COMPARING WIND AND NUCLEAR ENERGY

So how does offshore wind stack up to nuclear?

Moody's Investors Service, commenting in May about the rising cost of atomic power, said the potential cost of a new plant being proposed today is more than $7,000 per kilowatt of capacity. This equates to about $5.3 billion for every 750 megawatts of nuclear capacity added to the grid.

Helimax estimates that the average cost of offshore wind development in Ontario is about $3,800 per kilowatt, or $2.9 billion for 750 megawatts of offshore wind capacity – that is, a project the size of what Trillium has proposed.

Such a comparison, however, is misleading. The lifetime "capacity factor" of Candu nuclear reactors around the world is about 80 per cent, a figure some would call generous in the Ontario context. This means the reactors have produced energy on average that amounts to 80 per cent of potential capacity. Helimax said offshore wind turbines have a capacity factor ranging from 35 to 40 per cent.

So to get the same energy over the course of a year from an offshore wind farm you'd have to build twice as much. This makes offshore wind slightly more expensive than what Moody's is predicting for the cost of nuclear. But is it really? Offshore proponents are quick to point out that with wind power you don't need a lifetime supply of uranium fuel, don't produce toxic waste products, don't have to pay for long-term storage of those waste products, and have lower ongoing staffing and maintenance costs.

They acknowledge offshore wind isn't baseload power like nuclear. Then again, there's no risk of a 1,500-megawatt reactor shutting down for a month or two in the summer because of unscheduled maintenance, like we saw last summer at Pickering generating station.

Timing is also an important consideration. Ontario's first lake-based wind farms, should the province choose to go down the offshore path, could be built and operating by 2013 – a year before the last coal plant is scheduled for shutdown in Ontario. The new nuclear plant at Darlington, as much as the province may need it for baseload power, won't go live until 2018.