Home Heating Costs
There can be no doubt anymore that knowledge applied to house building and home heating leads to money in the pocketbook for years to come. The Geophysical Institute's quarterly journal The Northern Engineer is responding to the high level of public interest in energy conservation by frequently carrying articles on this general subject.
One particularly interesting article by Carol Lewis, soon to appear in The Northern Engineer, contains information on fuel costs. Her figures are for Fairbanks in early 1979, but one can use the information she gives to calculate fuel costs at any location. So doing, one can make an informed judgment on which is the best fuel to use.
A slightly smaller than average but well-built house will require about 1000 gallons of No. 2 fuel oil for annual heating. According to Ms. Lewis, a gallon of fuel oil contains 135,000 BTU's, but typically it is burned with an efficiency of only 70%. Therefore the 1000 gallons of fuel oil will yield 94.5 million BTU's, enough to heat a house of floor area 600 square feet. In Fairbanks, oil now costs $0.62 gallon, so the annual fuel bill would be $620.
Coal burned at 55% efficiency will yield about 13 million BTU's per ton. To heat the sample 600-square-foot house would require 7 tons at $51.50 per ton or $364 per year.
Propane with 21,550 BTU's per pound burned with 70% efficiency and a cost of $24 per 100 lbs. leads to an annual heating bill of $1503 for the sample house.
Electricity gives 3413 BTU's per kilowatt hour and now costs about 5.7 cents per KWh in Fairbanks. It can be used with 100% efficiency, so the 27,688 KWh required to heat the sample house gives an annual heating cost of $1578.
Black spruce contains about 18.5 million BTU's per cord and probably can be burned with an efficiency near 40%. So burned, 12.8 cords is required to heat the sample house. At $65 per cord, the annual heating cost is $832.
Interestingly enough, the amount of heat available in different kinds of wood depends essentially only on the density of the wood. In millions of BTU's per cord, black spruce has 18.5, paper birch 23.6, cottonwood 14.6, aspen 16.3 and Sitka spruce 17.2 (assuming 80 cubic feet of wood fiber per cord--the total volume of a cord being 128 cubic feet).
From all this it would seem that--at least in Fairbanks--coal is cheapest and electricity most expensive. A word of caution though. Don't forget about the rest of the utility bill, including lights and electrical power for other purposes. When these are added into the total bill, electricity does not fare so badly. The reason is that much of the electrical energy required for these other purposes can be included in--not added to--the requirement for house heating.
