Elektrische Wirkungsgrade von biogasbetriebenen BHKW

Over a period of up to six years, nine combined heat-and-power units (CHPU) running on biogas were measured for electrical efficiency. The electrical capacity of these units ranged from 30 to 526 kW. From the first to the last measurement, the electrical efficiency of the systems decreased significantly. In the case of the oldest CHPUs the decrease reached almost 5 percentage points. This effect of ageing could be counteracted by systematic and consistent maintenance.