Energy Conversion Info
- FYI from the Center for Renewable Energy & Sustainable Technology (CREST)
Date: Thu, 01 Mar 2001 19:08:57 -0500
From: "Bion D. Howard" <bdhoward@...>
Subject: Cost per BTU
Cost per BTU
Pretty useful little table, with a couple of caveats.
$/Kwh (3,412Btus/Kwh ?) -- is only the conversion for the electric power
used on site. The actual primary energy needs to be recalculated to
reflect the losses of generation, transmission, etc. from plant to property
line so conveniently disguised by the "site energy" factor. For this you
need the "heat rate" which can be increasingly hard to uncover now that
utilities are mixing power across service territory boundaries from
different generation modes.
try ~ 9,000 Btus/Kwh (lots of hydro, nuclear, non-fossil, local) to
a top end of about 15,000 Btus/Kwh (extremely dirty fuel in very
inefficient plant, transported over long distances.)
$/Square Foot of Solar Aperture (100,000Btus/SF) - needs to be calculated
on the basis of a competent annual energy simulation, using accurate
climate data, and also should be properly discounted over the life-cycle of
the solar collection device.
-- Bion Howard
=== you wrote
>One bit of data, in this calculation, that only you can most easily and============
>accurately provide, is the cost per purchased fuel unit at your site:
>Such fuel associated costs might be labeled:
>$/therm of gas (100,000Btus/therm),
>$/Kwh (3,412Btus/Kwh ?),
>$/cord firewood (80-120,000Btus/cord ?),
>$/Square Foot of Solar Aperature (100,000Btus/SF)
>$/LPG (propane) @ 95,475 btus/gal.
>$/Coal (lignite) @ 14,940 btus/lb.
>$/Kerosene @ 137,900 btus/gal.
>$/#2 Oil @ 138,690 btus/gal
|| Contact: Bion D. Howard, President
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