Metal hydrides can be utilized advantageously as working materials in
a number of devices which can contribute significantly to an environme
ntally clean energy technology. Among others, there are heat transform
ers, heat pumps and refrigerators which allow one to use low-quality t
hermal energy (e.g. waste heat) to generate high-quality thermal energ
y or cold, and there are thermal energy storage systems which can be a
pplied in solar energy stations or in industry. This paper describes t
wo developments which shall lead to prototype systems of a heat transf
ormer for industrial use and a thermal energy store for small-scale so
lar energy stations.