How are batteries helping integrate solar photovoltaics into the electricity system?

Blog Post created by joaofonseca on 13-Jun-2017

A new study proves decentralized storage improves the efficiency and resiliency of the digital grid, highlighting the importance of including batteries in the development of a smarter electricity system.

Lower costs coupled with proven system performance are allowing photovoltaic (PV) plus batteries to compete with retail electricity prices and grid parity is being achieved in some countries such as Germany. Introducing full integration of PV’s into the grid require a reformulation of the way electricity distribution is perceived and presents new challenges for distribution system operators (DSOs) who will have to adapt to innovative business models to generate value as well as review new roles and responsibilities of different network actors.

A study developed by EY and one of Europe’s leading DSOs has found that it would reap economic benefits across the entire electricity system if batteries were installed on the consumer-side in a near future, particularly as more electricity customers are increasing their PV deployment and becoming prosumers. Given the current price evolution it was observed that for the end-user, batteries would already be beneficial when prices are reduced to 140€/kWh which is estimated to be achieved by 2020.

The study analysed both the economic and technological feasibility of integrating decentralized battery storage into the grid and found no technological barriers from a grid losses perspective or from current or voltage violations. In fact, it was discovered that use of consumer-side batteries would increase the robustness and resilience of smart distribution grids. The overall consumption of energy would drop by a quarter when introducing both PV’s and batteries at the client’s level and by 75% during summer.

The key takeaway from this study is that batteries at the client-side lead to a reduction of an internal energy fluxes, resulting in increased hosting capacity given that grid losses increased exponentially up to 2,5% with the introduction of PV deployment and decreased linearly with the introduction of batteries down to 1,5%. However storage alone is not the silver bullet for a more stable grid as it should be coupled with smart grid components such as systems which combine artificial intelligence with energy management, to maximize its benefits.

The key question is – are utilities prepared for what may be a boom in decentralized storage?

I’ll be talking more about this study and its implications for DSOs at CIRED 2017, the major conference of the global electricity industry, in Glasgow, tomorrow afternoon. Please come and say hello if you are attending. 

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