It’s been less than a year since Andrea Divis moved into a two-story Oceanside home in San Diego County.
“It’s cozy and comfortable, and really the backyard is like my oasis,” Divis said.
He deals with a chronic illness that prevents him from going without air conditioning or refrigeration for his medication.
“When I was in Oregon, I was paying, I don’t know, $150 a month for my utilities,” Divis said. “Now I come here and the lowest month it was $200 and I made $450, $480.”
Divis saw solar as a solution. He added energy-generating panels to his roof and just inside his garage is a new Sonnen battery.
The battery stores excess energy generated on its roof during the day. He then uses the environmentally friendly energy to power his home between 4:00 PM and 9:00 PM. It is San Diego Gas & Electric that is increasing the cost of electricity to promote conservation.
“We have sunshine in Southern California,” Divis said. “Let’s use this to our advantage. We shouldn’t use crude oil and all that kind of stuff.”
Its home Sonnen Battery is developed by a German company owned by Shell, a global energy company with a long fossil fuel legacy.
Sonnen has developed software that allows the company to control thousands of household batteries that, when used collectively, become a virtual power plant.
They already have a system in Germany and are looking into doing the same in several locations in the US.
A simple modem connection becomes a bridge to build a virtual energy storage that could help California avoid future power shortages.

“We saw Flex Alerts saying, ‘Hey, we have more demand than production; We need people to downsize us,” said Mike Teresso of Baker Electric Home Energy.
Sonnen is partnering with Baker to install its batteries and solar panel systems in San Diego County.
“Well, if we have these batteries with stored energy, that energy can be injected into the grid and help stabilize the grid,” Teresso said.
The company has only sold a few dozen Sonnen batteries in San Diego County, but the partnership is new.
Batteries do not need to be located locally to be part of a bundle.
The program can connect batteries scattered across the state because Sonnen deals directly with the California Independent System Operator (CAISO), which manages the electric grid. No utilities needed.
Sonnen discusses the cost of electricity storage and sharing the revenue with residential owners.
“Hey, that battery could be more,” Teresso said. “It’s not just for backup. It’s not just stored energy for you to use in one event. And it’s not just for you to use between four and nine when rates are high. This battery now has real value to the market and you can be part of a California grid that is becoming more stable and more robust.
Sonnen battery owners receive an upfront fee of $750 to sign up to be part of the virtual power plant. There are small fees for keeping the battery on the grid, as the availability of standby power is an important part of the electricity market.
As the grid must meet the demand for energy, if the energy is actually obtained from the battery, the residents receive a reward from CAISO for the electricity they provide.
Having a certain amount of standby electricity available is important to grid managers as they coordinate supply and demand.
“This is the next step beyond putting solar on the roof,” said Blake Richeta, chairman and CEO of Sonnen. “This should save more money on their electricity bill. It should actually pay them for their services. Help us move away from fossil fuel-based power plants.”
Sonnen needs between 5,000 and 10,000 connected batteries for a virtual power plant to have a significant impact on grid operations, but the potential is much greater than that.
“Having a smarter grid that’s more flexible, that can balance generation and load, and that can handle grid challenges, I think is important for the future,” Richeta said. “One day millions of batteries should be available. And that will allow us, among other solutions, to decommission all coal-fired power plants once and for all.”
But Sonnen faces obstacles as the company tries to scale the idea.
Sonnen needs more people to buy the company’s household batteries because the system won’t work with batteries made by other manufacturers, such as Tesla or LG.
Courtesy of Baker Home Energy
State regulators have also recently reduced the cost of rooftop electricity sold back to the grid, making solar/battery systems less financially attractive.
Industry watchers aren’t sure how fast or how many solar/battery systems are installed.
While there are federal incentives to install the technology, California does not have them.
The Public Advocate for the California Public Utilities Commission recently suggested that the state legislature might approve the incentives, but that’s not certain.