BEN LUCE – Published: October 28, 2010
The Herald’s recent editorial “Harvesting the Wind” gave some fair acknowledgments of problems with utility-scale wind in Vermont, but concluded that “wind projects will not overrun Vermont” and “if a few more sites were developed in places where environmental damage was kept to a minimum, wind could provide a significant chunk of Vermont’s energy portfolio.”
Unfortunately, the editorial contained a key technical error, upon which these conclusions appear to be founded: It stated that “The Lowell project would produce 63 megawatts of power. That’s about one-tenth of that produced by the Vermont Yankee nuclear power plant.” This estimate neglected to factor in the so-called “capacity factor” of wind generation, which is crucial when comparing wind generation with other energy sources.
Utility-scale wind projects, at best, will only produce about 33 percent of the electricity they could if the turbines produced at peak output all of the time, and possibly significantly less in Vermont. The Lowell project will not in fact produce 10 percent of Yankee, but actually only about 3 percent at very best.
It follows from this that Vermont absolutely will be overrun with wind generation if we try to produce a significant amount of power from this source. Just to produce 20 percent of Vermont’s relatively small electricity load, for example, which is a minuscule fraction of the Northeast’s electrical demand, all 10 of the major projects proposed so far, including those that have been put on hold (such as Ira), or similar projects at other sites, would be needed. If such projects could produce 100 percent of the time at their rated output, then perhaps the editorial’s conclusions would be reasonable, but this is just not the case.
Looking at the problem more broadly, it turns out that utility-scale wind generation sited on virtually all of the windy ridges in the Eastern Seaboard would produce only a few percent of the Eastern Seaboard’s power demand. This indicates clearly that, unlike wind resources in the Great Plains or off shore, ridge line wind in this region is not a serious renewable energy resource. More ominously, it also indicates that trying (vainly) to make it so will incur incredible devastation to our wilderness in the U.S. Despite this, the power industry is fully gearing to build new power lines to Vermont and Maine to extract as much wind power as possible for the East Coast.
The editorial also concluded that “every option must be pursued. Solar, biomass, hydro and conservation are essential. But every source has its drawbacks.” From a resource standpoint, though, it is not the case that every option must be pursued. Even factoring in the efficiency of photovoltaic generation today, the solar energy resource of Vermont is a whopping 500 times larger than the wind resource. Secondly, the “drawbacks” of solar generation in Vermont, in terms of the real impacts to Vermont’s environment and character, are negligible in comparison with wind development. Less than 6,000 acres of solar collection would be needed to fully power Vermont.
Most of this could in fact be sited on rooftops, or on small pole-mounted systems in people’s backyards, or in “solar orchards,” with no clearing, blasting, power lines, noise, impacts to wildlife, or endless rows of 500-foot towers on top of mountains with incredibly distracting, spinning wind rotors.
It is true that wind power is currently somewhat cheaper than solar power. I say only “somewhat” here, because on-site solar generation competes with retail electricity costs, whereas wind power competes with wholesale electricity costs, and on this basis the cost increment to consumers for wind power in Vermont, which is relatively expensive at 9-12 cents per kilowatt-hour, is only slightly less than the cost of solar. But solar is coming down rapidly in cost, much faster than wind power in fact, and is widely projected to be competitive with retail rates by 2015.
Moreover, Vermont is fortunate to have the opportunity to keep the small fraction of its greenhouse gas emissions associated with electricity very low by purchasing hydropower for the time being (which is also cheaper than wind power). So why not then focus now on reducing the true sources of most of Vermont’s greenhouse gas emissions, heating and transportation fuel, and phase in more appropriate sources of renewable electricity as they become more affordable in the near future? This would be a truly rational and appropriate energy policy for Vermont.
Ben Luce is a professor of physics and sustainability studies at Lyndon State College.