Wednesday, December 5, 2012

Heating cost comparisons

What is the cheapest way to heat your home?  I'll crunch the numbers for a house in Nova Scotia.

Electric baseboard heaters are cheap to install, but expensive to use.  The current cost of electricity in NS is 14.6c/kWh tax in.  With one kWh of electricity providing 3412 BTU of heat, electric heating costs 4.28c/kBTU.

If you use the time-of-day tariff,  off-peak electricity costs 8.15c/kWh tax in.  That reduces electric heating costs at night and weekends to 2.39c/kBTU.

Furnace oil is selling for $1/L, and provides ~36kBTU when burned.  With a 90% efficient condensing boiler, the cost is 3.09c/kBTU.

Discount propane sells for ~60c/L at Costco, and provides ~26kBTU when burned.  With a 90% efficient condensing boiler, the cost is 2.56c/kBTU.

Wood pellets provide ~8kBTU/lb, and sell for ~$5 for a 40lb bag.  At 90% efficiency, the cost of heat is 1.74c/kBTU.

Heating with wood pellets is pretty cheap, but still not the cheapest.  A geothermal heating system will have a COP of at least 3.0 (4.0 can be achieved with new high-efficiency heat pumps).  Take the 4.28c/kBTU cost of electricity and divide by the COP (3.0) to get a heating cost of only 1.43c/kBTU.  With a time-of-day tariff and off-peak use, the rate is just 0.8c/kBTU.

Don't forget the cheapest (free) source of heat - the sun.  So on those sunny winter days, open the curtains, raise the blinds, and let the sun shine in!

1 comment:

Viola said...

Thank you for the very useful information Ralph. Dad has been thinking of alternate heat sources lately. I'll show this article to him tomorrow. Tonight he is working the Salvation Army Kettle in the Mayflower Mall.

Love & hugs, Mom