The Pocket's Retrofit Coach, architect Paul Dowsett, responds to Katie McGinty's TED Talk on decarbonizing buildings
Katie McGinty is right - but skirts around one major issue.
Katie says: “[Buildings] represent the biggest growing piece of electricity and consumption demand in the world.” - and yet, neglects to remind us that electricity, in and of itself, is not the bad guy.
The issue should be how the electricity is created.
Are fossil fuels, like coal, coke, oil and natural gas (which is really just methane) being burned, emitting greenhouse gases (GHGs) to create that electricity?
In the US, where Katie is speaking from, this is almost universally true. So in the US, reducing electricity use does reduce greenhouse gas emissions.
In Canada, the sources of our electricity generation vary widely from province to province.
At one end, we have Alberta with 87% of their electricity produced from the burning of fossil fuels. Saskatchewan is at 83%, Nova Scotia 77%, and New Brunswick 40% - so these 4 provinces really need to clean up their electricity grids.
At the other end, we have PEI with only 1%, BC and Quebec at 2%, Manitoba at 3%, Newfoundland & Labrador 4%, and Ontario 6.2%, which is natural (methane) gas used at our peak times. So we must be mindful of this and do everything we can to get our province to reduce natural (methane) gas plants in favour of clean, renewable electricity.
(Most of Ontario’s electricity comes from nuclear - which is another can of worms.)
Generally speaking, in these 6 provinces, we can use all of the electricity that we want, so long as it is produced cleanly.
At the individual home level, electrically-efficient air source heat pumps (ASHPs) are popular in Nova Scotia because most homes are heated with expensive oil or with expensive and electrically-inefficient electric resistance coils (like baseboard heaters).
From a GHG emissions point of view, switching to ASHPs in Nova Scotia reduces their dirty electricity consumption by about 2/3. This is good, but not great.
Here in Southern Ontario, most of our homes are heated by burning natural (methane) gas right in our homes. Whereas this is actually more efficient - by a factor of 3 - than burning natural (methane) gas to produce electricity then using that electricity to heat our homes, we would massively reduce our GHG emissions by switching to electrically-efficient ASHPs, being mindful of the fact that we still need to reduce our electricity consumption as much as possible to not depend upon natural (methane) gas-fired plants to produce the electricity that we need.
So, yes, Katie is right. But the reasons why she is right vary in nuanced ways across North America, and especially across Canada - even within Ontario - between Southern, Central and Northern Ontario.
Clean electricity from renewable sources is good, whereas dirty electricity from the burning of fossil fuels (coal, coke, oil, natural (methane) gas, etc) is bad.
Where to concentrate our efforts on energy efficiency?
If fuel-switching to clean, renewable electricity is the goal, then let’s not worry about lighting and air-conditioning.
First, both are already all-electric.
Second, in our average overall household energy demand, they use 4% and 2% of our annual energy.
Whereas, our predominantly natural (methane) gas driven space heating uses 66%, water heating uses 17%, and cooking uses 11%. This adds up to a whopping total of 94% of our energy used for heating things - and for this, we mostly use natural (methane) gas.
To paraphrase Pocket Change Project Chair David Langille, let’s concentrate on getting off the gas!
Look sharply at your furnace, your water heater, and your gas stove!!
The rest is a distraction …