Redwood Materials has long dominated EV battery recycling, but what if they could drain every last drop of energy from those batteries before recycling them? I talk with the company’s CTO, Colin Campbell, about Redwood Energy, a new division doing just that by deploying used batteries as grid-scale storage at a massive scale. This isn’t just a side project; it’s a plan to turn a massive wave of incoming used batteries into a key resource for the grid.
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David Roberts
Hi everybody, this is Volts for October 22, 2025, “Can ‘second life’ EV batteries work as grid-scale energy storage?” I’m your host, David Roberts. Redwood Materials started recycling lithium-ion batteries before it was cool, before it was profitable, and before there were very many lithium-ion batteries to speak of. In the five years since, it has grown and scaled to capture the overwhelming majority of the booming automotive-battery recycling market in North America.
Earlier this year, it spun off a new division called Redwood Energy. The idea is simple: it is going to hook the EV batteries it receives up to large arrays that serve as grid-scale energy storage. That way, it can drain every last bit of useful life out of them before it recycles them.
So-called “second life” batteries have been discussed for many, many years, but this is the first time they have been deployed at appreciable scale. Redwood has built an off-grid facility where 20 megawatts of solar panels are powering 63 megawatt-hours of second life batteries that feed into two one-megawatt data centers.
Today, I am going to chat with the company’s CTO, Colin Campbell, about why Redwood hatched this initiative, how the costs of second life storage compare with the rest of the storage market, and how big he thinks this side of the business could ultimately get.
All right then, with no further ado, Colin Campbell, welcome to Volts. Thank you so much for coming.
Colin Campbell
David, thanks so much for having me. Pleasure to be here with you.
David Roberts
Before we jump in, let’s back up a little bit — I should have probably mentioned in the intro you are, in certain circles, semi-famous. Colin Campbell worked at Tesla for many, many years — 17 years — one of their lead engineers. So a big role in designing and growing Tesla. So maybe you could just say briefly what it is that pulled you over to this side of things?
Colin Campbell
Yeah, I was really excited when I joined Redwood to take some of the same philosophies and approaches and really, how should we say it, sort of the ethical impetus that brought me to Tesla and to deploy it in another part of the world. So instead of in consumer devices, cars, in industrial and industry, in things like the metals markets, novel material manufacturing at scale in the US. These are things that I think we all feel have withered a little bit over the last 20, 30 years in the US, and there’s a tremendous opportunity to apply some of the same lessons that we used at Tesla to those industries.
David Roberts
Was it 2019 that Redwood got underway?
Colin Campbell
Yes, that’s right.
David Roberts
And when Redwood started, there were not that many EV batteries around. So you guys have been recycling all kinds. Basically just taking all lithium-ion batteries. Is that right?
Colin Campbell
Yeah. If you’ve got a lithium-ion battery, we will recycle it for you. So we’ll take your AirPods, your toothbrush, we’ll take that laptop, cell phone, all the way up to EVs.
David Roberts
When did automotive batteries become the majority of your input by volume?
Colin Campbell
That is a good question.
David Roberts
Was it recent or was that early on?
Colin Campbell
I would say the transition to EV batteries dominating what we received, it’s been in the last year or 18 months.
David Roberts
So the front edge of a very large wave of batteries has begun to arrive?
Colin Campbell
Yeah, the wave is out there, it’s coming. The waters have finally started to arrive at the beach here.
David Roberts
So then comes this idea — and I have to think that someone at Redwood has had this idea in the back of their minds for a while — this idea of you’re getting all these batteries and then you’re just sucking the life out of them before you recycle them. It seems quite logical, but it raises all kinds of questions. So the very first question, I think the most important, because people have been discussing second life batteries for a long time, and always the barrier that keeps people away from it is batteries are very heterogeneous.
They come in. There are lots of different chemistries, there are lots of different wear and tear, states of wear and tear, how much life they have in them. You just get a huge variety of batteries. Making all those batteries work together has been the trick. And so when I heard this announcement from Redwood, I was like, “Oh my God, how’d they solve that problem?” And I went and looked and all it says on the site is, “Hey, we solved that problem.” So I’m very curious. Like, I thought that was an extremely difficult problem, but apparently you just hook all these different batteries up to this little box, this little box that you’re calling the universal translator, and voila, they all work together. So can you tell us a little bit about how you did that?
Colin Campbell
Simple as that. Yes. No, you’re absolutely right. And the idea of a second life battery in a second life energy storage system has been out there for a long time. I think you nailed one piece of it, which was that we weren’t really seeing those batteries come back for, originally, recycling, and now for second life in appreciable volume until really recently. We know it’s inevitable that they’ll come back, but it just hadn’t started to happen yet. And the other thing that’s made this practical — and more than practical, a good business for us — is a couple of realizations we had.
