// Decentralised storage of solar power

A large proportion of the electricity produced by PV systems in Germany is fed into the low voltage grid. In regions with a high density of systems, the maximum output achieved at midday creates excess voltage in the distribution network. However, a large proportion of domestic electricity consumption occurs during the evening between 6 and 10 pm. It therefore makes sense to temporarily store the solar power decentrally.

By using batteries or chronologically shifting large loads, such as by operating heat pumps for space or domestic hot water heating at the same time as the generation peaks, ZSW is investigating how to increase self-consumption of locally generated solar power and thus relieve the grid at the same time.  Simulations describe the potential provided by PV storage systems and shed light on the economic feasibility of PV systems beyond feed-in tariffs relative to the cost forecasts for components and electricity prices.

As part of the German-French “Sol-ion” research project, ZSW is involved in the practical operation and evaluation of PV storage systems as well as in the lifecycle analysis of the battery technology involved.

Contact

Dr. Jann Binder
+49 (0)711 78 70-209
Example for strong capping to 25% of peak power by delayed battery
charging; in the afternoon, there remain feed-in peaks of only 6% of annual
PV production. Thus, peak load on the grid may be reduced by factor 4, by
reducing utilized power generation by only 6%.