Abstract
Decentralized power generation in private homes, especially by photovoltaic systems, is already common in Germany. The developments of batteries, both for electric vehicles (EV) and for stationary storage might lead to a mass market for those batteries. In this paper we evaluate the economy of stationary battery storage with photovoltaic system at home in the context of available EV and its integration level into the home. Therefore, we use an optimization model with one year detailed operation planning and maximize the net present value of the storage investment. We integrate restriction functions for the technical parameters of the storage systems and limit EV availability and usage on the basis of German mobility studies for single vehicles. The results show, that an investment in a stationary battery system in combination with a photovoltaic system is profitable in Germany under the assumptions considered. The observed high numbers of battery cycles lead to strong requirements for battery lifetime, i. e. cycle stability and long calendar life time. Therewith, Li-ion batteries are a promising technology. In combination with an EV, the net present value of the stationary battery system is smaller when the EV is integrated into the home by controlled charging or the vehicle to home (V2H) concept, which allows discharging into the home system. The size of the EV battery, the availability at daytime and the load curve of the home are the main influencing factors for the profitability of the battery system.
Highlights
Worldwide developments in the last years, both in electric vehicles (EV) with lithium-ion based battery storage and in photovoltaic (PV) make it probable, that the market prices of batteries and PV systems will further decline, which lead in turn to an accelerated market penetration
The evaluation of the economic efficiency based on the net present value of the PV system and the stationary battery system (BS) is possible with three model configurations
In this contribution we analyze the interdependencies of electricity home storage between electric vehicles (EV) and stationary battery systems (BS)
Summary
Worldwide developments in the last years, both in electric vehicles (EV) with lithium-ion based battery storage and in photovoltaic (PV) make it probable, that the market prices of batteries and PV systems will further decline, which lead in turn to an accelerated market penetration (and vice versa). In Germany the prices for small PV systems fell only in the last four years from 4.36 €/Wp to 1.75 €/Wp [1] resulting in a renewable energy payment by law (EEG, [2]) of currently 17.02 ct/kWh (2013-01, [3]). These price reductions led to an undercutting of grid parity, as German electricity prices for homes, which rose already beyond 25 ct/kWh, are higher than PV generation costs.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
