The Gemasolar plant in Spain is amongst the frontrunners for the type of renewable energy technology that is set to replace coal based power stations with clean alternatives, and being able to be installed in the arid region of nations are the perfect foil to conventional polluting sources.
This video explains a bit of the functioning of the plant.
Amongst the world’s first commercial-scale concentrated solar power plant (CSP) using molten salts receiver technology, heat is generated using 2,650 large mirrors (heliostats) reflecting the suns rays to a receiver on top of 450-feet tower which reduces the amount of piping and other issues that other technologies face due to their complexity.
The stored energy in the molten salt releases stored energy for approximately 15 hours without the sun shining, providing enough power for 1,00,000 homes.
The receiver heats the salts to enormous temperatures of 500+ degrees, when the molten liquid is pumped up the tower to soak up the sun’s heat directed to the receiver. The energy-storing salts are a combination of 60% sodium nitrate and 40% potassium nitrate and are always in a liquid form.
Each pound or kilogram of molten salt is able to store up to three times the amount of energy that can be stored in oil, an energy-store that is used at other CSP power plants.
Cooling liquid salts release energy that is used to produce steam, which turns turbines and generates electricity that is transferred to a general grid hookup at the plant. This structure is similar to coal based power plants where molten salts replace the need for fossil fuel burning.
The $325 million 19.9MW equivalent plant is a joint venture, between the Spanish engineering and construction firm Sener that owns 60% and investment partners from Abu Dhabi’s Masdar energy company.
The price per MWp is almost 10 times that of a standardized PV based plant, however the PLF’s of 60%+ allow for a quicker recover period. The technology is more suited for large scale plants of 100MW+ where better sweet spots are