Performance analysis of a hybrid renewable microgeneration system in load sharing applications

Governments around the world are taking measures to minimize the humans' impact on the climate and environment by reducing emissions and energy use in all sectors. Microgeneration utilizing renewable energy is a suitable approach to reduce energy consumption and carbon emission by offering high efficiency performance, offsetting the need for centrally-generated grid electricity and avoiding transmission/distribution losses associated with it. This study investigates the performance of a hybrid renewable microgeneration system in load sharing application between a detached house and a small office building. Two renewable energy systems are investigated: a ground source heat pump (GSHP) system and a hybrid GSHP/Photovoltaic Thermal (PVT) microgeneration system. The performance of the renewable systems is compared to a conventional system that utilizes boiler and chiller to meet the thermal loads of the two buildings. Computer models are developed for the three selected systems and then simulated in TRNSYS-17 environment over one full year under Ottawa, Canada weather conditions. The simulation results show that, by implementing a single GSHP system able to meet both heating and cooling loads of the buildings, an overall energy saving close to 46% can be achieved mainly due to the introduction of a significant renewable component. The integrated hybrid GSHP PVT system, however, results a much higher overall energy saving of 58% due to the contribution of both geothermal and solar energy. Additionally, the GSHP PVT microgeneration system's capability to generate both heat and power at the point of use is considered more attractive for new and remote community applications where lack of central generation stations and costly connection to the grid is neither an affordable nor a preferable option. Furthermore, reducing the buildings' dependence on the electricity grid also fits well with the "smart grid" concept and with utilities various load shaving and load levelling strategies. (C) 2013 Published by Elsevier Ltd.