EDMONTON - It's official: The glorious future of abundant free energy has been put on hold. In May, the Alberta Electric System Operator (AESO) announced that the province's grid could not safely accommodate more than 900 megawatts of wind-power generation, a target that will be met late next year. Proposals for 3,000 more MW of production have been thrown into indefinite limbo at an estimated cost to producers of $6-billion; meanwhile, the province is already spending $1-billion to strengthen the transmission system so that even the 900-MW cap can be reached. In Ontario, meanwhile, the grid operator warned late last month that 5,000 MW -- about one-fifth of the province's current peak consumption -- is probably the absolute technological limit. (A total of 1,280 MW of wind capacity is already in operation or being built.)
It is starting to look as though wind cannot meet more than a fraction of our energy demand even if other issues with the technology, like esthetics and wildlife impacts, are ignored. The problem, as engineers skeptical of wind power have been yelping for decades, is that power usage and production constantly have to be balanced in an electrical grid. Adding too much unstable, unpredictable power to the system creates a risk of failure and cascading blackouts. In fact, the EU is investigating the possible role of Germany's heavy wind-dependence in causing a Nov. 6 blackout that hit 10 million Europeans.
The depressing corollary is that even in reaching the modest limits now being laid down by the grid police, Alberta and Ontario are relying implicitly on the relative sluggishness of their neighbours in adopting wind technology, using interconnections with other provinces and states to off-load excess power and cover shortfalls. So the system operators' warnings aren't just a sign that wind has reached a dead end in their home provinces. They also mean that B.C., Saskatchewan and parts of the U.S. Northeast will never be able to get major wind projects off the ground if they are to continue to serve as an energy release-valve for their wind-harnessing neighbours.
The windustry has met the announcements with its usual optimism, pointing out that existing wind installations could be made to co-operate better with the grid if improved region-specific wind forecasting existed. But even assuming such a thing can be wished into existence, predictability is not the same thing as stability. During low-wind, high-demand periods, a drop in output still must be made good by other power sources. Since a nuclear pile can't be switched on and off like a light bulb, Ontario's hydroelectric output is already taxed to the limit and Alberta doesn't have much hydro, guess what technology steps in to fill the void? That's right -- good old Stone Age hydrocarbon burning.
This wouldn't be such a big deal if wind output were naturally synchronized with patterns of maximum power usage. But a report released last Wednesday by Energy Probe, Ontario's independent power think tank, confirms another longstanding taunt of the wind skeptics: Wind is often utterly out of sync with human activity.
Energy Probe's analysis of hour-to-hour capacity factors at Ontario wind farms shows output declining disconcertingly in the morning, just when we greedy energy hogs are getting out of bed, turning on appliances and lights, and going to work. On a month-to-month basis, data from this summer show wind output remaining flattest during the hottest periods. And the AESO has found that in Alberta's southern wind corridor, the turbines spin like crazy when the chinook is blowing and little electricity is needed; in the still air of serious cold snaps, when loads are high, the turbines grind stubbornly to a stop.
The overall result is that much of the theoretical environmental benefit from wind power cannot be realized, especially since the generators that must remain on standby to provide emergency "ramping" tend to produce more pollution per watt than round-the-clock coal and gas facilities.
But at least it's still economically free energy, right? Well, maybe. As an internationally observed rule of thumb, wind farms are expected to deliver, on average, 30% of their theoretical maximum power output. On the basis of partial data, Energy Probe expects the three major farms in its study to come in at 24%-27% over a full 12 months. And that's not even including the showpiece Windshare turbine at Toronto's CNE, which delivered a mean capacity factor of just 14.7% in its first 42 months of operation.
It must be a harrowing time for those who once thought the cool breeze could save us all from the coming ecocide. The expectations of wind advocates have already had to be minimized as they realize there is nothing inherently virtuous about their pet piece of tech. Alas, like recycling fanatics, they are likely to end up praising wind power as a moral enterprise that "instills good habits" and signals "green consciousness," even if the honest cost-benefit analysis goes against them in the long run.
colbycosh@gmail.com
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