Andasol - World's Largerst Solar Power Plant So far Powers Up - 2012 January

3 Jan 2012

It is a 150 megawatt plant built with an investment of 350 million euro in Spain.

Still bigger plants are in pipeline.

An international venture called Desertec Industrial Initiative has recently announced plans for a Sahara-wide, €400 billion solar energy project, starting in the region of Ouarzazzatte in Morocco in 2015.
Desertec’s plans could produce 15 per cent of Europe’s electricity by 2050.

http://www.timesofoman.com/featuredetail.asp?fid=1533

Molten salt to store excess energy during the day and give it back durng the night is being used in Andasol plant.

http://www.scientificamerican.com/article.cfm?id=how-to-use-solar-energy-at-night