Photovoltaics as an Energy Services Technology: A Case Study of PV Sited at the Union of Concerned Scientists Headquarters

Abstract

This paper presents a technical and economic analysis of the Union of Concerned Scientists' (UCS) 2.1kW photovoltaic (PV) array located on the roof of their Cambridge headquarters. We analyze the technology from a variety of different perspectives. The system as it currently exists is primarily an energy supply technology. Alternatively, the system could be reconfigured with the addition of a modest amount of storage to serve energy management functions, primarily offering firm, peak-shaving benefits on a daily and yearly basis. This value would be enhanced with better energy management by UCS of their heat pump cycles. We also analyze the economics of the UCS PV array serving an additional emergency power function. The results of our analysis indicate that the economic value of the UCS PV array would be optimized in a configuration that serves all three functions: energy supply, energy management, and emergency power. In fact, we estimate that the payback period for the system configured in this fashion would be approximately five years.