Energy-efficient heat pumps

In his “One View” of March 27 [Electrifying buildings and its costs, Viewpoints], Jim Polaski raises alarms about the cost of electrifying buildings in Oak Park. I think he is confusing two different types of electric heating. The old form of electric heating, referred to as Electric Resistance Heating is, indeed, one of the most expensive ways to heat a building. The more recent technology, which involves heat pumps, on the other hand, is one of the least expensive and in recent years has seen such significant improvements that Maine, one of our coldest states, is leading the nation in conversion of homes to heat pumps.

Whereas one can hope for, at best, about 95 percent energy efficiency using a gas-fired boiler, a heat pump can deliver space heating (or cooling) at as much as five times the amount of heating for the input of energy used (depending on whether geothermal heating is included). How does this happen? It is because the electrical energy the heat pump uses is not converted directly to heat, as in the case of a gas-fired boiler or an electric toaster. The electrical energy is used to operate a compressor that moves heat already in the air.

Forty years ago, heating through hot water systems was the gold standard, generally regarded as superior to forced air. Nowadays, however, conversion of a forced-air furnace system to heat pump is easier than for hot water.

I would advise Jim and anybody else concerned with saving money on heating and air conditioning to make a very modest investment in tightening up the air flow through their aged, drafty houses along with ramping up the insulation. That way, when you do decide to replace that boiler or furnace, you will be able to use a smaller heat pump, and in the meantime, you will save money on heating and cooling.

I would add that the village board has turned its attention to electrifying buildings because recent studies of our local energy use has shown that more than two-thirds of our carbon footprint is from energy use of our buildings. Although many of us are investing in electric vehicles, taming the energy use of our buildings should come first.

Nick Bridge
Oak Park

This was originally posted on the Wednesday Journal on 4/2/2024