Storage on Hydrides for Electrical Load-Equilibration

Summary

The storage of electric peak energy by means of hydrogen has been investigated for a stationary hydride storage₃system with a capacity of 100 – 1 000 MWh (32 000 – 320 000 m³ of Hp) under technical and economic aspects. Ti,Cr,Mn-based low-temperature hydrides developed at Daimler-Benz which store 2 % of hydrogen were chosen for the construction of the sta-tionary hydrogen storage and their thermodynamic and kinetic properties as well as their thermal conductivity as a basic factor for the technological computation were examined. The low thermal conductivity of the material is considerably improved by the admixture of metal powder — a method developed by Daimler-Benz. An operation cycle comprising 8 hours each of absorption, storage and desorption was assumed. In this case heat flow is the rate limiting factor. The Hp-storage pressure is 10 or 55 bars. Two variants (steel or concrete outer jacket) are designed and described. Depending on its size the hydride storage system consists of 2 or 20 storage units with a Hp-capacity of 16 000 m³ each. Several alternatives for the selection of a suitable location for the hydride storage system are mentioned and discussed and the investment and operating costs for 4 hydride storage systems are quoted. A comparison with the costs of other forms of hydrogen storage show that the hydrogen storage with hydrides is more economical than the storage of liquid hydrogen and pressurized gas.