Modeling self-consumption from PV and home battery systems in Spain: economic impact of the regulatory framework

Abstract

The latest developments of battery technologies for solar applications have created high expectations in the field. Certain press articles claim that this new advances could revolutionize the solar energy sector and lead to autonomous residential PV systems or micro grids. Nevertheless, this assumptions lack of a proper scientific evaluation and it is still unclear when and under which circumstances battery storage can be viable without government subsidies or policy support. This thesis explores the economical profitability of a grid connected PV system with and without battery in a standard dwelling in Spain for two different crucial moments of the Spanish photovoltaic regulation: 2008 when the solar energy boom occurred and 2016 when the solar energy sector is facing one of its weakest periods. Three different scenarios have been evaluated to find out under which economic conditions, domestic batteries are profitable, considering the different changes in the photovoltaic legislation. Results indicate that latest change in the legislation, which eliminate FITs and add new fees to self-consumed electricity hinder the development of self-consumption. Concluding that without policy support battery storage is not yet economically feasible in Spain.