Michael Fumento in Inference:
Wind and solar energy are not becoming competitive with other forms of electricity generation in the United States. Impressions to the contrary are based on flawed data. In its accounting, the U.S. Energy Information Administration (EIA) uses what it calls levelized costs. These represent the per-kilowatt-hour cost of financing, building, operating, and maintaining an electricity generation plant over its assumed financial life.
Levelized costs were designed to permit a comparison between all forms of electricity generation, but data for wind and solar energy, on the one hand, and other sources of fuel, on the other, do not necessarily correspond.
The nameplate capacity of a plant designates its production maximum under ideal circumstances. The capacity factor of a plant, by way of contrast, designates the percentage of its nameplate capacity that it realizes in day-to-day operations. Nuclear has an impressive capacity factor of about 92 percent in the United States, more than double what it was in 1972. This improvement is one of the unsung successes of nuclear power.5 The capacity factors for wind and solar energy are at the opposite end of the scale. According to the EIA, wind averages about 34 percent; the Global Wind Energy Council estimates it at only between 15 and 30 percent.6 The EIA estimates the capacity factor for solar energy at 28 percent; the industry itself gives a lower range of between 10 and 25 percent.7
These are interesting discrepancies between government and industry estimates.
More here.