Integration of PV+storage - technical and economic evaluation at distribution grids

Incorporation of energy storage units to solar PV plants in small-scale applications has been attracting major attention from the manufacturers worldwide in the past few years. This consolidated into both technology development and commercialization. Most of the solar PV inverter manufacturers nowadays have adopted battery storage as part of their product portfolio offered together with their solar inverters. Some also provide standalone battery storage units to the consumers that can directly cooperate with the existing solar PV plants and/or loads. Despite short-term regulatory risk, the application seems still viable in the long term, where the key business case lies in the reduced cost of electricity bills and the ever-decreasing capital costs of solar PV and storage. In due course, distribution grid operators have become concerned about the possible reduced revenue from the existing tariff model due to the increasing level of self-sufficiency of the consumers. The paper summarizes the background, ideas and the initial results from the work in a Danish project whose activities cover both the technology development and operational analysis of PV and storage systems.