Resistance is futile – Conversion Factors

While no one can say those in the “Green” / Energy Efficiency fields march in lock step like the Borg, I couldn’t resist using that line from Star Trek. The reason, well it appears that a big part of the collective is moving towards using kBtu/SF for measuring usage. For more on this aspect & an interesting look at the numbers I invite you to check out Joshua Lloyd’s post on this subject; Sym-Home Energy Targets (and maybe to see what that picture is about.)

For those wondering what kBtu/SF is, it simply measuring home many BTU’s are used per square foot of space. In this case the k stands for 1000, so how many thousands of BTU’s are used per square foot. Ahh, but how does one get that number? Well in keeping with a promise back from my CEA training, here is a conversion chart to convert the most standard (and not so standard) items into kBtu.

Source	Measurement	Multiply / Conversion Factor
All	kBtu	1
	MBtu	1,000
	MMBtu	10,000
	Quad	10,000
Electricity – Site	kWh	3.41
	MWh	3,412
	GWh	3,412,141
Electricity – Primary / Source	kWh	9.77
Electricity – Primary / Source	MWh	9,774
Natural Gas	cf	1.03
	ccf	102.9
	kcf	1,029
	Mcf	1,029,000
	Therms	100
	cubic meters	36.34
Propane	cf	2.52
	kcf	2,518.5
	Gallons	91.65
	liters	23.83
Kerosene	Gallons	135
Kerosene	liters	35.1
Wood *	Tons	15,380
	Cord	30,760
	Face Cord	10,243
Fuel Oil (No. 1, 2, 4), Diesel	Gallons	138.7
	liters	36.06
	Barrel	5,825.2
	Short Ton	38,570
Fuel Oil (No. 5, 6) aka residual	Gallons	149.69
Fuel Oil (No. 5, 6) aka residual	liters	38.92
Coal (anthracite) *	Tons	25,090
	Lbs	12.55
	kLbs	12,545
	MLbs	12,545,000
Coal (bituminous) *	Tons	24,930
	Lbs	12.47
	kLbs	12,465
	MLbs	12,465,000
Gasoline (Pure)	Gallons	125
Gasoline (10% Ethanol)	Gallons	120.9
E85	Gallons	90.5
Ethanol	Gallons	84.4
Methanol	Gallons	62.8
District Steam *	Lbs	1.19
	kLbs	1,194
	MLbs	1,194,000
	therms	100
District Hot Water *	therms	100
District Chilled Water *	Ton Hours	12

* These numbers can vary so when in doubt we defaulted with ENERGY STAR’s numbers used for Portfolio Manager. For example the wood figure can vary based on type of wood, wetness, etc… For more on the numbers for wood; Wood Values.

For example – a 2432 SF house that used 364 Gallons of Propane last year & 10505 kWh’s of Electricity would = 28.46 kBtu/SF — (10505 kWh times 3.14 = 35,843.06) + (364 Gal times 91.65 = 33,359.73) = 69,202.79 — divide 69,202.79 by 2432 Square Feet you get 28.46.

A few more interesting conversions;