Electricity storage compared to net metering in residential PV applications

The installation of PV systems in residential buildings has seen a dramatic increase in the last decade thanks to national policies like Feed in Tariff and Net Metering. Several users are now needing to increase their share of self-consumption to optimize the profits from their systems. Energy storage systems are entering the market in last years, claiming to provide an interesting upgrade for existing PV systems. In a broader perspective, energy storage systems will have a significant impact on the entire energy production and conversion processes. The aim of this paper is to present an analysis of the energetic and economic performance of an electricity storage system, compared with the net metering scheme, which is an effective economic support for residential PV systems in different countries. This research work is based on the Italian market as a case study, to perform a detailed analysis on the net metering scheme. Multiple parameters are considered into the calculation, including the location, the PV size, the storage size and a range of installation costs. The results highlight the main issues related to this technology, both from an energetic and economic point of view. While the economic sustainability is currently far from being reached, also the electricity losses generated in the storage system appear to be a significant disadvantage.