Saturday, February 12, 2005

More beans

According to the U.S. Energy Information Agency, if the renewable production tax credit is extended from 2005 to 2015, there will be 42,000 1.5-MW wind turbines installed in the United States by 2025, covering 3,750 square miles. These windmills would generate 206 billion kilowatt-hours of electricity per year, meeting 3.7 percent of the United States’ electricity demand in 2025.

First off, that production figure represents a capacity factor of 37.3% [206,000,000 MW-h ÷ (42,000 × 1.5 MW) ÷ 365 days ÷ 24 hours]. A more likely capacity factor is 20%, which cuts the projected output almost in half.

Second, 3,750 square miles represents 38 acres per megawatt. This is the low end of the density range for wind facilities, which use 30-60 acres per megawatt. So 42,000 1.5-MW (63,000 MW capacity) could very well take up to 5,900 square miles, larger than all of Connecticut.

A power plant the size of Connecticut to provide 2% of the country's electricity. Brilliant.