This study investigates the performance of hybrid renewable microgeneration systems in load sharing application between a detached residential house and a small office building. Two renewable energy systems are investigated: a ground source heat pump (GSHP) system and a hybrid GSHP/fuel cell (FC) system. The renewable systems performance is compared to a conventional system that utilizes boiler and chiller to meet the thermal loads of the two buildings. 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 showed that, by implementing a single GSHP system able to meet both heating and cooling loads of the buildings, an overall energy saving of 39% can be achieved mainly due to the introduction of a significant renewable component. The integrated hybrid GSHP-FC system results an overall energy saving of 24%. However, the hybrid GSHP-FC system generates additional electricity and based on the energy pricing structure can lead to more significant cost savings. Additionally, the GSHP-FC 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 and for inclusion in the "smart" grid applications. (C) 2012 Elsevier Ltd. All rights reserved.