ARI SHAPIRO, HOST:
All month, we've been talking about how technology can help slow climate change. And today, that brings us to batteries - not the kind that powers your cellphone, or even your electric car, if you have one. We are talking about batteries that are way bigger - big enough to store all the solar or wind energy you would need to power a city, for example.
Let's bring in Yet-Ming Chiang. He is a material science professor at MIT and founder of several battery companies.
Welcome to ALL THINGS CONSIDERED.
YET-MING CHIANG: Thank you, Ari. It's great to be here.
SHAPIRO: So start with the basics. Explain why batteries are such an essential part of moving to clean energy.
CHIANG: Well, the trend that we are all trying to take advantage of is the fact that renewable electricity - primarily wind and solar - has become the lowest-cost form of generating electricity in many parts of the U.S. and in the world. But the problem that we have is that renewable electricity is not dispatchable. And by that term, we mean we can't call on it for more power when we need it. You simply can't ask the sun to produce more solar power in a given time, or for the wind to blow harder.
SHAPIRO: And batteries are the solution to that problem.
CHIANG: That's right. The ability to store energy makes our electricity more dispatchable and more reliable over longer periods of time.
SHAPIRO: Billions of dollars have been spent on trying to create this technology, and only now are we just starting to see batteries alongside solar and wind farms. Do you think this problem can be cracked? And if so, how soon?
CHIANG: Well, in some parts of the U.S., for example, where solar electricity is already very predictable - in the Southwest, for example - the cost of lithium-ion batteries is already at a point where the combination of solar - generation solar panels and lithium-ion batteries can produce reliable electricity at a cost below that of our conventional fossil-fuel-generated electricity.
But the issue is that not all of the U.S., and certainly not all of the world, has that level of predictability. That's where the problem becomes much harder.
SHAPIRO: I know the cost has been prohibitive for a long time, and it's been coming down recently. When do you think this technology will actually be reasonably affordable in a lot of places?
CHIANG: Yes, I think the answer to that question really depends on what the variability in the electricity generation is that we need to cover. Is it just a few hours of the day, for instance in Arizona, or is it a few days or up to a week, right? Today, an electric vehicle battery pack using lithium-ion batteries costs us about $200 a kilowatt-hour. Over time, we can see that dropping to a hundred or somewhat less than that.
But with lithium-ion batteries, it's difficult for me to imagine the cost getting down to, let's say $10 or $20 a kilowatt-hour. It turns out that's the price range we need for storing electricity for the grid over several days. And in order to accomplish that, we really need to look at other battery materials other than lithium-ion batteries.
SHAPIRO: So lithium-ion batteries use lithium. You're looking for something other than lithium - something else that can store this energy?
CHIANG: Lithium-ion batteries use not only lithium, but they also use nickel. They use cobalt. They may use iron and manganese. And all of these elements have a cost to them. But what we're looking for are batteries that can use either metals or other elements that are much lower-cost, and an example of that would be sulfur. In fact, one of the ironies is that fossil fuels, which we're trying to get rid of, is one of the great sources of sulfur...
SHAPIRO: They produce sulfur, yeah.
CHIANG: ...Through refined petroleum, refined natural gas. And one of the waste products, actually, is sulfur.
SHAPIRO: You're going to have some stinky batteries.
CHIANG: Well, yes, hydrogen sulfide - we've got to keep that contained.
SHAPIRO: Now, I introduced you as somebody who has founded several battery companies. Is that an indication of just how much risk and volatility and how many unknowns exist in this field right now?
CHIANG: Well, these are new technologies that require a highly focused effort that's well-funded in order to try to achieve the kind of breakthroughs that we're looking for. I would call it, you know, a difficult business. Around MIT, we call it hard tech. It's one of the best examples of, you know, hard tech. It may take a number of years to get there.
SHAPIRO: We've talked about the urgency of addressing climate change. Does that translate to a sense of urgency in the field of battery development? Do people feel like there's a lot of pressure to come up with something good, cheap, fast?
CHIANG: Absolutely. We know that our time is limited for solving this problem. And so we are dedicated to carrying out even basic research with much greater urgency than in the past.
SHAPIRO: That is MIT professor and battery entrepreneur Yet-Ming Chiang. Thanks for speaking with us.
CHIANG: Thank you very much.
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