The second tranche in the round was led by RWE Supply & Trading, the energy trading arm of Germany-based RWE Group, one of Europe's largest electricity and gas companies. RWE Supply & Trading will also take a seat on Stem's board of directors to support the company's evaluation of new markets.

Backing from RWE is the latest in the company's history of leveraging its engineering, operations and market expertise to benefit from the growth of innovative companies that contribute to a smarter, cleaner and more efficient energy future.

'With our investment, we are pleased to support the continued success of Stem in the rapidly growing worldwide market for intelligent energy storage,' said Eric Shaw, Head of RWE Supply & Trading Principal Investments.

Stem's customer-sited energy storage system enables businesses to simultaneously reduce electricity bills and take an active role in energy markets, all without impacting daily operations. In aggregate, Stem's customer portfolio delivers rapid, flexible capacity to grid operators, easing the integration of renewables and enhancing grid stability.

'RWE brings more than a decade of successfully integrating high penetrations of renewables, across Western Europe and provides valuable case studies on the evolving grid - and the opportunity for Stem to help reshape energy delivery and consumption,' said John Carrington, CEO of Stem, Inc. 'Stem is fortunate to count the organization as a partner as we strategically expand our presence globally.'

Stem's Series C round opened earlier this year with a $12M tranche led by Japan-based Mitsui & Co. Existing investors also contributed to the raise which was oversubscribed by fifty percent.

About Stem

Stem, a leading provider of intelligent energy storage, combines big data, predictive analytics and energy storage to simultaneously reduce electricity costs for businesses and in aggregate, deliver services to the grid. Stem's software learns a customer's unique energy profile to maximize savings and displays real-time and predicted energy use alongside actionable recommendations. When aggregated, Stem's customer-sited storage network offers flexible, cost-competitive capacity to the grid. Headquartered in Millbrae, California, Stem is funded by a consortium of leading investors including Angeleno Group, Iberdrola (Inversiones Financieras Perseo), GE Ventures, Constellation New Energy, Total Energy Ventures, Mitsui & Co., Ltd. and RWE Supply & Trading. For more information visit http://www.stem.com

About RWE Supply & Trading

RWE Supply & Trading is a leading European energy trading house and is the interface between the RWE Group's operating companies and global wholesale markets for energy and energy-related raw materials in both their physical and/or derivative forms.

Leveraging its extensive energy commodity expertise, RWE Supply & Trading has introduced the department 'Principal Investments'. Further information is available at www.rwe.com.