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View Full Version : Wind Power From the Ocean (With Help from Space)



Fraser
2008-Jul-09, 06:50 PM
I drive regularly through Iowa and southern Minnesota in the US, and over the past few years wind farms have been popping up in that region up almost faster than corn grows. These massive wind turbines are awesome to see. But there may be an even better location for future wind farms than [...]

More... (http://www.universetoday.com/2008/07/09/wind-power-from-the-ocean-with-help-from-space/)

JohnBStone
2008-Jul-09, 10:39 PM
There are a _lot_ of assumptions in there, not least the state size areas of land or shallow-sea-shelf area you would have to set aside to get 10-15% of national/global energy output.

Those off-shore windy spots typically have to be in shallow seas (tens of yards) and within a reasonable transmission cable distance of land (tens of miles) and they aren't likely to be anything like enough for the 10-15% mentioned by themselves. Oddly they also don't have to be too windy as current wind-turbines have to shut down above about 60 mph to prevent damage (engineering limits).

There is also the issue that wind is sporadic over large areas so you either have to marry that with new untried demand management techniques and/or also invest in storage technologies (with conversion losses) and/or you have additional reliable base load stations (nuclear or fossil fueled) to make up the gap when the wind isn't blowing.

But offshore wind power is one of the few practical and economic methods we know works. So definitely worth going for, with eyes wide open to the issues.

Unfortunately as mentioned solar electric technology just isn't generally economic or large scale as yet. One to watch out for with desert based based solar farms.

There is also a misunderstanding about availability and generation in the original article when it states that solar generates one kilowatt per square meter. That is the available solar energy per square meter _not_ generation as typical solar panels can only harvest 10-20% of this at noon on a sunny day and of course nothing at night. Predicted energy generation from desert solar farms is 10-20 watts per square meter on average for current technology (that's per unit land not per unit panel as there are significant gaps between panels or concentrator dishes to allow follow the sun tilting without overlap).

Typical wind farm outputs are around two watts per square meter for land and three watts per square meter for offshore (with significant gaps between windmills to allow follow the wind direction rotation).