Germany’s market-leading residential energy storage system maker Sonnenbatterie is to enter the UK residential energy storage market with its lithium-ion storage system Sonnenbatterie eco.

Benjamin Schott, director of business development at Sonnenbatterie, told Solar Power Portal's sister site PV Tech Storage that its residential storage product, which has a modular design and can be customised between 2-16kWh capacity, has already been a “big success” in Germany and now in the UK the firm wants to focus primarily on PV customers who want to increase their solar self-consumption.

Former PV installer David Hunt's specialist renewable energy recruitment company Hyperion Executive Search has been appointed by Sonnenbatterie to hire a UK country manager to “spearhead their introduction to the UK energy storage sector”.

Sonnenbatterie holds the largest market share in Germany, having sold around 8,000 units out of an estimated 20,000 overall installations in the country. Consultancy firm EUPD Research, which tracks the market said 8,300 systems had been installed in Germany by the end of 2014 and estimates a further 12,500 new systems will have been deployed by the end of 2015.

Sonnenbatterrie has now signed an agreement with UK-based energy storage system provider Green Acorn to act as the first 'Sonnenbatterie Centre' in the UK, serving the south west and Scotland.

Schott said the two firms are in a trial phase this year with plans to go commercial by the beginning of 2016. Sonnenbatterie's strategy is to have an exclusive agreement with local installers to sell, install and service the systems when required.

Schott added: “It is the same model we have in Germany already and that [model] is part of our success.”

Business models for contrasting market drivers

The German firm’s entrance into the UK, where there are an estimated 750,000 PV systems installed on domestic rooftops already, comes just a few months after the UK’s Department for Energy and Climate Change (DECC) proposed dramatic cuts to Feed-in-Tariffs (FiTs) by as much as 87%.

While the announcement has caused widespread disruption in the UK PV industry, it has also been touted as a potential opportunity for the energy storage market. Without FiTs giving strong incentives to export solar power back into the grid, it makes sense to maximise self-consumption of solar and this can be achieved through retrofitting with storage, Schott told PV Tech Storage in August.

Meanwhile, for new PV installations, combining with storage now becomes a method of saving money, rather than generating attractive returns while under the original FiT model – if the FiT cuts go ahead, as widely expected.

Looking ahead, Schott said: “Our systems are designed for integration into virtual power plants, so we are speaking to utilities and grid operators to start something in that direction, so our systems can be remotely controlled.”

While the firm plans to head in this direction where multiple batteries are aggregated together to perform various functions such as grid-balancing, already doing so in a number of pilots in Germany, Schott said this service cannot be offered in the UK until the firm has enough storage systems “in the field”.

Sonnenbatterrie is based in Wildpoldsried, Germany, with offices in Los Angeles, California. In June, it also opened a research and development (R&D) facility in Atlanta, Georgia. At the time, PV Tech Storage reported that Sonnenbatterie was racing Elon Musk's Tesla to enter the US energy storage market. Conversely with the UK offering and in Sonnenbatterie's homeland, the company's initial launch into North America was in the commercial market segment, where peak demand charges can form as much as 50% of operational electricity bill costs and can be mitigated to a greater extent with storage.

Sonnenbatterie also continued its push into the US by partnering with Sungevity, the residential PV installer founded by environmental activist and cleantech entrepreneur Danny Kennedy.