The sky-high prices may seem to run counter to the conventional wisdom that the larger the prospective buyer pool, the larger the chances of attracting multiple bids and driving up the price.

FORBES: Stealth 'Off-Market' Home Sales On The Rise Among The Super-Wealthy

The wind power's cost is as much as twice that of conventional power, but because it would be a small portion of the overall energy pool, consumers would see at most a 2.2% increase to their monthly bills, according to estimates in a 2010 report by Massachusetts regulators.

WSJ: Cape Cod Wind Farm Tiptoes Ahead