Oops!

Here's a fact that is new to me: wind farms have a useful life span of 20 years (more or less). The picture is of a wind farm being decommissioned in Wisconsin. Other energy sources have longer life spans like 50 years for a natural gas power plant or 60 years for a nuclear plant.

You didn't ask but I have a background in finance and capital allocation for corporations. The accounting rules say an asset is depreciated over it's useful life like 20, 50, or 60 years. The monthly depreciated cost is the division of the item's cost by the useful life. So what? Power sources should be depreciated over their useful life. U.S. government practice seems to be to depreciate them all at 30 years and this makes wind look cheaper than it really is and gas and nuclear more expensive.

Check out this article at PowerLine for details. It has a link for even more information.