Tuesday, September 13, 2005

Energy from Cold Water

I read this article from Wired Magazine a while ago and didn't want to forget about it--hence this post. The article is about how cold water (really the difference in temperature between cold water and hot air) can be used for air conditioning, fresh water generation, and even power generation. Plus, you can use the "side effects" to help grow fruit faster.
Running the frigid pipes through heat exchangers produces unlimited air-conditioning that costs almost nothing. Draining their sweat yields an endless supply of freshwater for drinking and irrigation. The cold water also creates a temperature difference between root and fruit that Craven believes speeds growth. And by turning the flow on and off, Craven has found he can further accelerate the plants' growth cycle by forcing them in and out of dormancy - he can get three crops of grapes a year and pineapples in eight months instead of the usual 18.
And to generate electricity:
Pipes draw warm water from the ocean surface and cold water from the seabed. The warm water enters a vacuum chamber and is evaporated into steam that drives an electricity-producing turbine. The cold water condenses the steam back into water for drinking and irrigation.

Update: Here are some links on Ocean Thermal Energy Conversion (OTEC):