We are living in a highly technologized environment. Thus the constant supply of energy is essential for many applications. Especially IT and communication technology is essential for processes, workflows and business transactions. Also the increasing demand for public safety results in continuously running equipment for control and information systems or security surveillance. In order to support this backbone of our daily life, critical infrastructures are quite often equipped with an uninterruptable power supply (UPS). Fuel cells can already be used for such applications.