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A zinc-based battery storage installation from New Jersey-based Eos Energy.

Zinc-based energy storage project coming to San Diego area

ROB NIKOLEWSKI
JAN. 8, 2021 5 AM PT
Original Article
$20 million project between EnerSmart and Eos Energy

A battery storage project aimed at adding more carbon-free power to California’s electric grid is about to launch in the San Diego area.

EnerSmart, a renewable energy company based in San Diego and Boulder, Colorado, has signed a $20 million order with Eos Energy to install 10 facilities of 3-megawatts each that will employ zinc battery storage technology. Each of the projects will supply enough energy to power about 2,000 homes.

Seven of the 10 storage sites will be located in San Diego County and EnerSmart plans to have each one up and running by the end of the year.

The deal will provide at least 30 megawatts of utility-scale battery storage capacity to the grid. Over the next 24 months, EnerSmart has an option with Eos Energy to double both the size of its investment and the number of the project’s battery storage sites.

“If there’s a need for more, then we’ll do more,” said James Beach, managing partner at EnerSmart.

The seven facilities already under contract will be installed in Chula Vista, El Cajon, Imperial Beach, Lakeside, Ramona, along with two in San Diego.

“What makes our projects unique is that because they are 3-megawatt, the energy can go into lower voltage distribution lines so we’re really providing voltage support to the local communities,” Beach said.

The electricity and voltage support discharged from the 10 batteries will go to the California Independent System Operator, or CAISO, the nonprofit corporation that manages about 80 percent of the power grid in the state.

Energy storage is taking on a larger and more pivotal role in California’s power mix. Under the state’s Renewable Portfolio Standard, 60 percent of California’s electricity must come from renewable sources by 2020. In 2045, 100 percent is slated to be derived by sources that emit zero carbon.

Solar energy is so abundant in California during the day the CAISO sometimes has to send the excess to adjacent states like Arizona or curtail it all together. But when the sun goes down, solar production disappears.

Storage can help solve the problem by taking the excess energy solar generates during the day, save it with battery storage and then send it back to the grid at night, or at other times when the electric system needs it.

Any extra megawatts of power could have also come in handy last summer when an extreme heat wave in mid-August resulted in California experiencing its first statewide rolling blackouts since 2001.

The California Public Utilities Commission expects about 2,100 megawatts of storage added to the grid statewide by August. For perspective, the peak demand on the CAISO system on Thursday came to 26,221 megawatts.

“We’re excited to help and this is a way to make our energy value chain greener,” said Joe Mastrangelo, CEO of Eos Energy, which is based in Edison, New Jersey and manufactures its zinc battery storage systems in Pittsburgh.

The growing battery storage market is dominated by lithium-ion, the same technology that powers hundreds of millions of smartphones, as well as plug-in electric cars. In 2017, San Diego Gas & Electric opened a 30-megawatt battery storage facility in Escondido, at the time the largest single lithium-ion battery project in the world.

Looking into zinc-based batteries as an alternative, Eos has invested millions to develop its Zynth technology.

Lithium-ion batteries have battled issues with excessive heat. In 2019 a battery installation at an energy storage facility in the town of Surprise, Arizona, exploded, injuring nine first responders. On the electric car front, there have been reports of older model Teslas catching fire, incidents some experts say is related to the car’s batteries.

Mastrangelo says zinc-base battery systems are safer because they don’t use the complex heating and air conditioning systems that lithium-ion batteries employ. He also touts zinc batteries’ ability to be recycled and flexibility when it comes to charging them up and discharging power.

close-up look at the EOS Energy Znyth battery technology used in energy storage installations

“Our system loves to go from 100 percent down to zero,” Mastrangelo said. “We could sit at zero for extended periods of time and not damage the system. And we can discharge anywhere from three to hours to 12 hours, depending on the use-case.”

The standard duration time for battery storage systems is about four hours.

The knock on energy storage is their relatively high cost compared to conventional sources of energy. In the early 1990s, for example, lithium-ion battery projects cost about $10,000 per kilowatt-hour. Prices have gone down dramatically, though, with the Brattle Group consultancy last year reporting prices as low as under $400.

The industry’s breakthrough price is generally considered to be $100 per kilowatt-hour.

Beach of EnerSmart estimated the price for his company’s 10 projects with Eos will come to about $300 per kilowatt-hour. “We’ll be the ones absorbing that,” he said.

The first of the seven San Diego County installations scheduled for completion will come in El Cajon. EnerSmart has leased a location at the East County Transitional Living Center, which provides services to those in need.

“We just love that we can put these projects on sites like that,” Beach said.