On June 7, the BDN ran a story “Is natural gas the answer?” which provided a useful, but limited, table illustrating the heat output and the purchase price of various heating fuels commonly available in this area. While this information is interesting, it did not include the actual cost of the heat delivered to the home because it left out the essential part of the equation, the heating system efficiency. Additionally, the main action that most homeowners can do to reduce their heating costs was not mentioned: increase the insulation value of the home first, to reduce heat requirements forever before spending money on different heating systems.

To address the first limitation, we need to consider the heating system type, the manufacturers’ claimed efficiencies, and calculate the cost per Btu delivered to the home living space using the purchase price of fuel displayed in the BDN table. It claimed efficiencies may be somewhat exaggerated as they may not account for heat loss incurred during startup or shutdown of the system, standby losses, or heat lost from the pipes or ducts in basements and elsewhere. All final prices per million Btu below represent the cost for the heat delivered to the living space from new heating systems, not older, less efficient systems. I have added three additional systems to the BDN’s table.

Oil boiler-furnace with 83 percent efficiency and cost per gallon of $4.45 yields $38.85 per million Btu.

Natural gas boiler-furnace with 83 percent efficiency and cost per therm of $1.77 yields $21.33 per million Btu.

Propane vented heaters with 88 percent efficiency and cost per gallon of $3.60 yields $44.47 per million Btu.

Hardwood in 65 percent efficient wood stove and delivered for $225 per cord yields $17.31 per million Btu.

Wood pellets in 80 percent efficient stoves and delivered for $250 per ton yield $19.05 per million Btu.

Electric resistance at 100 percent efficiency and $0.16 per kwh yields $46.89 per million Btu.

Electric thermal storage at 100 percent efficiency and off-peak at $.011 per kwh $32.24 per million Btu.

Hallowell air source heat pump with 250 percent efficiency and $0.16 per kwh yields $18.76 per million Btu.

Ground source heat pumps with 300 percent efficiency and $0.16 per kwh yields $15.63 per million Btu.

When we apply the system efficiency to each calculation, we now have the true cost of the delivered heat to the home, and it can be surprising. The last three options were not mentioned in the article. Off-peak electricity’s discount brings electric thermal storage systems below current oil and propane delivered costs. But the best story is that heat pumps’ efficiencies can reduce cost of home heating lower than even hardwood firewood. With delivered the costs of $18.76 per million Btu from efficient heat pumps compared to the most efficient oil system at $38.85, a consumer can save more than 50 percent of the operating costs at today’s prices.

Both new northern climate air source heat pumps and the more established ground source heat pumps deliver the lowest cost, hassle-free heating on the market today, and some are manufactured right here. Hallowell International in Bangor is manufacturing and selling advanced air source heat pumps to provide heat and cooling for northern climates with average efficiencies of 250 percent, extracting heat efficiently down to -20 degrees F and colder. They use an air delivery system, so they can be used in new construction or for replacement systems wherever consumers have hot air furnaces, and you’ll get whole house air conditioning as well. Currently these are available through a local contractor.

In Brewer, Nyle Corp. pioneered the development of cold climate air source heat pumps. Nyle is currently testing an efficient air source heat pump boiler for use with baseboard heating systems for northern climates. A release date for this product has not yet been announced, but testing continues and perhaps a product will be marketable in the next year.

Will electricity pricing be stable in the future? New England electricity generation prices generally track the price of natural gas since it is the energy source for 50 percent of New England electricity. Distribution costs have been reduced over the past six years and have leveled off, so perhaps future increases will track inflation. Transmission costs, which are now about 5 percent of the total residential electricity bill, will likely rise somewhat in the future as new transmission lines are built to serve new load and new renewable generation currently planned.

Electricity can be generated here from many sources including these that are native to the U.S.: domestic natural gas, coal, nuclear, hydro, wind, wood, solar and tidal (I leave oil out; it’s more valuable for other uses). The system to deliver this electricity to Maine homes is already in place. All we have to do is use it wisely in these very efficient heat pump heating systems.

Calvin Luther is a business analyst for Bangor Hydro-Electric Co.