B- Conducting an Energy Audit

8/8/2019 B- Conducting an Energy Audit

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Conducting An Energy Audit

AEE/ Certified Energy Manager CEM AEE/ Certified Energy Manager CEM ® ® BB - - 11



Conducting Energy Audits

Lay out ± Process FD-

Operating Conditions

General

Systems

Boiler & Steam SystemHVAC

Elec. Supply System

Water systems

Compressed Air System

Lighting

Motors and Drives

Processing Lines

Building Envelope

Energy Data

Electricity Bills

Fuel Bills

Water Bills

Step 1 : Data Collection Step 2 :Pre. Audit Report

Energy Accounting

Normalization

Time Plotting of data

Identifying ECO

Step 3 :Facility Inspection

Detailed Measurements

Categorizing Consumption

Systems Detailed Specs. Andoperating conditions

Step 4 :Detailed Audit Report

Detailed Inventory

Specific Energy Consumption

Conceptual Design for ECO

Economic Evaluation and Analysis



G oals of the energy audit are to :Clearly identify types and costs of energy use

Understand how that energy is being used andpossibly wasted

Identify and analyze more cost-effective ways of using energy- Improved operational techniques

- New equipment

Perform an economic analysis on those alternativesand determine which are cost-effective for your business or industry

AEE/ Certified Energy Manager CEM AEE/ Certified Energy Manager CEM ® ® BB - - 2 2



Analysis of BillsT he audit must begin with a detailed analysis of theenergy bills for the previous twelve months. T his isimportant because :

The bills show the proportionate use of each different energysource when compared to the total energy bill.

An examination of where energy is used can point outpreviously unknown energy wastes, and

T he total amount spent on energy puts an obvious upper limiton the amount that can be saved.









Av. Load Duration Curve

0

200

400

600

800

1000

1200

744 1464 2208 2928 3672 4416 5136 5880 6552 7296 8016

Hrs / Year

k W



A complete analysis of the energy bills for a facility

requires a detailed knowledge of the rate structures ineffect for the facility.

T o accurately determine the costs of operating individualpieces of equipment, break down energy bills into their

components (e.g. demand charge and energy charges for the electric bill).

T his breakdown also allows more accurate savingscalculations for Energy Management Opportunities(EMOs) such as high-efficiency equipment, rescheduling

of some on-peak electrical uses, etc.




S teps in the On-site Energy Audit

1 . Identify layout and operating schedule for facility.

Make a plan or sketch of the building(s) whichshows building sizes, window areas, and walland roof composition and insulation

2. Compile an equipment inventory.

List all energy consuming equipment, with hours of use each year and energy ratings or efficiencies




3 . Determine the pattern of building use to show annual

needs for heating, cooling and lighting

4. Conduct a room-by-room lighting inventory

± Light fixtures ± Lamp types, size and numbers ± Levels of illumination ± Uses of task lighting




AEE/ Certified Energy Manager CEM AEE/ Certified Energy Manager CEM ® ® BB - -99

Energy Balance for Facility

F acility

Electricity2,597,700 kWh

Natural G as329,863 GJ

ighting

130,560 kWh

Boiler

329,863 GJ

M otors1,516,619 kWh

Compressors116,379 kWh

HVAC34,286 kWh

Chillers274,560 kWh

Electric Heaters100,100 kWh

M iscellaneous260,000 kWh

Total: 2,432,501 kWh/yr



AEE/ Certified Energy Manager CEM AEE/ Certified Energy Manager CEM ® ® BB - -10 10

D emand Balance for a FacilityElectricity

345-378 kW

Lighting18 kW

Chillers34.3 kW

Electric Heaters13 kW

F acilityM otors

197.1 kW

Compressors14.9 kW

HVAC17.1 kWM iscellaneous

35 kW

Total: 329.4 kW



G eographic Location / D egree D ays /Weather D ata

Geographic location of facility and weather data for that location are important.

Obtain average degree days for heating and coolingfor that location for the past twelve months from: ± Closest weather station, or

±Local utility

Degree-day data is very useful in analyzing energyneeded to heat or cool facility.




H eating degree days ( H DD) and cooling degree days

(CDD) are separate values to a particular geographiclocation.

T he degree day concept assumes:

T he average building has a desired indoor temperature of 21 .1° C,

2.8 °C of this is supplied by internal heat sources such aslights, appliances, equipment, and people.

@ The base for computing degree-days is 18.33°C.






Facility Layout

Obtain the facility layout or plan; review it todetermine:

± F acility size ± F loor plan ± Construction features

(wall and roof material, insulation levels, door and window sizes and construction)




Operating Hours

Obtain operating hours for facility

± H ow many shifts does the facility run? ± Is there only a single shift? ± T wo? T hree?

Knowing the operating hours in advance gives someindication as to whether any loads could be shifted to off-peak times.




Equipment List

Get equipment list for facility and review it beforeconducting audit.

Identify all large pieces of energy-consumingequipment such as:

± H eaters, air conditioners, water heaters, and specificprocess-related equipment

Equipment list and data on operational uses of equipment provide understanding of major energy-consuming tasks or equipment at facility.




Nine M ajor S ystems To Consider

1 . Building Envelope2. HV AC System3 . Electrical Supply System

4. Lighting5. Boiler and Steam System6. H ot Water System7. Compressed Air System8. Motors and drives9. Special Purpose Process Equipment




As you examine each system, you should ask:

1 . What function(s) does this system serve?

2. H ow does this system serve its function(s)?

3 . What is the energy consumption of this system?

4. What are the indications that this system is probably

working ?




5. If this system is not working, how can it be restoredto good working condition?

6. H ow can the energy cost of this system be reduced?

7. H ow should this system be maintained?

8. Who has direct responsibility for maintaining andimproving the operation and energy efficiency of this

system?




P reliminary Identification of EnergyM anagement Opportunities (E M Os)

During the on-site audit, take notes on potentialEMOs that are evident.

In general, devote the greatest effort to analyzingand implementing the EMOs which show the greatestsavings, and the least effort to those with thesmallest savings potential.

Identifying EMOs requires a good knowledge of energy efficiency technologies available to do thesame job with less energy and cost.




The Energy Audit Report

T he energy audit report

± Explains the final results of the energy analyses

± Provides energy cost saving recommendations.




Energy Audit Report Format

Executive SummaryBrief summary of recommendations and cost savings

IntroductionPurpose of the energy auditNeed for a continuing energy cost control program

Facility DescriptionSize, construction, facility layout, and hours of

Operation, equipment list, with specifications




Energy Bill AnalysisUtility rate structuresT ables/graphs of energy consumptions and costsDiscussion of energy costs and energy bills

Energy Management Opportunities (EMO¶s)Listing of potential EMOs

Cost and savings analysisEconomic evaluation

Energy Action PlanSchedule for implementing EMOsDesignation of an energy monitor

Conclusion Additional comments not otherwise covered





EmissionF

actors

Emissions by Fuel Type Ton CO 2 Ton SO 2 Ton NOx

1 ton Mazout 3.229600 0.080000 0.0040001 ton Solar 3.229600 0.040000 0.0040001 m 3 of Natural Gas 0.001950 0.000000 0.0000001 kWh of Electricity (assumesemissions are from a central utility-owned power stration) 0.000775 0.000019 0.0000021 ton of LPG 3.027000 0.000000 0.000000

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B- Conducting an Energy Audit