# Defining a different fuel unit

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I am trying to create a different natural gas unit. Call it "mine"? I define the Btu/unit in the new fuel meter. I assign the new fuel meter to the Air-side and Water-Side equipment. Then I compare the number of fuel units (eQuest doesn't provide a way to change "Therms" in the ES-D report - that I could find - I didn't review the DOE2 manual to see if it is possible). I calculate the ratio of Btu/unit between "Therm" and "mine". I would expect that ratio to be the same as the ratio of units consumed between the two simulation runs. But this, somewhat poorly organized, table demonstrates my confusion:

ES-D "Therms"

Meter Btu/unit

ES-D Cost

mine

37948

35,724

\$26,230

therm

15360

100,000

\$10,617

ratio

2.47

2.80

2.47

Christopher R. Jones, P.Eng.
Technical Specialist
Sustainability & Energy

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T +1 416-644-0252

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Joined: 2017-10-12
Reputation: 0

Are the two fuels being combusted in the same process, or is ?mine? something equivalent to a purchased steam where the client is only billed for the latent energy? If the issue could be traced to a difference in combustion efficiency maybe that can explain the difference (purchased fuel vs raw fuel) or narrow down the equipment efficiency that may be varying between runs.

David

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Joined: 2012-05-08
Reputation: 1

The two fuels serve that same combustion purpose. I am not sure how the equipment efficiencies would figure into the equation. DOE2 calculates the BTUs combusted then converts to the meter fuel unit. The total BTUs combusted remains the same between the two runs therefore I would expect those ratios to all be the same.

Christopher R. Jones, P.Eng.
Technical Specialist
Sustainability & Energy

[cid:image001.png at 01D33E7C.796EFCE0]
T +1 416-644-0252

2300 Yonge Street, Suite 2300