Abstract: The ever-increasing consumption of finite resources of fossil fuels and global environmental concerns have accelerated the efforts to develop efficient and affordable electrochemical energy storage and electricity generation devices. Electrochemical reduction of oxides to fuels in molten salts using renewable energy sources such as solar and wind power is an effective way for converting electrical energy to chemical energy in fuel itself; this energy can be converted back to electricity when the fuel is electrochemically re-oxidized in fuel cells. These processes can be related with the molten salts enabled electrochemical cycling between oxides and solid fuels. Because solid fuels are of high density and stable in air, they are suitable for long term storage and long distance transportation. Therefore, we anticipate that the realization of "seasonal energy storage" (SES) and "regional energy storage" (RES). The purpose of SES is to store energy harvested in the sunny summer and reuse it in cold winter, whilst the RES aims to collect energy from remote desserts (sunlight to electricity) or mountains (wind to electricity) to urban areas. Preparation and application of the regenerative fuels via electrochemical process in molten salts are discussed.

Key words: molten salts, electrochemistry, regenerative fuels, fuel cells, carbon dioxide