So one is that electric vehicle batteries are incredibly robust, and grid-scale energy storage is a relatively pastoral life for those batteries — it’s really like putting the old horse out to pasture. So what that means is you don’t have to do much to them. They’re mechanically made for salt spray and vibration and being underwater, and they’re electrically made for fast charging, for merging onto the freeway, for high performance.
David Roberts
They’re very high-end.
Colin Campbell
Yes, exactly.
David Roberts
I don’t know that people understand, one, how high end they are, or two, how big they are — capacity-wise, they’re huge. And then there’s three, sort of how big they are physically. I mean, one of the things that sort of haunted me as I was reading about this, and this is for years, when I think automotive battery, my brain wants to think about the size and shape of the normal —
Colin Campbell
12-volt lead-acid guy.
David Roberts
12-volt battery, that square. And I was like, “Oh, those little square boxes. Well, those will be easy to stack.” But of course, an actual EV battery is this big, unwieldy, odd-shaped thing that is also heavy. You have to carry them around with forklifts.
Colin Campbell
Yep. So because they’re so awkward and big, if you’re going to repurpose them and have a profitable business doing that, you really can’t spend a bunch of labor on it. So the important thing for us was, don’t disassemble it, don’t mess with it, really use it as it is.
David Roberts
That’s key here. You’re not getting at the cells, you’re not tearing it down and using the cells, you’re just — it’s just the battery itself. You’re just plugging the battery itself, laying it on the ground and plugging it in.
Colin Campbell
Yeah, there’s a little bit more magic to that, but that’s the core of it — do as little as possible, make it really, really simple to keep it cheap and resilient and flexible for the, what you said, the wide variety of packs that we get.
David Roberts
And we should say another barrier to making this business work was the incredible logistics involved in gathering batteries, which, of course, you guys are already doing.
Colin Campbell
Yeah, it’s an underappreciated challenge of the recycling business, which is just gathering all the batteries. It’s an incredibly diverse and heterogeneous set of companies, set of individuals, set of utilities, and municipal agencies that collect them. And our commercial team has just crushed it, really, in making it so that all those batteries come to us.
David Roberts
What’s the percentage now?
Colin Campbell
It’s north of 70 or 80%.
David Roberts
So is that 80% of the batteries that get recycled or do you think it’s 80% of all lithium-ion car batteries?
Colin Campbell
It is of the lithium-ion batteries. So more than just car batteries that get recycled in the US.
David Roberts
So you’re the bulk of the recycling business. But you didn’t actually answer the core of the question, which is — I mean, I’m sure the actual answer is some sort of software gobbledygook that I wouldn’t understand — but what is it that made it possible for you, you guys, to figure this software out when other people have failed?
Colin Campbell
Yeah. So there are two parts, like we said: One is this mechanical simplicity and the other is what you referred to earlier, this box that we’re calling a universal translator. So what is that? That is something that our really strong in-house power electronics team built. It is a way to make sure every one of these unique snowflakes of a pack gets individual care and feeding. So it’s a way to control the voltage, control the power for each pack, depending on its own unique state of health, its own unique state of charge. Also to talk the language of any pack.
So if you’ve got 50 different pack manufacturers, they all talk 50 different languages, the content is kind of similar —
David Roberts
I was curious about that, are you sort of able to generalize at all or are you really sort of having, “Well, here’s NMC language. We got to program that in.” Is there any sort of commonality among batteries or is it really just bespoke, you got to program every single individual one in there?
Colin Campbell
It’s pretty bespoke. The content is the same. All battery packs want to talk about is cell voltages, cell temperatures, and pack currents. But the languages are pretty different.
David Roberts
Interesting.
Colin Campbell
So that’s been a real effort and a real successful effort by our software team to abstract that away and make it so that at the high level we just have a battery.
David Roberts
So I’m curious just how agnostic it is. Can you say with confidence that any EV battery on the market, if you wear it out in your car, you can plug it into this thing? Is that categorical?
Colin Campbell
It’s never, never 100%. But we’ve put a lot of effort into making sure we’re in the high 90s. So this universal translator that we built, it’s ready for battery packs anywhere from 200 to 900 volts, for example. So we know more modern cars are higher voltage, semi trucks are higher voltage, Cybertrucks are higher voltage. And then also we’re agnostic to chemistry, so LFP, high nickel, we can take it all.
