Inside Clean Energy: In a Week of Sobering Climate News, Let’s Talk About Batteries

The release of the latest Intergovernmental Panel on Climate Change report showed the magnitude of the challenge of addressing climate change in time to stop its worst impacts, and the failure of leaders to adequately respond to decades of warnings.

In covering the clean energy economy, I get a close-up view of some of the potential alternatives to the continued burning of fossil fuels and get to talk to the people who do research and build businesses that support those projects.

Some of the most exciting developments have been in alternatives to lithium-ion batteries for grid storage, with researchers seeking low-cost ways to store electricity from wind farms and solar arrays. The combination of batteries and renewable energy holds the promise of providing electricity around the clock and replacing fossil fuel power plants.

Right now, the energy storage market is dominated by lithium-ion batteries, which charge and discharge in cycles of up to about four hours. But lithium-ion batteries have some down sides, including the use of rare and expensive materials like cobalt, and components that can be highly flammable. 

Companies like Form Energy and Ambri, both based in Massachusetts, have been raising money from investors and talking about their plans to develop long-duration storage batteries. Form Energy, led by a former Tesla executive, is making a battery that uses iron and oxygen as key components, and can run for days on a charge. Ambri, which counts Bill Gates among its major investors, is making a battery with components that include a liquid calcium alloy and molten sodium, and is being designed to run for up to 24 hours on a charge. The company announced a new round of funding this week, which you can read more about below.

Those are just two companies in an ecosystem of start-ups, universities and national laboratories that are preparing for the market that they see on the horizon.

On Monday, the same day the IPCC report came out, I spoke with researchers at a Sandia National Laboratories in Albuquerque, New Mexico, who had just published a paper about their project to develop a molten-sodium battery.

The battery uses sodium that has been heated to its melting point. The battery charges and discharges in a process where sodium ions pass through a ceramic divider.

Molten-sodium batteries, in a form that uses sulfur as a key component, have existed for decades, but they have been limited by high costs tied to the need for high operating temperatures, said Leo Small, the lead researcher on the Sandia project.

The average cost of a lithium-ion battery was $137 per kilowatt-hour of storage last year, according to BloombergNEF, while the price range for a sodium-sulfur battery starts at more than three times that much, according to a 2019 Department of Energy report. 

Companies and research institutions are now developing new variations on molten-sodium batteries. The goal of the Sandia research is to come up with a design that can work at much cooler temperatures and that would cost much less than today’s lithium-ion batteries.

“We think that by driving down the temperature we can get a lot of cascading cost savings,” Small said.

So far, the researchers have succeeded. Their battery works at about 230 degrees Fahrenheit, which is much cooler than existing molten sodium batteries that operate at more than 500 degrees Fahrenheit. Because of its cooler temperature, the battery needs less insulation and can work with thinner wires.

The hope is that this kind of battery could become an inexpensive option for utilities and project developers that want to build large energy storage systems. The battery in the Sandia project would be able to discharge for eight to 16 hours, Small said.

I asked Martha Gross, another researcher on the project, how she explains what she does to friends and family.

“I tell them I work on really big batteries with cheap materials, for hooking up to the electric grid,” she said. “These are batteries that can be used with solar or wind to replace coal plants, or replace generators during emergencies like hurricanes knocking out the power.”

The Sandia project had some tense moments because of the coronavirus. The researchers needed to stop their work for about a month and they let the battery cool down and then freeze. They had hoped that their design could easily restart, but didn’t know for sure.

Then, when they got back into their lab, they heated the battery to its operating temperature. Gross said she was “decidedly nervous” about the outcome, but found that it worked perfectly.

The molten-sodium battery design remains in the research phase, with any commercial use still five to 10 years away, Small said.

A 10-year timeframe is on the minds of many of the people developing clean energy technologies, part of the growing use of 2030 as a benchmark year for making substantial progress in moving away from fossil fuels.

Last month, U.S. Energy Secretary Jennifer Granholm announced a new goal to reduce the cost of long-duration energy storage by 90 percent within 10 years. Her office defines long-duration storage as systems capable of discharging electricity for at least 10 hours at a time.

The baseline cost for that goal is the 2020 average for lithium ion batteries, which was $137 according to BloombergNEF. One-tenth of that would be about $14 per kilowatt-hour, which is extremely low.

If researchers can reach that goal, or even come close, electricity from renewables paired with batteries would be much less expensive than fossil fuels, and the transition to clean energy would gain formidable momentum on economic factors alone.

I’m not saying that’s going to happen, but just the possibility is enough to chase away some of the pessimism many of us are feeling this week.

Other stories about the energy transition to take note of this week.

Ambri Announces New Round of Funding to Develop Battery: Funders continue to put money into battery start-ups, as shown by Ambri’s announcement this week that it had raised an additional $144 million. The latest round of funding is despite Ambri not meeting previous targets for having its product ready for deployment, as Eric Wesoff reports for Canary Media. “Ambri joins a growing crop of revenue-free battery unicorns,” Wesoff writes, making light of the disconnect between the high levels of investment by people like Bill Gates, and the almost complete lack of sales.

Biden Tightens Auto Emissions Standards and Sets New EV Goal: President Joe Biden made some big moves to advance clean transportation last week, with his administration submitting an updated rule for vehicle emissions standards and his signing of an executive order that sets a target of emissions-free vehicles being 50 percent of new-car sales by 2030. The new emissions rules are a partial replacement of the Trump administration’s rollback of Obama administration rules, as I reported with some of my colleagues at ICN. He framed the goal and the emissions standards in terms of international competition, saying that the future of the automobile industry was electric, “and there’s no turning back. The question is whether we’ll lead or fall behind in the race for the future.”

Many More Coal and Gas Plants Risk Becoming “Stranded Assets”: Policies that support renewable energy are contributing to market factors that are likely to strand about $68 billion in investments in coal and gas power plants, according to a new analysis from S&P Global Market Intelligence. This means that the companies that spent money on the plants would be unable to recoup their investments. Some of the biggest risks are in newly built natural gas plants that are on track to be used much less than developers had anticipated, which reduces the return on investment, as Emma Penrod reports for Utility Dive.

Inside Clean Energy is ICN’s weekly bulletin of news and analysis about the energy transition. Send news tips and questions to dan.gearino@insideclimatenews.org.