Numerous types of fuel cells are known and the respective technologies are selected according to the intended applications. The alkaline low temperature fuel cell shows a huge electrical efficiency factor, can operate with inexpensive catalysts and diaphragms or separators. Thus, this cell is ideally suited for use in combination with alkaline water electrolysis. Its single disadvantage, the CO(2) intolerance of the alkaline electrolyte, is not a problem in this case. These inexpensive systems can be used when a certain number of unsteadily producing solar plants shall form a combination of decentralized base load power plants. In this case, the storage of energy in batteries or electrolysis-and fuel cells, respectively, can guarantee for a stable energy feed-in.