Luminous Efficacy is the ratio of light output to Watt input. Unit: lumens per watt (lm/W)

Lamp Circuit Efficacy is amount of light (lumens) emitted by a lamp for each watt of power consumed by the lamp circuit, i.e. including control gear losses. This is a more meaningful measure for those lamps that require control gear. Unit: lumens per circuit watt (lm/W)

Other Lighting Terms

Average maintained illuminance is average of lux levels measured at various points in a defined area.

Color rendering index (CRI) is a measure of the degree of color shift that objects undergo when illuminated by the light source as compared with those same objects when illuminated by a reference source of comparable correlated color temperature.

In general, a lower CRI indicates that some colors may appear unnatural when illuminated by a lamp.

Color rendering is measured on an index from 0-100, with natural daylight equal to 100.

INCANDESCENT LAMPS Incandescent lamps :

Light is produced by passing electric current through a thin fire filament usually tungsten. Also known as GLS (General Lighting Service).

Reflector lamps :

Basically incandescent, with a high quality internal mirror, which follows same parabolic shape of the lamp. Reflector is resistant to corrosion, thus making the lamp maintenance free and efficient in output.

Halogen lamps:

Also called as tungsten-halogen lamp. Halogen lamps are high pressure incandescent lamps containing halogen gases such as iodine or bromine which allow the filaments to be operated at higher temperatures and higher efficacies. At high-temperatures, chemical reaction involving tungsten and the halogen gas recycles evaporated particles of tungsten back onto the filament surface

GAS DISCHARGE LAMPS

Fluorescent Lamps (FTL) Compact Fluorescent Lamps (CFL) Mercury Vapour Lamps Sodium Vapour Lamps Metal Halide Lamps

Light is produced by excitation of gas contained in either a tubular or elliptical outer bulb

LUMINAIRE

A complete lighting unit consisting of lamps and the parts designed to distribute the light, to position and protect the lamps, and to connect the lamps to the power supply Silvered glass, stainless steel, chromium plate and vitreous enamel

GEAR Ballast

A device required by discharge lamps such as fluorescent lamps to regulate voltage and current supplied to the lamp during start and throughout operation

Energy loss is typically 10-20 % of total energy in conventional ballast’s

Igniters Used for starting high intensity Metal Halide and

Sodium vapour lamps

Illuminance Lumen (or Luminous flux) is a measure of

the total light output of the lamp. A lamp's lumen output rating expresses the total amount of light the lamp emits in all directions per unit time. Light sources are labeled with an output rating in lumens.

Density of luminous flux incident upon a surface. Illuminance is measured in lux (lumens/square meter).

Lux (lx) is illuminance produced by a luminous flux of one lumens uniformly distributed over a surface area of one square metre

Sunrise & Sunset : 500 lux, Summer midday : 100000 lux Winter midday : 10,000 lux, Full Moon : 0.25 lux

Luminous Performance Characteristics of Commonly Used Luminaries

Lum / Watt Type of Lamp

Range Avg.

Color Rendering Index

Typical Application Life

(Hours)

Incandescent 8-18 14 Excellent Homes, restaurants, general lighting, emergency lighting

1000

Fluorescent Lamps

46-60 50 Good w.r.t. coating

Offices, shops, hospitals, homes

5000

Compact fluorescent lamps (CFL)

40-70 60 Very good Hotels, shops, homes, offices

8000-10000

High pressure mercury (HPMV)

44-57 50 Fair General lighting in factories, garages, car parking, flood lighting

5000

Halogen lamps 18-24 20 Excellent Display, flood lighting, stadium exhibition grounds, construction areas

2000-4000

High pressure sodium (HPSV) SON

67-121 90 Fair General lighting in factories, ware houses, street lighting

6000-12000

Low pressure sodium (LPSV) SOX

101-175 150 Poor Roadways, tunnels, canals, street lighting

6000-12000

METHODOLOGY OF LIGHTING SYSTEM ENERGY EFFICIENCY STUDY

Step-1 : Inventorise the Lighting System elements, & transformers in the facility as per following typical format.

