1.5GWh of ‘Made in America’ zinc batteries joining Texas, California grids from Eos Energy Storage

By Andy Colthorpe
September 1, 2020
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Eos’ zinc hybrid cathode battery energy storage systems at a pilot project hosted by Duke Energy. Image: Duke Energy.

Agreements to deploy 1GWh of novel aqueous zinc battery energy storage in Texas and 500MWh in California have been struck by technology provider Eos Energy Storage, marking a massive scale-up in expected installations for the systems.

Eos Energy Storage said in a press release yesterday that its long duration zinc hybrid cathode batteries, which are best suited for 4-6 hour discharge but have the flexibility to go to higher power and longer run-times through de-rating power, have been ordered by ‘technology agnostic’ power producer International Electric Power for 1GWh of projects to be connected to the grid run by the Electricity Reliability Council of Texas (ERCOT).

A second customer, Carson Hybrid Energy Storage (CHES), has ordered Eos’ zinc batteries for the full capacity of a 500MWh energy storage facility in the Los Angeles Basin. CHES will use the zinc batteries to store surplus solar that otherwise would be curtailed and unused, while also easing congestion on transmission lines. The project will be preceded by a 1MW pilot to be constructed next year.

CHES president Peter Reardon said that the fire safety of Eos’ technology was a big factor in their selection, as was the ‘Made in the USA’ tag that accompanies the battery systems – Eos has partnered with US nuclear technology company Holtec to create a manufacturing joint venture (JV) called HI-POWER. Alongside the order announcements, Eos said Holtec has invested a further US$10 million into the JV on top of an initial US$12 million it put in last year.

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Eos not only makes and supplies the batteries but also the integrated AC Battery Energy Storage System (BESS) that the customers require to connect them to the grid and to other energy resources such as solar and wind. The company claims its battery systems are non-flammable as well as made from widely-available, recyclable materials and as far back as 2017 was claiming solar-plus-storage with 4-hour discharge could be possible for as low as US$0.10 per kWh using the technology.

With California’s well-publicised recent woes over energy supply reliability, Reardon and his team believe the zinc aqueous battery storage can be an important resource. The 500MWh project and a possible 200MWh follow-on to be built later are in the service area of California investor-owned utility Southern California Edison and the developer said it has received support from the utility to “maximise the benefit of an existing interconnect” to allow it to be located in the LA Basin area.

Meanwhile, Eos will begin manufacturing, designing and delivering the multiple systems ordered by Pittsburgh-headquartered power producer International Electric Power (IEP) in the third quarter of 2021.

IEP is yet to identify the exact locations where the systems will be sited, but the company’s CEO Peter Dailey said that the ERCOT market “offers perhaps the most interesting opportunity for battery plays in the United States, including hourly energy arbitrage, ancillaries and congestion revenue rights”.

Multiple recent project announcements including the state’s biggest standalone projects planned at 100MW/100MWh appear to bear that out, while the company behind the state’s biggest project to date, a 42MWh project in operation now for 18 months said an independent auditor review had confirmed the system’s technical and economic performance to have been an “all-round success”.

Company ‘on track’ to go public

Eos has been able to get pilot projects deployed in multiple territories including Latin America and for US energy holding major Duke Energy in the past few years, and recently received an order for a 4MWh project at one of the world’s largest oil refineries, in Greece. To date, the company’s biggest single announced deal had been for a 10MW/40MWh system ordered by developer Convergent Energy + Power in 2015 for a California project still awaiting confirmation of go-ahead.

The company is targeting going public, through a merger with B. Riley Principal Merger Corp. II, a special purpose acquisition company created by financial services company B. Riley Financial. Eos CEO Joe Mastrangelo said the companies are “on track to imminently execute a definitive agreement”.

“The business combination will allow Eos to achieve its long-term potential and fuel our mission. Our groundbreaking aqueous zinc battery technology is well-positioned to be a leading solution to meet short-term and long-term demand for safe, sustainable, and scalable long-duration clean energy,” Mastrangelo said.

Eos Energy Storage was among the technology providers discussed and profiled in our feature article ‘Contenders: Long duration energy storage technologies, and who’s behind them’.

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