Friday, February 02, 2007

Construction on Mars Hill, Maine


The tower height of these GE models is 262 feet, so it appears that the flat circle is at least 270 feet across -- almost the length of a football field -- or about 1.3 acres. The cut-and-filled area looks like another 3 times that, so the total physical footprint -- not counting the roads, transmission line rights of ways, and substation -- is at least 5 acres. This is repeated every 750 feet (about 7 per mile). The loss of interior forest habitat extends 250 feet farther from the edges, for a total loss of about 20 acres.

The loss of absorptive ground cover and the effects of roads is likely to cause severe run-off problems, including the silting up of brooks, a lowering of the water table, and even alteration of underground water flow -- serious problems where most people rely on wells for their water.

And that's just the surface. There's dozens of tons of concrete and rebar underneath the each tower, and, according to an Oct. 28, 2006, article in the Bangor Daily News, for the dozens of 2-1/2" rock anchor bolts holding the base of the tower "workers drilled 45 feet into the ground, made sure they had hit bedrock, grouted the bolts into the ledge, and then made sure they could withstand about 400,000 pounds of force."

The Mars Hill machines have a maximum generating capacity of 1.5 MW and a total height of 328 feet. The possible Clipper models now proposed for Sheffield and Sutton have a capacity of 2.5 MW and a total height of 418 feet. That means they will need even more space and more anchoring.

More pictures of Mars Hill can be seen at National Wind Watch.
Documentation of the destruction of Cefn Croes in Wales is also available.

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