Clean and Green Home Heating

BPEG chair, Rod Layman, shared his work-life experience in HVAC, complete with charts and lots of statistics!

Rod reviewed the pluses and minuses of heating systems, including some new tech and interesting pluses for some of the old tech. Showing a photo of in-floor heating being installed in his Lion’s Head residence, we could see the large thermal mass inside the structure, concrete in this case, working as a heat sink and delivering radiant heat to the entire house. The floor, a dark-coloured concrete when finished, also absorbs sunlight through large south-facing windows, radiating it back as heat — the passive solar effect. When discussing forced air furnaces he stressed that installing fresh filters as critical for effectiveness/economy.

Regarding carbon (CO2) emissions of heating systems, wood burning came in quite favourably since it’s assumed that for every tree burned, a new one replaces it, re-absorbing an equal amount of carbon. Oil furnaces, on the other hand, are the dragon of carbon emissions, with propane coming second. Electric heat in Ontario has low carbon emissions now that coal-fired plants are gone. This is especially true with the use of air source heat pumps and geothermal.

The air source heat pump (ASHP) works like an air conditioning unit in reverse. Better technology is making it a practical and cost-effective heating system. The heat pump unit is a n external box, usually fastened to an outside wall at the back or side of a house, that extracts heat from outside air – even at minus 20C. The heat pump is on average 2.8 times more efficient than electric baseboards. ASHP installation costs are coming down, about $5,000 for a smaller house, and the reduced electricity bills will often pay back this cost in 6-7 years. ASHPs can also provide cooling in summer, and their CO2 emissions are lower than all but wood heating. Geothermal systems are also very efficient but have very high installation costs, 20-40K.