抄録
The grid cost related to prediction errors in the power output of Variable Renewable Energies (VREs) is estimated to be 21 billion YEN in Japan. This issue needs to be addressed in order that VREs, especially for solar Photovoltaic (PVs) systems, become one of the major power resources in the Japanese electricity market. Energy management systems using demand side resources are expected to be one of the promising solutions, however, relatively little attention has been paid on the potential of residential fuel-cells (FCs) compared to the other sources including Electric Vehicles (EVs), heat-pump water heaters and batteries. This study highlights the potential of FCs for offsetting PV output imbalance caused by errors in day-ahead predictions, and the PV imbalance mitigation system was developed. In the system, the power output from FCs were controlled and adjusted remotely to offset the imbalance caused by PV through real-time monitoring. 1 MW PV systems and more than 3000 units of FCs are used to evaluate the developed systems. The results from this empirical research showed that the system could reduce the imbalance from 64% to 72% depending on the accuracy indicators used for the evaluation. In addition, we found the developed system can contribute to greenhouse gas emission reduction by both substitution of grid electricity and support of stable supply from PV as is pointed out in the previous study.
