Profitability analysis of grid-connected photovoltaic facilities for household electricity self-sufficiency

Spain exhibits a high level of energy dependence and has significant solar energy resources. These two facts have given rise to the prominence that renewable energy, particularly solar photovoltaic technology, has enjoyed in recent years, supported by a favorable regulatory framework. Currently, the Spanish Government is providing new ways in energy policy to enhance and accelerate the development of low-power photovoltaic generation facilities for self-consumption by introducing energy policies for feed-in payments of surplus electricity. Such facilities are an example of distributed electrical generation with important benefits for the environment and the rest of the electrical system because, when properly managed, they can help improve the system’s stability and reduce overall losses. By analyzing household demand and solar photovoltaic energy resources, the profitability of such facilities is considered in this article, taking into account the technical and economic impact of storage systems and proposing models for feed-in payments of surplus electricity, in an attempt to assess whether this method of electricity generation versus the method of conventionally supplied power from a grid at a regulated tariff can rival each other economically, in terms of parity. ► The use of grid-connected photovoltaic facilities for household electricity self-sufficiency is presented. ► The need for legal frameworks that include retributive mechanisms for the surplus energy is pointed out. ► Two models are proposed for the remuneration of surplus energy generated. ► Models show economic profitability without feed-in-tariff or compensations. ► Facilities described offer ancillary services for grid stability and smart-grid integration.