Alkali metal thermoelectric converter (AMTEC)

The alkali metal thermoelectric converter(AMTEC) utilizing the sodium ion conducting β″-aluminum is a device to convert directly heat energy to electric energy. It is characterized by high conversion efficiencies (20 ≈30%), high power densities (≈ 1 W/cm²), no moving parts and low maintenance requirements. Because of these merits, AMTEC is one of the most promising candidate for dispersed small scale power station, remote power station and aerospace power systems. The AMTEC cycle had been proposed by Ford Motor Company. Up to date, the specific power densities of 1.1 W/cm², the conversion efficiencies of 19%, and duration time of over 1000 hours have been demonstrated in Ford Motor Company. In ETL, the specific power densities of 0.79 W/cm², the conversion efficiencies of 30% and the power of 12.3 W in two series connected cells have been demonstrated. And also, it has been made clear that the AMTEC power system has the capability of over 50% of conversion efficiency. The basic research phase on AMTEC would be completed now and the system research phase would going on. The further AMTEC research has been proposed aiming to develop the combined power station with such as high temperature gas reactor and/ or solid oxide fuel cell.