A new kind of battery

  JUN 23, 2016

Harumi Fuji McClure and her husband live in a nice, two-story house in Morgan Hill south of San Jose. It gets pretty hot there in the summers, so they have a large swimming pool and air-conditioning in the whole house. But her electricity bill isn’t high: it’s negative five dollars a month.

Yes, Fuji McClure actually gets money back. This is because of the solar panels and the battery storage system she uses to power the house.

Fuji McClure walks into the garage to show me her battery system. It’s a gray metal box, about the size of a hotel minibar, tucked away in a corner. Fuji McClure says most of the time, she and her husband don’t even realize the battery is there.

A new kind of battery

Fuji McClure works for the Japanese company Tabuchi Electric, which recently started selling batteries on the US market. They work by charging up on solar, then storing that energy so it can be used as electricity later on. Fuji McClure became interested in the batteries after the earthquake in Japan in 2011. Over half a million people were without power; her coworker, however, had solar panels and a battery at his house. She says while other people couldn’t even take a hot shower, his life didn’t change much.

Fuji McClure claims that the batteries have become more popular in Japan since then, and people in the U.S. are getting interested too. Americans buy their batteries from electric car companies like Tesla, which has already sold thousands this year, or purchase them as add-ons with solar panels.

Big batteries and clean air

Like in Japan, some people in the U.S. use their batteries for emergency back-ups in situations like earthquakes, while others want to lower their dependence on fossil fuels. Then there are those who are thinking even bigger, like energy storage expert and battery advocate Janice Lin, who says batteries could dramatically decrease pollution. Lin describes the link between battery storage and pollution by comparing our current gas generators to cars. When we’re city driving, we don’t get as good gas mileage and we create more pollution than during freeway driving. Right now, most people’s energy consumption is like Bay Area traffic, irregular and with lots of stops and starts. We are out during the day and when we come home, we turn all of our appliances on at once. In the future, Lin thinks that extra, sudden burst of energy could come from a battery that has been charging up on solar power all day.

“When we put energy storage or a little bit of inventory in our electric power system it makes our system run more smoothly, more efficiently and with less pollution,” says Lin. “That makes our air more livable and more breathable, and it makes our electric bills a whole lot cheaper.”

Batteries for everyone?

That’s the ideal vision. Not all clean energy advocates share it. Al Weinrub is the coordinator of the Local Clean Energy Alliance in Oakland, and he doesn’t think batteries are a realistic solution. Instead, he wants to see a large-scale economic development plan which addresses real human needs, and he considers getting off fossil fuels and living in sustainable communities as two of the most basic. That is why he is interested in creating net-zero communities — neighborhoods that create as much energy as they use — not just net-zero homes.

Some kind of energy storage is part of that vision, and Weinrub is willing to try these new batteries. But he urges people to also consider their environmental impact, and think about who is producing them. He would like to know if they can be produced in locally, and if there is another technology that might be more appropriate. Battery systems like Fuji McClure’s cost about $13,000, which has Weinrub asking,“how do you finance this for low-income communities?”

Energy storage advocate Janice Lin thinks that the price will come down as batteries become more popular. She is also hoping lawmakers will catch on to the benefits of batteries and make them easier to access. There is already a state-run incentive program to make it more affordable, the Self Generation Incentive Program.

“As with any new application introducing a new product it’s a new thing, it’s a new behavior and so that’s why these incentives are absolutely necessary,” says Lin.

A teaching tool

In Morgan Hill, Harumi Fuji McClure walks back into the house to show me a little monitor on the wall in the hallway. It looks like an alarm system but this screen shows a house, a battery, a power station, and a brightly shining sun with arrows connecting the different symbols. She asks me to keep an eye on the screen as she turns on the drier, one of her home appliances that uses the most electricity. As the drier begins its hum, the arrows on the monitor start pointing to the house from the battery and the sun to indicate where the power is coming from.

“I think this is a great tool not only for us to save money but for kids to learn where energy comes from and how to save it,” says Fuji McClure.

It’s not just about saving energy; it’s also about generating it. Fuji McClure now has so much extra energy stored in her battery during the day that she can actually sell some back to PG&E. She is counting on getting about $3,000 back every year through those sales and the energy incentive programs she is enrolled in. She is happy about that, but it will still take her five years to break even on what she paid for the battery. She’s expecting the battery to last for five more years after that, then, it’s off to recycling­ and she will have to decide if it’s worth it to invest again.