Where Solar Energy Storage Meets Smart Grid

Can stored solar power at the residential level help to make the smart grid smarter? According to Sunverge, the answer is ‘yes.’ The company’s new Solar Integration System (SIS) came to our attention via Pacific Housing’s new 2500 R Street affordable housing project slated for Sacramento, California, where it will be a key feature in the development’s projected LEED profile.

The system works, essentially, by allowing solar energy to be stored at home, and released by the utility company during times of peak demand. This is financially significant to both homeowners and utilities, since–as part of the global push toward reduced electricity demand– consumers are paying increasingly higher costs for energy used during peak hours under “time-of-use” billing structures. Peak solar generation typically occurs in the afternoon, several hours before peak energy demand. Because the Sunverge SIS captures solar energy when it’s most abundant and stores it for use when the cost of grid-tied power spikes, it can effectively shift a household’s load from higher- to lower-priced power.

Sunverge SIS

image via Sunverge

The Sunverge SIS includes a residential, grid-tied photovoltaic solar array connected to an inverter that converts DC energy into AC energy coupled with a Lithium-Ion (Li-Ion) battery that stores captured energy. A key component of the system is the SIS Data Processing Gateway (SDPG), which enables electric utilities with smart grid programs to release that energy to the household when it’s most needed.

With more households running such systems, utility companies can aggregate SIS-stored energy in addressing various challenges that arise in meeting a district’s overall energy needs, improving power quality, responsiveness, reliability, efficiency and scalability.

All of this may sound like something that should have come into being with the very first smart meter deployed. But until recently, the cost of Li-Ion batteries was too high to make such a system feasible. With the advent of mass-produced electric vehicles like the Nissan Leaf and Chevy Volt, that has changed, as economies of scale have decreased the cost of production. Likewise, the rise of solar power worldwide in the past few years has helped to drive down the cost of solar cells–two factors that converge in Sunverge’s vision for affordable, grid-tied distributed solar.  

Susan DeFreitas has covered all manner of green technology for EarthTechling since 2009. She is a graduate of Prescott College for the Liberal Arts and the Environment, and has a background in marketing green businesses. Her work on green living has been featured in Yes! Magazine, the Utne Reader and Natural Home.