Hybrid Gas Motor and Heat Pump Energy System for Commercial Buildings

The global energy sector is currently undergoing a major transformation toward sustainable, low-carbon, and energy-efficient technologies. Commercial buildings are among the largest consumers of electrical and thermal energy due to heating, ventilation, air-conditioning (HVAC), lighting, office equipment, and domestic hot water demand. Conventional building energy systems typically rely on separate electricity generation from the power grid and fossil-fuel-based heating systems such as gas boilers. These systems suffer from low overall efficiency, high operational costs, poor waste heat utilization, and significant greenhouse gas emissions. This project presents a hybrid Gas Motor (EMS) Combined Heat and Power (CHP) and electrically driven Heat Pump system modelled in MATLAB/Simulink. The system is coordinated by a rule-based Energy Management System. The EMS receives electricity price, gas price, outdoor temperature, building heat demand, and heat-pump temperature suitability as inputs. It produces an operating mode, gas-motor command, and heat-pump electrical command. The gas motor is represented by 30% electrical efficiency, 55% thermal efficiency, and 15% losses. A heat-exchanger efficiency of 95% is used to recover useful heat. The heat pump is represented using an outdoor-temperature-dependent COP characteristic, with representative COP values from 2.2 at −10 °C to 4.5 at 20 °C. The total useful heat is evaluated from recovered CHP heat and heat-pump output and is compared with building demand. For the reported German office-building case, annual gas consumption decreases from 171,952 kWh to 84,000 kWh. Net annual operating cost decreases from €21,282 to €10,985, giving a saving of €10,297 per year. Net annual CO₂ emissions decrease from 44,326 kg to 13,834 kg, equivalent to a 68.8% reduction. The results demonstrate the potential of EMS-controlled CHP and Heat Pump integration for improving energy utilization, reducing operating cost, and lowering emissions.