Brooklyn and Kauai don't have a lot in common, but residents in both places are betting big time on something called "grid storage," which allows communities to bank energy until they need it.
SolarCity shareholders met today in the Bay Area and approved a merger with Elon Musk's Tesla. "Vote tally shows ~85% of unaffiliated shareholders in favor of the Tesla/SolarCity merger! Thanks for believing," Musk tweeted Thursday afternoon.
The merger will likely supercharge a growing trend of big battery facilities that can store enough electricity to power a neighborhood, small town, university or even an island like Kauai.
Grid storage is making people's lives easier (and cheaper) by allowing communities to unhook themselves from the utility power grid. In some cases, it's also providing an incentive for switching to renewable energy sources, which tend to dry up either at night (solar) or during the day (wind).
"It's a major step forward," said George Crabtree, a senior scientist at the Argonne National Lab and an expert in battery technology.
"If you have distributed storage on site, you can then custom design how electricity services are delivered to you."
Tesla has already installed 30 of its "Powerpack" lithium-ion units next to a solar farm near the town of Norwich, Conn. By connecting a solar farm and a series of big batteries, the local utility can provide 100 percent solar power for 725 homes. That's a lot more efficient and cheaper than 725 homes with individual solar panels.
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SolarCity is also installing grid storage and batteries on Kauai in Hawaii, which now has enough storage to power 5,000 homes. Crabtree says that Tesla and SolarCity are providing the means for communities to make and store their own power.
"There's an opportunity for individual homeowners or buildings to customize for themselves to design what they need," Crabtree said. "There's another opportunity for a third-party aggregator to come in and design the battery for your neighborhood and operate it, and it will still be cheaper than what we are building now."
Musk isn't the only solar-battery entrepreneur out there. In May, French energy giant Total acquired Saft Group, which makes nickel and lithium batteries for transportation and civil and military electronics.
U.S. utilities are also looking at the benefits of setting up storage by battery. New York's ConEdison decided to go with a $200 million grid storage project instead of spending $1 billion to rebuild an aging substation to power Brooklyn and Queens.
Green Charge Networks is working with ConEdison to form a "virtual power plant" that taps into energy storage units at schools, apartment blocks and commercial buildings, many of which will have solar photovoltaic panels as well. The idea is to save 52 megawatts of electricity.
Green Charge is also working with utility PG&E to provide distributed energy storage to residents of San Jose, Calif.
"Storage can make the grid more resilient," said Ravi Manghani, GTM Research's director of energy storage, who likened battery storage to a Swiss Army knife that can also be pulled out in case of emergency.
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"In Florida, for example, with its hurricanes and storms, if part of the grid goes off because of a pole crashing, we've never before had a resource that can draw a line or circle on those regions and be able to isolate it and keep the rest of the power grid operating."
Of course, for many communities, it's still too expensive to store electricity in giant battery packs. The price of lithium-ion batteries has dropped, but still remains high, according to Crabtree. And new technologies using lithium-sulfur or lithium-air chemistries have a lot of promise but are still being tested.
"The price has to come down a lot for it to become an economic no brainer," Crabtree said. "That would make deployment soar. We are not there yet. It may require the next generation of battery."
Still, for now, homeowners and ratepayers will slowly see the benefits of these big batteries and virtual power plants in both lower bills and more reliable service, according to Matt Roberts, executive director of the Energy Storage Association, an industry group based in Washington.
"More and ore people will interact with (grid storage) whether they are aware of it or not," Roberts said. "Some of this will be an invisible revolution."
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