Energy efficient operating strategies for building combined heat and power systems

A method was developed and demonstrated for evaluating and visualizing the optimal operating strategies for building combined heat and power systems. The method uses models of the component loaddependent operating characteristics matched to specific electrical and thermal load combinations for the building in a framework that substantially reduces the size of the search space and associated computational burden. The overall system primary energy input is determined for the range of possible operating conditions and is represented in the form of a performance map, allowing optimal component operating conditions and allocation of thermal energy to be determined by the operator or supervisory control system. The method was demonstrated for eight scenarios that were selected to cover a range of load combinations, and the optimal operating conditions were determined along with several metrics of energy use for the combined heat and power system compared to a conventional system and the overall system energy utilization factor.