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Putting things in Perspective

I&M Plan WorkshopJuly 9, 2008

or, “Why bother with your Natural Gas Engine?”

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Relative Cost per BtuEnergy Unit BTU Content $ / Unit Energy Cents per MBtu

1 Lb. Coal 12,500 $ .06 0.47

1 Therm Natural Gas 100,000 $ 1.28 1.28

1 Gal. Propane 91,000 $ 4.75 5.22

1 Gal. Diesel #2 139,000 $ 5.00 3.60

1 Gal. Gasoline 125,000 $ 4.57 3.66SCE TOU-8 Primary (Summer)

Off-Peak kWh 3412 .0894 2.62Mid-Peak kWh 3412 .1515 4.44On-Peak kWh 3412 .2896 8.49Annual Average kWh 3412 .1297 3.80

July, 2008

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Energy Unit Cost/MBtu C.O.P Cents per Ton-HrNatural Gas Engine 1.28 1.9 8.1

SCE TOU-8 Secondary (Summer)

Off-Peak kWh 2.62 5.5 5.7Mid-Peak kWh 4.44 5.5 9.7On-Peak kWh 8.49 5.5 18.5

400 Ton Electric Chiller costs $74 per Hour to operate On-Peak

Gas Chiller cost is $32 to $56 per Hour at all times…

Relative Cost per Btu(IC Engine Driven HVAC Chiller)

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Engine Cost/MBtu Heat Rate Cents per HP-Hr

Natural Gas 1.28 8890 11.4

SCE TOU-8 Secondary (Summer)

Electric Motor Efficiency

Off-Peak kWh 2.62 .95 7.0Mid-Peak kWh 4.44 .95 11.9On-Peak kWh 8.49 .95 22.8

200 HP Electric Motor costs $46 per Hour to operate On-Peak

Gas Engine cost is $23 per Hour at all times…

Relative Cost per Btu(IC Engine Prime Mover)

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Prime Mover Operating Cost Comparison

.00

.20

.40

.60

.80

1.00

1.20

1.40

.01 .02 .03 .04 .05 .06 .07 .08 .09 .10 .11 .12 .13 .14 .15 .16 .17 .18 .19 .20 .21 .22 .23 .24 .25

Electricity Cost ($ per kWH)

Gas C

ost

($ p

er

Th

erm

)

Energy Costs Favor Gas Engines

Energy Costs FavorElectric Motors

“When Do Engines Save Money?”

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Steve Rawski

Principal Engineer

(714) 634-3246

srawski@semprautilities.com

Remember, your Gas company Representatives are here to help…

Understanding the Regulations

Developing and Implementing a Long Term Plan.