Tesla’s new batteries may be harder on the environment than you think
Tesla’s announcement in April that it would be moving into commercial and residential energy storage was met with almost unanimous applause. The reality is not so clear-cut
Tesla Motors made waves in April when it announced the launch of Tesla Energy, a new business unit that will provide lithium-ion batteries to homes and businesses. Tesla CEO Elon Musk described the potential of a world entirely powered by batteries charged with renewable energy. The media lapped it up, as did consumers, who preordered Tesla’s home battery solution, Powerwall, in droves.
But energy storage experts remain unconvinced. Even Panasonic – supplier of the lithium-ion cells that form the foundation of Tesla’s batteries, and partner on the company’s forthcoming battery factory – calls Musk’s claims hyperbole.
“We are at the very beginning in energy storage in general,” says Phil Hermann, chief energy engineer at Panasonic Eco Solutions. “Most of the projects currently going on are either demo projects or learning experiences for the utilities. There is very little direct commercial stuff going on.
“Elon Musk is out there saying you can do things now that the rest of us are hearing and going, ‘really?’ We wish we could but it’s not really possible yet.”
Musk’s optimism might in part be driven by necessity. The Nevada-based battery factory, called the “Gigafactory”, once completed will have a production capacity that far outstrips the demand produced by Tesla’s vehicles. What to do with all those extra batteries? Sell them in the residential and commercial markets.
It also solves another Tesla problem. The majority of the company’s automotive customers want to be able to rapidly charge their cars at home, but the systems that enable that sort of charging are a major energy suck. Utilities don’t like them, and in many cases won’t allow them. Solution? Charge a Powerwall, then run your electric-vehicle charger off the stored energy.
“It’s a smart business move, and it might be a commercial success, but as a scientist I don’t think what Tesla’s proposing is a good solution,” says Tom Milnes, energy storage expert and CEO of Open Water Power, a Massachusetts Institute of Technology spin-off commercializing a fuel cell for use in naval drones. It’s not a Tesla competitor.
Lithium-ion batteries just won’t store the amount of energy required to be as useful as Musk promises, says Milnes: “Personally I think the Tesla factory producing hundreds of thousands more lithium-ion batteries is really short sighted because those batteries are just never going to hold the amount of energy we need them to.”
Despite all the talk about batteries storing solar energy, renewable energy storage is currently not the primary function of Tesla’s pilot program. Jackson Family Wines (JFW), a family owned and operated company with vineyards and wineries worldwide, hosted the largest installment of Tesla commercial energy storage units during the company’s testing period. While JFW has invested heavily in solar in California, it did not use the Tesla unit to store solar energy. “We’ll eventually use it for solar; we’re excited to test that,” says Julien Gervreau, senior sustainability manager at JFW. “Right now it’s designed for peak saving, so we charge them at night when the grid is stable and electricity is cheap and discharge during the day.”
John Jung, CEO of Greensmith, a supplier of turnkey energy storage systems, says this application is the most common in energy storage, with the majority of large-scale customers being more interested in reliability and cost reductions. The ability to make renewable energy more viable is typically a secondary benefit. “The renewables aspect is still incredibly important, though,” he says. “Even if it’s a secondary thing, it can make a huge difference in terms of a project being [return on investment] positive or negative.”
But even as Tesla’s batteries promise to reduce tailpipe emissions, more direct environmental concerns surround the current boom in lithium-ion batteries. As hundreds of thousands more of these batteries hit the market, the problems that come with lithium mining, battery lifecycles and recycling loom large.
In a 2013 report, the U.S. Environmental Protection Agency’s Design for the Environment program concluded that batteries using nickel and cobalt, like lithium-ion batteries, have the “highest potential for environmental impacts”. It cited negative consequences like mining, global warming, environmental pollution and human health impacts.
While Tesla declines to comment on the particular chemistry it uses, representative Khobi Brooklyn did list nickel as one of the components of the company’s batteries, and lithium is also obviously a component.