But some experts say that continual increases in energy supply -- whatever the source -- are not the optimal response to the climate crunch. They say the answer is not more energy but much more efficient use of existing energy.
According to data compiled from a variety of utility and government sources, the proposed new dams will boost Canadian hydro capacity from 74,000 megawatts -- which ranks us third in the world -- to about 88,500 megawatts.
Of the added capacity, the most is in Quebec 4,570 MW, followed by B.C. 3,341 MW, Labrador 3,074 MW and Manitoba 2,380 MW.
Major projects in the works across the country include the Site C dam in B.C. $7.9 billion, three Manitoba dams $14.9 billion combined, three Quebec dams $11.5 billion combined, and the Muskrat Falls dam in Labrador $6.2 billion.
Much of the new power will be exported to the U.S., especially in the earlier years of these dams before domestic demand catches up.
The resurgence in hydropower is linked to the Canadian hydro industry's effort to market its product as an answer to global warming. Hydropower is "a very strong climate change solution," said Jacob Irving, head of the Canadian Hydropower Association CHA, which represents industry interests. The argument, as stated in a recent CHA document, is that "each terawatt hour of hydro exported to the United States largely replaces fossil fuel generation." It says such exports already reduce continental greenhouse gas emissions by "at least half a million tons" annually.
An additional advantage of hydropower is that it enables utilities to add a greater proportion of intermittent renewable energy sources, like wind and solar power, to their generation mix. Unlike most energy sources, hydro can be turned on and off almost instantaneously, and that makes it ideal for "filling] in the gaps from intermittent sources," Irving said.
The argument for increased hydro exports is compelling, especially given that each year 600 coal-fired generating plants in the U.S. burn nearly a billion tons of coal, the worst form of energy from a climate perspective. Those 600 plants account for almost half of U.S. electricity generation only 19 per cent of Canadian electricity is from coal. Another 24 per cent of U.S. supply comes from natural gas-fired plants, which are roughly half as bad in terms of emissions.
But John Bennett, who heads the Sierra Club of Canada, said "we waste half the hydro we produce" because we lag behind in energy conservation and efficiency. He believes the "major investment" should be in these areas. The solution to climate change, he said, is "to use less energy," not to build more mega-projects that increase supply.
Ralph Torrie agreed that cutting energy consumption in half is both necessary and possible. "If you want to see how it's done just take a vacation to Europe," he said. Torrie is an internationally recognized energy expert and the Managing Director of the Vancouver-based Trottier Energy Futures Project. He advocates reducing energy demand through the use of more efficient means -- often existing technology -- to meet virtually all the needs electricity serves.
Unlike Irving, who accepts the standard predictions that electricity consumption in Canada and the U.S. will grow by about one per cent annually in the coming decade, Torrie advocates a "new way of thinking about the energy future."
This new way treats conservation as a resource: "There's almost always a kilowatt of electricity that can be saved for a smaller cost than building the ability to generate a new kilowatt," Torrie said. Plus, the resource gets bigger with every new innovation in efficiency.
Most Canadian utilities tout their efficiency and conservation measures. Irving said "energy conservation has to be forefront of all decisions." But how do conservation efforts compare to the resources allocated to building new dams? Montreal-based energy consultant Philippe Dunsky said total spending on efficiency and conservation programs in Canada is only about $1 billion annually.
If dams are included in a North American response to climate change -- which seems inevitable -- Bennett said they must be in the context of a clear, broader plan to reduce emissions. Dams do not reduce emissions per se -- they increase supply -- so they have to be "part of a bigger scheme." But no such bigger plan exists, Bennett said, and emissions in both Canada and the U.S. remain above 1990 levels, the benchmark set in the Kyoto Accord.
Meanwhile, the U.S. Energy Information Administration predicts that in the absence of policy change, the use of coal generation will continue to increase over the next 25 years.
Canadian utilities argue that hydro exports displace coal generation. Hydro Quebec, for instance, reports that its exports "avoided emissions of 9.05 [megatons of carbon dioxide]." But critics can say that every additional kilowatt of cheap power simply postpones the ultimate necessity of addressing inefficient use of electricity and run-away energy appetites. Both arguments have merit. If policy makers rest only on the coal displacement argument they do so at considerable peril.
Without a concerted effort to tame demand, increased hydro generation will simply be matched with increased coal consumption and increased global temperatures. That begs the question: can hydropower be part of the climate change solution if no such solution is in the works?
At some policy makers must make conservation the dominant priority. Ideally, this will happen before all the rivers are dammed and all the coal is vapourized.