Wonder how much heat the mirrors produce at the solar receiver ?.
Check the comments...think I saw some links that might help.
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The receiver, which is a radiant forced circulation steam boiler located at the top of the DPT, will convert water to superheated steam at temperatures up to 565 degrees C. The pressurised steam will then power a Rankine-cycle reheat steam turbine with excess passing to a reheat tower adjacent to the turbine. Additional heliostats will be located around the perimeter focusing on the reheat tower, which will allow a prolonged generation period when the sun is not shining.
Each power plant will also include a partial-load natural gas fired steam boiler to assist the plant in coming up to operating temperature more quickly in the morning. These boilers will also be used during transient cloudy periods to maintain the turbine on-line and ready to use.