If you needed to provide power to the Lehigh Valley using windmills alone, how much space would be needed? Take the LV area in which all communities combined is around 300,000 people and figure out the number of windmills need to generate energy for 300,000. The space required to provide energy to an area of 300,000 would be 110 miles!
I love it when Obama speaks of new energy technologies like the windmill. New? They have been around for hundreds of years. The internal combustion engire is "newer" technology than the windmill. Just another example of Obama's historical illiteracy.
The freakin' sun is even older but...
Let's take a 500-megawatt power plant which by itself can power a city of 300,000. (A megawatt is one million watts.) It will sit astride a fairly large plot of land. A coal-fired plant near me is just under that capacity (495 MW) and sits on about 300 acres. Most of that land, however, is essentially devoted to undeveloped transmission right-of-way filled with ponds, woods and streams. Only a small portion is covered by plant facilities including coal storage. I estimate less than 30 acres.
For new wind projects huge 5-megawatt wind generators are just now being deployed. If we take these as typical (and they are not), then using an estimate of the direct land footprint for wind towers of 0.38 acres per tower, we find that we'd need 100 towers covering 38 acres. But wind turbines run at only about 30 percent capacity because the wind doesn't blow all the time. This compares to about 70 percent capacity for coal-fired power plants. So we need to multiply 100 towers by about 2 1/3 to get the number of towers we'd need to match the operating capacity of one coal-fired plant. That means we'd need about 233 towers with a direct land footprint of 87 acres. That doesn't seem too bad. And, the land under the turbines is still available for farming and other purposes. The overall direct effects on the land and water are certainly less when compared to the coal plant.
But we're not done. The spacing between towers is typically at least five diameters of the rotor. That doesn't sound like much. But for the 5-megawatt towers in this example, the spacing would be 2,065 feet times 232--we don't need to separate the last tower from another tower beyond it. Then we'd add the diameter of the rotors--413 feet times 233--and we get a distance equivalent to about 110 miles. So, we'd need a line of 5-megawatt turbines stretching 110 miles. In theory, we'd want to split them up and put them in various locations in which the wind blows hardest at different times. But the total length of the line would still be at least 110 miles. If we take the largest separation recommended between towers which is 10 diameters of the rotors, we'd have to just about double that distance.
By comparison most people who live 110 miles from a coal-fired power plant are rarely even aware that it might be a source of electricity for them. And, the plant is certainly not a direct irritation. The lesson here, however, is not one of aesthetics. It is an illustration of the disparity in power densities between those energy sources on which we currently rely and the alternatives now being proposed and deployed.
The power density problem for solar energy is no less daunting. Vaclav Smil, who has investigated the power density problem carefully, described it this way:
[I]n order to supply a house with electricity, photovoltaic cells would have to cover the entire roof. A supermarket would require a photovoltaic field roughly ten times larger than its own roof, or 1,000 times larger in the case of a high-rise building.
When we contemplate renewable energy sources, we rarely contemplate the land area required to deploy them. Just the problems involved in obtaining rights-of-way alone are beyond anything we've ever experienced. And, the enormous scale of manufacturing required to produce the panels and wind towers would dwarf our current energy industries. The coal-fired power plant by comparison seems like a wonder of compact energy generation.
I am not arguing against solar or wind-generated power but this idea of our energy needs being met with wind and the sun is ridiculous.
Kurt Cobb wrote the article and below is the link from SCITIZEN.
Read more here.
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