According to the Environment Canada report Climate Change Plan for Canada, 28.7% of personal greenhouse gas emissions are from space heating, compared to 49.9% from transportation. Since there are many more vehicles than there are household furnaces/boilers, this means that the average household furnace/boiler produces more ghg’s than the average vehicle.
Personal ghg emissions
If you want to determine more accurately how many ghg’s you produce and how many are from space heating, you can visit one of the many online carbon calculators. According to the carbonzero.ca calculator (linked to by davidsuzuki.org), each GJ (which costs 7.84/GJ including delivery from FortisBC as of August 2020) of natural gas you consume produces 0.05 tonnes of CO2, each 10 litres of pump gas you consume produces 0.027 tonnes of CO2, and each GJ (equivalent to 277.8 kWh) of electricity you consume produces 0.01 tonnes of CO2. So, this means that at prices of $14.33/GJ for natural gas , $1.45/L for pump gas, and 6.55cents/kWh (17.08/GJ) for electricity, each dollar you spend on natural gas results in the same ghg emissions as each $3.42 you spend on pump gas and each $11.60 you spend on electricity.
When upgrading from a low natural gas furnace/boiler to a mid or high efficiency unit, you will decrease your ghg’s by one percent for every one percent you decrease your fuel usage. If you go with a heat pump, you can decrease your ghg’s even more. A heat pump runs off of electricity and emits no emissions, and since electricity is cleanly produced in BC mainly by hydro, you can reduce your heating ghg’s to a fraction of their current levels by installing a heat pump. If you are heating your house with a 300% efficient heat pump, with only one-fifth as much ghg’s produced consuming a GJ of electricity as a GJ of gas, then you are only producing about 1/25 of the ghg’s which would be produced by a 60% efficient furnace.