For example: he says that our society can’t rely entirely on wind farm generation because we would have periods with no power. Hence wind is not a silver bullet. Well, who said it is? In the Bush Administration’s 20% Wind by 2030 report, its authors very clearly said that wind turbines can be a significant part of the solution, but no one argued it would do the whole job.
Mr. Zehner’s book suffers from a basic misunderstanding of how the electric power system operates. He seems not to understand the portfolio approach to power generation, whereby a variety of power sources play together to maintain balance between demand and generation. He criticizes wind as not providing base-load power, missing the fact that large sections of the country (such as the electricity networks in Texas, Iowa and Colorado) are successfully integrating wind power at record-breaking levels. For example, Iowa now gets 20% of its electrical energy from wind. When the wind blows, existing fossil-fueled plants are backed off; these same plants ramp up as the wind dies down. But no new power plants are needed to accommodate periods with low winds.
Most electric power portfolios do include large base-load plants–those that operate at nearly constant output levels for long periods. But other plants capable of ramping their output levels up and down often and fairly rapidly are also needed, because the demand for electricity varies with time. Consequently a portfolio consisting entirely of base-load plants could not maintain balance between varying demand and generation. So criticizing a generation option like wind for not providing base-load power makes no sense. Power utilities don’t add wind power to provide base-load power. Rather they use wind primarily to displace the consumption of fossil fuels and the associated pollution.
Moreover, experience with integrating large amounts of wind energy in the U.S. and Europe shows that system-wide changes in wind farm output occur over periods of several hours and can be predicted well enough so power-system operators can accommodate them–particularly when wind farm plants are spread over a large area to take advantage of the fact that wind variations tend to average out spatially.
Mr. Zehner claims no conventional sources have been retired as renewable contributions have grown. Yet adding wind energy to the grid displaces output from the most expensive power plants currently operating, almost always a fossil-fired power plant. As a result, every utility, independent grid operator, and government analysis that has looked at the issue has found that wind energy significantly reduces fossil fuel use and pollution. And in some regions, plans for new coal plants have been replaced with plans to install a combination of wind energy and natural gas plants instead. This trend is likely to continue as air-quality concerns encourage the retirement of older coal plants.
He argues the nation should put its resources into conservation and efficiency instead of encouraging the development of renewable energy, when both approaches are clearly needed to get us through our energy future; you can’t solve this equation just on the demand side. Policy support for efficiency and policy support for renewables aren’t mutually exclusive.
Mr. Zehner attacks DOE’s 20% scenario by asserting that cost savings tapered off after the 1990s. It’s true that costs rose in the early 2000s, but now a whole new generation of cost reductions is emerging with much taller towers, longer carbon-reinforced blades, and improved gearboxes or alternatives.
The bottom line is that Mr. Zehner’s book exhibits a sensationalist tendency to bash wind and seems designed to try to arrest its growth as the number two source of new American electric generating capacity in recent years (second only to natural gas).
When it comes to wind power, Mr. Zehner appears to have some illusions of his own.
By Edgar DeMeo, Renewable Energy Consulting Services, www.awea.org/blog/
