By Ian Clark, Special to Financial Post
Natural Resources Canada says Canadian electrical use is 600 terawatt hours (TWh or trillion watt-hours) annually. What few recognize, however, is that we are already over 80 per cent green with respect to carbon dioxide (CO2) emissions. This is primarily due to our abundance of hydro and nuclear power. Nuclear is arguably our greenest source of electricity. It produces essentially no CO2; it has by far the best safety record; and we know how to safely manage nuclear waste. As for wind, despite massive subsidies it currently contributes only four per cent to our grid. It remains intermittent, off-peak and low-grade electricity, only marginally better than solar.
How about big wind? Germany favours wind but has learned that its inconsistency requires baseload backup with coal-fired thermal plants. In Canada, net-zero with wind would require upwards of 300,000 turbines, or 50 times more than we have now, plus an extensive distribution network for this decentralized system, plus an equivalent thermal generation backup (unless we resolve to drive and heat our homes only on windy days).
Offsets by planting trees (also planned in the Mid-Century Strategy) are an illusion once one looks closely at the carbon cycle. The only time Earth experienced a notable reduction in atmospheric CO2 by growing trees was during the Carboniferous Period between 350 and 300 million years ago, when our coal resources were formed. Conversely, the slashing of our forests over the past 200 years and today in the Amazon basin has had no measurable impact on atmospheric CO2.
This leaves nuclear as the only viable option for any plausible net-zero plan. Canada has 19 operating nuclear reactors at four stations, producing 15 per cent of our electricity. Net-zero would require an expansion of this fleet to over 300, operated in about 40 new nuclear power generating stations, and costing upwards of a trillion dollars.
The only sensible option for Canada is to invest our environmental goodwill and dollars where they can have a positive effect, such as for sustainable agriculture, biodiversity and healthy waterways — and into adapting to climate change, for the climate will indeed change. It always has.
Ian Clark is a professor of earth and environmental sciences at the University of Ottawa.