Molten salt vs silicon.

This should be the target market, if proven,  anyone using Molten-salt (in commercial use already) should use Silicon  instead.

In theory it should supercede molten salt technology overnite, if the costs and space and efficiency requirements are much less.

Therefore this is a almost proven technology.

Molten-salt technology[edit]Sensible heat of molten salt is also used for storing solar energy at a high temperature. Molten salts can be employed as a thermal energy storage method to retain thermal energy. Presently, this is a commercially used technology to store the heat collected by concentrated solar power (e.g., from a solar tower or solar trough). The heat can later be converted into superheated steam to power conventional steam turbines and generate electricity in bad weather or at night. It was demonstrated in the Solar Two project from 1995-1999. Estimates in 2006 predicted an annual efficiency of 99%, a reference to the energy retained by storing heat before turning it into electricity, versus converting heat directly into electricity.[12][13][14] Various eutectic mixtures of different salts are used (e.g., sodium nitrate, potassium nitrate and calcium nitrate). Experience with such systems exists in non-solar applications in the chemical and metals industries as a heat-transport fluid.The salt melts at 131 °C (268 °F). It is kept liquid at 288 °C (550 °F) in an insulated "cold" storage tank. The liquid salt is pumped through panels in a solar collector where the focused sun heats it to 566 °C (1,051 °F). It is then sent to a hot storage tank. With proper insulation of the tank the thermal energy can be usefully stored for up to a week.[15] When electricity is needed, the hot molten-salt is pumped to a conventional steam-generator to produce superheated steam for driving a conventional turbine/generator set as used in any coal or oil or nuclear power plant. A 100-megawatt turbine would need a tank of about 9.1 metres (30 ft) tall and 24 metres (79 ft) in diameter to drive it for four hours by this design.Single tank with divider plate to hold both cold and hot molten salt, is under development.[16] It is more economical by achieving 100% more heat storage per unit volume over the dual tanks system as the molten-salt storage tank is costly due to its complicated construction. Phase Change Material (PCMs) are also used in molten-salt energy storage.[17]Several parabolic trough power plants in Spain[18] and solar power tower developer SolarReserve use this thermal energy storage concept. The Solana Generating Station in the U.S. can store 6 hours worth of generating capacity in molten salt. During the summer of 2013 the Gemasolar Thermosolar solar power-tower/molten-salt plant in Spain achieved a first by continuously producing electricity 24 hours per day for 36 days.[19]

Hot silicon technology[edit]Solid or molten silicon offers much higher storage temperatures than salts with consequent greater capacity and efficiency. It is being researched as a possible more energy efficient storage technology. Silicon is able to store more than 1MWh of energy per cubic metre at 1400 °C.