This is from the Arizona Republic:
Two decades from now, Americans could get as much electricity from windmills as from nuclear-power plants, according to a government report that lays out a possible plan for wind-energy growth.
The report, a collaboration between Energy Department research labs and industry, concludes wind energy could generate 20 percent of the nation’s electricity by 2030, about the same share now produced by nuclear reactors. Wind energy today accounts for about 1 percent of the nation’s electricity.
To reach the 20 percent production level, wind turbines would have to produce 300,000 megawatts of power, compared to about 16,000 megawatts generated today. Such growth would envision more than 75,000 new wind turbines, many of them larger than those operating today. Turbines in offshore waters would produce about 54,000 megawatts.
I am sure we also could have 3 billion hamsters on little wheels hooked up to generators. Or we could fill, as Al Gore wants, 5 million acres of Arizona desert with solar panels. Of course I calculated the latter plan to cost about 20 trillion dollars.
Just because the megawatt numbers add up to some target, does not make it a feasible plan. The cost per megawatt needs to be balanced against other potential sources of power, and technological deficiencies (e.g. no solar at night, no wind power when there is no wind) also need to be addressed.
there are some massive holes in this plan.
first, 300mw from 75,000 turbines implies 4mw/turbine. this is utterly unrealistic. the largest wind turbine ever constructed was 6mw (and had blade diameter of 126 meters and was 200 meters tall). imagine trying to site 75,000 of those.
don’t even get me started on where you would get the carbon fiber for the blades for all these wind mills. world production could not be ramped to 10% of this, and doing so would necessitate massive investment in acrylic precursor production that is a nasty, polluting industry.
assuming through some miracle you could build and site all these turbines, you will get nothing like 6mw from them. average output for an efficient and well sited wind farm is about 20% of rated capacity. so, they are going to put out an average of 1.2mw, and will miss the forecast 4mw by 70%. oh, and good luck finding proper siting for this many massive windmills.
worse, the output will be unpredictable. having 20% of your energy grid run on something like wind that can and will arbitrarily stop frequently is ludicrous. this amount of power cannot be stored.
adding to the problem, wind tends to be highest at sunrise and sunset. this does not coincide with peak power, which tends to come in the early afternoon on a hot day as everyone runs their AC. wind tends to be slowest at such times.
so you will still need nearly all of the baseline grid power stations you had before to cover the peak periods.
trust me, if you think solar is expensive, try wind.
Also worth considering is the sort of thing well demonstrated by the youtube item at
http://www.youtube.com/watch?v=7nSB1SdVHqQ
Definite oops, and, of course, they would need to be sited far enough apart to prevent the flying bits from hitting another windmill. I have to wonder why the vertical axis type of windmill is not used more often. Sure, there are some engineering problems, but so are there with the horizontal axis models (see above link!). More to the point, the savonius type mill can accept wind from all directions without the need to track into the wind, consequently can be more efficient. But we’re still back to windless times needing back-up from some other source.