Thursday, August 27, 2009

VPIRG calls for 1,000 megawatts of wind

In their new report, "Repowering Vermont", the Vermont Public Interest Research Group outlines how the power from the Vermont Yankee nuclear plant can be replaced.

Mostly, they see us buying more from Hydro Quebec, New York, and the New England pool for about 10 years, while keeping demand growth down by stepped-up efficiency measures.

Then, depending on subsequent growth, VPIRG suggests that by 2032, 25-28% of our electricity can be generated by in-state wind turbines.

They dramatically misrepresent the physical reality of such a program, however.

One scenario calls for wind to provide 25% of 6,300 gigawatt-hours (GWh) in 2032, the other 28% of 8,400 GWh. VPIRG says these would require 496 megawatts (MW) and 766 MW, respectively, of installed wind capacity, using 24 and 39 miles, respectively, of mountain ridgelines. In each scenario, 66 MW of the installed capacity would be small residential and business turbines.

Their estimation of miles of ridgeline required is based on placing 6 turbines per mile. But that figure is based on 1.5-MW turbines, not the 3-MW models VPIRG assumes. Larger turbines require more space between them (Vermont Environmental Research Associates, whose work VPIRG cites, spaces the turbines by 5 rotor diameters: as the turbines get bigger, so does the space between them). A better figure for estimation is 10 MW capacity per mile. The results are 43 and 70 miles for the two scenarios.

Then their translation of energy production to capacity is based on a 35% capacity factor. That is, for every 1 MW of capacity, they project that the turbines would produce at an average annual rate of 0.35 MW, and over a year the energy produced would be 0.35 MW × 8,760 hours = 3,066 megawatt-hours (MWh).

But the average capacity factor for the U.S. is only 28%, and that of the Searsburg facility in Vermont is only 20%. It is typically less than 10% for small turbines. So it would be reasonable (and still overly hopeful, especially as this degree of building would require siting in less productive locations) to assume a 20% capacity factor. Thus, the two scenarios would actually require 835 and 1,316 MW of installed wind.

And that would require 75 and 123 miles of mountain ridgelines (plus 116 MW of small turbines not on ridgelines). Vermont is only 60 miles across through Montpelier and 160 miles long.

Finally, VPIRG completely ignores the impacts of new heavy-duty roads, transformers, transmission lines, and several acres' clearcutting of forest per turbine.

Let alone the noise and light pollution and the aesthetic (and moral) dissonance of 400-ft-high industrial machines with 150-ft-long turning blades (a sweep area of 1.5 acres) dominating formerly wild and rural landscapes.

All for a technology that is only an expensive add-on to the grid and actually replaces nothing.

Vermont Yankee ought to be shut down, but it is ridiculous to pretend that wind can or should fill any significant fraction of the resulting gap.

(Oh yeah: VPIRG's treasurer is Mathew Rubin, wind developer manqué, and one of the trustees is David Blittersdorf of Earth Turbines and anemometer maker NRG Systems -- both of which companies are advertised, without any conflict-of-interest note, on page 23 of VPIRG's report.)

wind power, wind energy, wind turbines, wind farms, environment, environmentalism, Vermont