Modeling and Performance Analysis of an Integrated System: Variable Speed Operated Internal Combustion Engine Combined Heat and Power Unit–Photovoltaic Array

The paper presents the model of a combined heat and power (CHP) unit, based on a variable speed internal combustion engine (ICE) interfaced with a photovoltaic (PV) system. This model is validated by means of experimental data obtained on an 85 kWe CHP unit fueled with natural gas and a PV system with a rated power of 17.9 kW. Starting from daily load profiles, the model is applied to investigate the primary energy saving (PES) of the integrated CHPþPV system in several operating conditions and for different sizes of PV array. The results demonstrate the dependence of the CHP performance on the operating mode and a limited convenience of the variable speed strategy. The integrated system operation leads to performance improvements, which depend on the size of the PV component.