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SW: fact correction
{{#badges: Climate change |CoalSwarm}}
'''Thermal solar power''' is electricity that is generated from the heat of the sun. The most common usage of solar thermal energy is for on site water and space heating. However, electrical energy has been reliably produced by concentrated solar power arrays. The concentrated solar power method of energy generation has arrays of parabolic mirrors focusing light onto pipes of wateror other heat tranfer fluid. The hot water is heated to the boiling point and powers a steam turbine to generate electricity, or is preheated for use in fossil fuel based generation. <ref name="SciAm">Ken Zweibel, James Mason and Vasilis Fthenakis, "[http://www.scientificamerican.com/article.cfm?id=a-solar-grand-plan A Solar Grand Plan: By 2050 solar power could end U.S. dependence on foreign oil and slash greenhouse gas emissions]," ''Scientific American Magazine'', January 2008.</ref>
The chief resource required is large tracts of land with good sun exposure. Areas with arid land not suitable for farming could be readily cultivated as solar farms. <ref name="SciAm"/> The most profitable sites would be ones near to existing high voltage lines or to major consumption areas such as metropolitan areas or energy intensive industry.
The chief problem associated with this form of electricity generation is that it stops generating electricity when the sun is down. One solution is molten salt thermal storage. During the day, heat from the water is transferred to insulated chambers filled with molten salt, which retains the heat well. This thermal energy method of storage is more efficient than storage of electrical power. At night time, the heat batteries are used as a thermal source for power generation. <ref name="SciAm"/>
"Cost Compared to Coal Fired Power" Currently, coal power is seen as cheeper to cleaner or more renewable sources of power. the Standard and Poore chart cited in<ref name="KhoVen"> "[http://www.khoslaventures.com/presentations/CoalThinkOutsidethePits.pdf The War on Coal: Think Outside the (Coal) Pits,]," Khosla Ventures, 2007 (PDF file).</ref> lists the average baseline cost for pulverized coal at 5.8 cents per kilowatt hour (c/kwh), or the more realistic cost of coal power generated from Powder River Basin (PRB) coal, a coal which usually has fewer contaminants and therefor somewhat bypasses the sulfur caps on coal fired generation, is priced at 6.8 c/kwh. By comparison, the same chart lists wind at 7.1 c/kwh (while noting shortages and energy transportation factors are not included) and concentrated solar (CSP) at between 7 and 11 c/kwh.
