GE’s venture capital unit is said to have invested a “double-digit million sum” although neither company disclosed terms of the deal they announced on Monday.

In 2015, Sonnen was the largest provider of residential energy storage systems in Germany and is rapidly expanding in Australia, the US and UK, where demand for behind-the-meter energy storage systems is quickly growing.

GE’s commitment is likely to help accelerate Sonnen’s commercial expansion, as it brings with it the power of the US industrial giant’s established brand and needed up-front financing, according to Marianne Boust, principal analyst at IHS Technology.

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