S. No.

Plant Location

Lighting Device

& Ballast Type

Rating in Watts

Lamp & Ballast

Population Numbers

Use / Shifts as I / II / III shifts /

Day

Lighting transformer /rating and profile

No. Plant Location

Lighting Transformer Rating

Numbers Installed

Measurements Volts / Amps / kW/ Energy

METHODOLOGY OF LIGHTING SYSTEM ENERGY EFFICIENCY STUDY

Step-2: Measure and record lux levels using lux meter at various plant locations (daytime and nighttime) alongside number of lamps “ON” during measurement

Step-3: Measure and record voltage and power consumption at various input points-distribution boards or lighting transformer

Step-4: Compare lux values with standard Step-5: Analyse failure rates of lamp, ballast and

actual life expectancy from past data Step-6: Generate improvement options

ENERGY SAVINGS IN LIGHTING SYSTEM

Make maximum use of natural light (North roof/translucent sheets/more windows and openings)

Switch off when not required Modify lighting layout to meet the need Select light colours for interiors Provide lighting controls- timer switches / PV controls Provide lighting Transformer to operate at reduced voltage Install energy efficient lamps, luminaries and controls Clean North roof glass, translucent sheet and luminaries

regularly Task lighting

•On/off flip switches

•Timer control & auto timed switch off

•Presence detection

•Group Switching

•Day light linking

•Photo sensors

LIGHTING CONTROLS

ENERGY CONSERVATION IN RETAIL SECTOR

•In USA Energy Consumption in retail sector is US $ 13 Billion/yr

•Potential for conservation is 15-23 % i.e. US $ 3 Billion/yr

•Shaws Supermarkets has saved 20 million kWh per year as a result of lighting retrofits

•Wal Mart has achieved an annual savings of 250 million kWh by installing T8 lamps and electronic ballasts, enough to power 20,000homes

•The Heschong Mahone Group has statistically demonstrated an increase in sales of about 40% in retail stores which use diffusing sky-lights in comparison to stores without daylight

•REFRIGERATION AND AIR CONDITIONING

•LIGHTING SYSTEMS

•The percentage share of these systems in the energy bill is dependent on the climate of the region

•For a typical hot and humid climate Refrigeration and Air Conditioning accounts for about 45- 65% energy consumption

•For Cooler climate lighting usually represents 30-50% of energy use, however in such cases the energy consumption for space heating will also have to be considered

MAJOR ENERGY CONSERVATION AREAS IN RETAIL SECTOR

Costco Wholesale Corporation, a membership warehouse club with 350 locations worldwide has implemented the following measures resulting in annual energy conservation of 17%. It has

• Installed skylights in its stores to reduce lighting loads.

• Implemented an energy management system that automatically

regulates its energy needs throughout its stores.

• Reduced indoor lighting by two-thirds during the day

• Lowered thermostats for heat from 68 to 63 degrees, and for

cooling from 72 to 78 degrees.

EXAMPLES OF ENERGY CONSERVATION IN RETAIL SECTOR

EXAMPLES OF ENERGY CONSERVATION IN RETAIL SECTOR

Wal-Mart which has about 600 outlets in US has:

• Reduced interior lighting in all California stores without skylights by turning off every third fixture.

• Included a day lighting system on all recently constructed buildings. This system uses a combination of light sensors and skylights to maximize the use of natural light.

• Installed T8 low-mercury fluorescent lamps and electronic ballasts (the most efficient lighting system on the market) at new stores.

• Since the mid-1990s, all Wal-Marts built in California have white membrane roofs. The high solar reflectivity of this membrane results in lowering the cooling load by about 8 percent.

THIS RESULTED IN ANNUAL SAVINGS OF 250 Million kWh

•Replace any metal halide, high-pressure sodium or mercury vapor lighting with more efficient, high intensity fluorescent (HIF). In addition to energy savings, the HIF has better color and allows instant-on/re-strike.

•Use day lighting where possible. Consider skylights in the ceiling and glazing with light shelves around the perimeter.

•Limit outside air entering the facility during cold and hot weather.

•Consider installing demand controlled ventilation that adjusts outside air according to the number of customers and employees, rather than assumed occupancy.

MAJOR ENERGY CONSERVATION OPTIONS IN RETAIL SECTOR

•Install variable speed drives on pumps and fans with long run hours and variable loads.

•Install more energy efficient heating equipment.

•Install more efficient cooling equipment. In dry regions consider evaporative cooling.

•Install energy management systems in all stores for scheduling and controlling HVAC and lighting. Be sure it has remote access capability

MAJOR ENERGY CONSERVATION OPTIONS IN RETAIL SECTOR

benefiting from energy conservation in retail establishments

Documents

tons of refrigeration

ton of refrigeration

energy conservation

input power

emission power plantbiofuels

cooling effect

ozone layer

historical co2 record