Self-Sufficiency in an MCHP System Based on Local Demand and Supply Analysis

Micro-combined heat and power (MCHP) systems generate heat and electricity concurrently, making them an ideal addition for home and small/medium business owners to generate their own electricity and replace conventional natural gas-burning boilers. Combining MCHP units with thermal and electric storage systems can aid in decoupling supply and demand of energy. In such a combined setup, MCHP units can run for prolonged periods when they not only cover existing demand but charge storage systems for deferred consumption of energy. In the present work, we analyzed such an MCHP system, with a particular focus on integrating electrical storage systems and the resulting degree of electrical self-sufficiency achievable under realistic working conditions. We implemented a system control logic to optimize MCHP unit run time geared towards taking energy storage system charging levels into account. We demonstrate that an MCHP unit and electrical storage system can complement each other benefitting overall system performance. Separating days according to their respective degree of electrical self-sufficiency enabled us to identify supply composition characteristics that result in higher electrical load coverage by MCHP-generated electricity.