If this report from Watt's Up With That? is indicative, it's apparently about five years when they're exposed to high winds and salt spray. This is about 20% of the rated life.
Regarding that rated life, having done defense related contracting, suffice it to say that I'd be surprised if they'd done a good statistical analysis involving salt spray, waves, winds, UV light, and the like....in other words, their analysis was almost necessarily flawed. However, any good old time engineer--the kind they might not like hiring at renewable energy companies for obvious reasons--would have told them that they're going to have difficulty due to these factors.
And given that you've got to anchor them somehow--either a floating platform or a foundation going to the bedrock under the sea--it also isn't entirely clear that they're going to produce enough energy to justify making them.
Ouch. Once again, "environmentalist" all too often means "person who cannot do math or science." H/T Powerline.
The Two-Income Trap - The Two-Income Trap: Why Middle-Class Mothers & Fathers are Going Broke, by Elizabeth Waren and Amelia Warren Tyagi. Published in 2003. Hardcover, 272 page...
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