Solar microinverter specialist Enphase has announced its first move into energy storage, launching an energy management system (EMS) which includes an AC battery, at the Solar Power International show in Las Vegas this week.
The product is aimed at integrating solar photovoltaics (PV) with storage, cloud-connected communications and load management. Simply titled Enphase Energy Management System, it is comprised of four main components, a bi-directional smart-grid ready microinverter, the aforementioned AC battery, a plug-and-play communications unit and energy management software.
Enphase’s AC battery is described as a “modular, plug-and-play device”, and is designed for both commercial and residential applications. Unsurprisingly, it allows for solar energy generated by the system to be stored for night-time or future use. Several installation companies have been engaged for pilot projects including one of the US’ biggest solar installers, Vivint Solar, with pilots in regions that include the US, Europe and Australia.
The battery is provided by ELIIY Power, a Japanese company backed by Daiwa House, the homebuilder and renovator considered to be one of Japan’s largest. The battery uses lithium iron phosphate battery chemistry, one of the many sub-chemistries of the lithium-ion battery family. Enphase co-founder and vice president of products and strategic initiatives Raghu Belur said ELIIY Power had been selected after an “extensive evaluation” of several different companies and battery chemistries. Belur said particular consideration had been paid to battery performance and safety. Used in conjunction with the microinverter, the AC battery can provide 1.2kWh of energy storage and power output at 275W/550W, which is scalable.
An Enphase microinverter-powered solar array at Hartley's Crocodile Adventures, Australia. Image: Enphase.
The microinverter, Enphase S-Series, is designed to allow the maximum penetration of PV-generated energy onto the grid, according to Enphase. Supporting advanced grid functionalities such as reactive power control, the microinverter meets California regulations for interconnection, operation and metering of distributed generation, under Electric Rule 21.
The company’s Envoy S communications hub provides features from energy monitoring to revenue grade metering of solar power production, of home energy consumption and also management of the battery. The energy management software, Enphase Enlighten, allows for remote monitoring of system performance via computers and portable devices including tablets and smartphones, as well as allowing users to optimise the use of the three available energy sources: the solar array, the battery and power from the grid.
Enphase’s Energy Management System and AC battery is being prepared to go onto the market in the second half of 2015. Enphase claims the system as a whole will provide better return on investment (ROI) for system owners, provide additional revenue streams for installers and “broader insight into and control for utilities”.
Talking about the launch of the AC Battery, for which a separate announcement was made to that announcing the Enphase Energy Management System, Raghu Belur spoke of an expected “multi-billion dollar market” for energy storage. He also said integrated storage would be “essential in helping solar gain broader acceptance and higher penetration”.
“…(the AC battery) provides benefits for the system owner, while also helping with grid stability. We are bringing the same technological innovation to storage that we brought to solar, by pairing our innovative distributed architecture with the best-in-class battery chemistry in the industry."
The Enphase AC battery which is integrated into the company's Energy Management System. Image: Enphase.