Energy storage start-up Stem says it sees a “strong opportunity” for expansion of its business in Australia, Japan and the EU and is especially focused on the potential of aggregated 'virtual power plants', in the week when the company closed a US$12 million funding round led by Japanese trading company Mitsui & Co.
The participation of Mitsui & Co, one of Japan’s largest trading companies, in Stem’s Series C funding round, was announced by both parties at the beginning of the week. Mitsui stated that it was interested in numerous business cases for energy storage, including aiding the increased adoption of renewable energy, boosting grid stability and in markets where time-of-use charges exist, hedging against those.
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A Stem spokeswoman confirmed to PV Tech that it wants to use the investment to greatly expand its activities in grid-balancing through the aggregation of customer-sited storage devices. At the individual system level, Stem's software and energy management systems use so-called 'big data' and predictive analytics to model a customer's energy profile and make recommendations to maximise savings on their energy bills and reduce demand. When connected together as a network, the systems can also offer grid stabilising and other services.
According to Chris Edgette of the California Energy Storage Alliance (CESA), this could mean combinations of residential PV storage batteries and commercial storage installations. A number of trial deployments of such concepts are currently underway around the world, including a 0.5MW trial in the UK by storage maker Moixa, which has aggregated the capability of 250 connected residential solar storage batteries for a pilot by the government Department for Energy and Climate Change (DECC).
“By aggregating customer-sited storage systems, Stem’s network can serve as capacity to replace peaker plants, control voltage, enable a better demand response solution and provide customers a way to earn revenue from participating in grid services,” the spokeswoman said.
The tie-up will help Mitsui to reach further into the US market, while allowing Stem better exposure in Japan, Mitsui said. The investment was also conducted as part of a programme by Mitsui to identify innovative technologies with business potential.
Mitsui has taken an increasing interest in participating in the energy industry as an Independent Power Producer (IPP) and is keen to develop its “new power business” further. The energy market in Mitsui’s home territory is to be deregulated over the next couple of years, which, if successful would mean that businesses – and individuals – could become independent power producers (IPP). For example, at February’s PV Expo in Tokyo, Panasonic was already showcasing a new residential energy management system for rooftop solar combined with storage that allows the homeowner to buy electricity at the cheapest available prices and sell at the most attractive. Other Japanese companies including telecoms provider turned solar developer Softbank have already registered their interest in the retail electricity business.
For the full version of this story, including more on virtual power plants and international market conditions for electricity storage, visit PV Tech Storage.
