Power grid startup Varentec has announced its completion of a series C funding round that drew further funding from existing investors Bill Gates, 3M Ventures, and Khosla Ventures.

The Silicon Valley start-up did not disclose how much was raised in the latest round, but did start the round with a $13 million investment from the three aforementioned investors in November.

Varentec said that the funding would go towards international expansion and the continued development of the company’s Grid Edge Management System (GEMS) software platform and control devices.

The company began working with the Hawaiian Electric Co. in April to install and control grid controls on the island of Oahu. The island has seen a surge in rooftop solar power installations, which can make grid management more difficult.

Varentec is anticipating that utilities will begin large-scale investments in volt/VAR optimization (VVO) and Conservation Voltage Reduction (CVR) programs as part of the multi-year strategic grid modernisation plans.

Guillaume Dufose, Chairman and CEO of Varentec said; “"It will be key to helping utilities achieve ambitious grid efficiency, peak demand reduction and energy savings targets. This Series C funding, with the backing of 3M Ventures, Bill Gates and Khosla Ventures, further demonstrates the engagement of our shareholders to bring a new concept of grid efficiency to market."

Varentec products are billed as having low-voltage and real-time control capabilities which provide significant performance differentiation compared to traditional slower, centralized software-based solutions.