Oil?

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why we use oil in concentrated solar power why not water

They do not use "oil" in solar plants. A mixture of potassium nitrate and sodium nitrate salts (in their molten states) is used in those plants.

It is used because it provides a better heat retention capacity than normal water. And, let me ask you a question - why didn't you sign your post.and why is it not auto-signed? YogiReallyRoxx!! 17:57, 14 October 2012 (UTC)