A comprehensive overview on water-based energy storage systems
They concluded that an optimized solar pit thermal energy storage including flat plate heat exchanger is able to store 3511.0 GJ of solar energy annually which is equal to the same amount of heat produced by burning 119.83 tons of standard coal and decrease the emission of 313.95 tons of CO2, 1.02 kg of SO2 and 0.89 kg of nitrogen oxides; these results