Technical and economical comparison of micro CHP systems

Micro CHP (combined heat and power) systems, as examples of decentralized energy systems, will play a central role in the future energy supply. This study, based on technical and economic factors, compares different micro CHP systems. A market-analysis, in Germany, revealed five different micro CHP technologies from different manufacturers. Eight representative micro CHP plants were chosen from these manufacturers for further investigation. These plants included two fuel cells, two Stirling engines, two combustion engines, one micro gas turbine, and one steam engine. Energy supply from the micro CHP plants to a single-family home was simulated. A simulation tool has been developed that calculates the annual costs of a micro CHP systems under real conditions. Economic comparison of micro CHP systems is based on thermal initial costs. Results, based on economic considerations, indicate that only a few micro CHP plants are appropriate for use in a single-family home. Most of the evaluated plants have a rated power that exceeds the energy demand of a single-family home. However, it can be stated that, in comparison with conventional condensing boilers, several technologies and products show promising economic results. Further studies will focus on objects with higher thermal demand. This study focuses on power and energy consumption within the German market and many national federal laws were taken into account. The method and the developed simulation tool are universally valid and can easily be adapted to other markets