Monday, 9 November 2009

Solar Thermal Molten Salt Project For California
05 November, 2009

Rice Solar Energy, LLC, a subsidiary of Solar Reserve, has filed plans to construct and operate a large solar farm in Riverside County, California. The proposed project will have the capability of producing approximately 450,000 MW hours of electricity annually, with a nominal net generating capacity of 150 MWs. The proposed facility will use concentrating solar energy (CSP) technology and while that's nothing new, it will include a molten salt "battery".

Thousands of mirrors, known as heliostats, will focus the sun on a large receiver that contains a salt mixture - sodium nitrate and potassium nitrate. The molten salt will then be routed to an insulated storage tank where it can be stored with minimal energy losses. When electricity is to be generated, the liquefied salt flows through a steam generating system. The salt is then sent to the cold salt thermal storage tank and the cycle is repeated. The stored energy in the salt can be extracted upon demand and produce electricity even when there is no sunlight, therefore allowing for a dependable baseload supply.

Another very important aspect is an air-cooled condenser (ACC) will eliminate water consumption for cooling the steam turbine exhaust. Unlike solar farms equipped with solar panels that use no water at all to generate electricity, water consumption issues have been the centre of controversy regarding solar thermal plants, particularly given their locations are usually in arid areas. The company is negotiating with California electricity companies to buy the electricity generated and expects the solar farm to be operational by October 2013.