Battling the cold with new air-source heat pump

I don’t know about any of you, but it’s frickin’ cold in Ontario right now, so it’s this time of the year when we rely heavily on home heating. Ontario is a mish-mash of different technologies: resistance heating, natural-gas furnaces, oil furnaces and propane. Out of them all, the most affordable option is natural gas.

Now, natural gas is okay but it’s not ideal. It still emits greenhouse gases and NOx. It’s also becoming more volatile and is likely to become much more expensive over the coming years. Also, the power mix in Ontario will become cleaner over the next decade — no coal, more nuclear, hydroelectric, wind and natural gas. So there’s an argument that heating your home with electricity could be cleaner than using natural gas, if you can do it efficiently — in other words, if you can find a better way than using resistance heating.

This has many people in Ontario looking at geothermal. But these ground-source heat pump systems are a big gamble — with a big upfront pricetag and half the system underground, if something goes wrong with the installation it’s a major pain in the you know what to fix.

I wrote a story today (companion story here) on Hallowell International, a fairly new company based in Maine, that has developed an air-source heat pump that works in colder climates — i.e. Canada and the U.S. north. Company founder Duane Hallowell, a 34-year-old engineer who was a cryogenics expert with the U.S. Navy, realized that conventional air-source heat pumps that are popular in the U.S. south do not perform well in cold climates and are therefore not economical. So he went ahead and built his own, called Acadia, and it can operate efficiently down to minus 30 degrees C.

Hallowell argues that its system is three times more efficient than resistance heating, but on an annual basis cheaper than natural gas, propane and oil (though the payback on natural gas is longest). In downtown Toronto, where drilling bore holes for geothermal is prohibitively expensive, if not impossible, using an air-source system instead that requires no digging, is nearly as efficient as geothermal, and can provide both heating and cooling is an attractive proposition.

The company still has a long way to go to build confidence in the industry, but Mitsubishi is apparently coming out with its own competing model to Acadia, which is good news. It could be that over the next few years Acadia-style air source heat pumps will pose a major challenge to high-efficiency natural gas furnaces, particularly in densely populated urban areas, and give the gas company pause for thought.