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[at-l] BLM Encourages Wind Power Development
"...The sites cover about 5,000 acres and generate about 500 megawatts of
electrical power per year," claims the Bureau of Land Management press release
supplied to us by TJ.
I'd be more impressed if the report reflected a basic knowledge of electricity.
If I remember my 45-year-old physics, watts (kilowatts and megawatts) are a
measure of capacity. You build capacity. You don't generate it. You use capacity
to generate MEGAWATT HOURS each year. 500 megawatts of capacity is equal to a
typical small generating plant. If they are really talking about 500 megawatt
hours, that is truly a very tiny amount -- enough to power a few hundred homes.
Megawatts are a measure of the ability of the turbines to generate electricity.
When the wind is blowing just right and nothing else hampers the effort, 500
megawatts of capacity will generate 500 megawatt HOURS of electricity each hour.
Of course nature changes minute by minute. Sometimes the full capacity of a
turbine can be used. More often only part of the capacity or none of the
capacity will be generating.
The only useful measure of electricity is megawatt hours, not megawatts. A
natural gas base power turbine will generate in megawatt hours its capacity
times 24 hours a day time the number of days per year it operates. (all are shut
down for maintenance so they don't operate 365 days a year.)
A hydroelectric dam or a wind turbine system with the same capacity will
generate far less energy (kilowatt hours of electricity) each year. Check your
electric bills. You are buying KWHrs, not kilowatts.
In the long squabble over dams on the wild St. John River in Maine, the two
terms were totally garbled. The dams had about the same capacity (megawatts) as
the state's only nuclear plant. Politicians (and newspaper editorials) used the
figures to assume that electricity supplies would double with the construction
of the dams.
The problem was that the river only has significant amount of water during the
spring snow melt. The dams would have created a giant lake that allowed the
storage of this six weeks of flow so that it could be parcelled out over the
year. Rather than doubling the low cost electricity available to Maine, the dams
would have increased the supply by about 10 percent -- and the resulting
electricity would have been the most expensive, so expensive that it would only
be used during peak demand hours.
Sorry for the lengthy explanation, but since TJ brought it up I thought the
explanation worthwhile, considering the wind power project proposed to be
located about three-quarters of a mile from the AT in the Saddleback-Bigelow
section in Maine.