David Roberts
That is just wild. So congrats to your software team. It actually raises the question, which is, I’m wondering, like, how modular is this? It seems like the box, the software is the key thing. So if I, for whatever reason, had one of these boxes and I’m like, I don’t know, I run an automotive garage or something and I just happen to have three or four spare EV batteries in my backyard, could I hook them together and treat them like one battery, just using this thing? Like how, how small can it get, I guess is the question?
Colin Campbell
Yeah, you hypothetically could. I’d never thought about it, to be honest. But there’s no reason you couldn’t make a 200 kilowatt-hour site using this same piece of technology.
David Roberts
So it’ll scale down as far as you would ever want?
Colin Campbell
It will. I’ll say that’s not the question we most commonly get. Usually people want to know how big can you go and how fast can you go?
David Roberts
Yeah, yeah, yeah, well, we’ll get there. But you know, I love me some distributed energy, so I’d love to think about who could do this on site, basically. So you get the batteries and you assess them presumably to see if they’re suitable for this. Sort of like, what’s the criteria and how many batteries make it through?
Colin Campbell
Yeah, the assessment, I think it’s less of an intense torture test than most people imagine. And the reason for that is you don’t need that much cycle life out of a used battery in order for it to make economic sense to put it into service. So you don’t really need perfect understanding of its state of health. You just need to know it’s good enough. And so that’s something — we’ve built some specialized hardware to do that. It’s less than a minute per battery.
David Roberts
Oh, so you get it, you plug it in, you get a thumbs-up or thumbs-down.
Colin Campbell
Red light, green light.
David Roberts
And how many batteries get sort of rejected versus accepted, do you know?
Colin Campbell
We do know. I’ll have to say we’re constitutionally sort of incapable of rejecting things. So first pass, it’s high 90s that we’re accepting.
David Roberts
Ah, so most batteries then will have some juice left.
Colin Campbell
Most batteries are good enough, and that doesn’t mean they’re great, but they’re really good enough to deploy. And then we’re always looking at that fraction that got rejected and just saying, “How can we squeeze a little bit more utility out of those?”
David Roberts
Maybe this comparison you don’t have in the top of your head, but relatively speaking, for a given battery, say an NMC battery, what is the value of this remaining capacity you’re getting out of them versus the value of the metals that you recover out of them?
Colin Campbell
Yeah, well, obviously it varies and we’re learning, but equal to or greater and maybe several times greater.
David Roberts
Oh, interesting. So this is not a marginal bit of value creation. Then you’re getting, you’re 2x-ing the value you get out of these batteries by doing this?
Colin Campbell
Something like that. Which is like, “Oh my goodness, look at this utility that we were rushing into the recycler. Let’s go and take a detour and capture it.”
David Roberts
Right, right. So tell me just a little bit about, from an engineering perspective, how you design a system when you know that these batteries, let’s say relative to a typical grid-scale battery installation, you’re going to be mucking with these a lot more. You’re going to be adding them and removing them more frequently than a typical battery installation. How do you design around that to try to keep that cost — because I’ll just say up front, like when I first heard about this, and I’m sure a lot of people say this, like my first thought is just like, “That just sounds like a lot of logistics, like a lot of people, a lot of forklifts, a lot of space, just a lot of logistics.”
So it must be clear to you that you’re getting more value out of it than the logistics. But how are you trying to minimize the logistics of being this active — taking things in and out?
Colin Campbell
Yeah, well, the short answer, and maybe not that helpful, is you design for it. So you know that you’re going to have to swap packs more often than in a brand new energy storage site with new cells. And so you provision for that in your design. So, yeah, there’s some small amount of forklift traffic. You make sure it’s really simple to access packs, that it’s really simple for an operator to connect and disconnect packs, to lift them, to move them. And I think one piece of this that is related to that is that these sites are slightly lower energy density than maybe a brand new purpose-built energy storage site. And that really eases service.
David Roberts
How do you mean? Like, what do you mean safety-wise?
Colin Campbell
No, no, just in terms of the megawatt-hours per acre. They’re a little more spread out, and part of that is service and planning for service.
David Roberts
So you just have to literally physically lay them on the ground. You have to space them out enough that you can get to them, basically?
Colin Campbell
Yeah, it’s actually — I think of it less as a requirement of second life energy storage and it’s more one about like what is the value of a really dense energy storage site? For some sites it’s really important: if you’re in a city, if you’re close to some infrastructure where land is expensive, it’s really important. But in many, many sites it’s less important and you would actually get a lower cost dollars per kilowatt-hour installed with less energy density. And that was one important realization.
David Roberts
Because of lower labor costs, because of easier — it’s just easier to use, easier to update.
Colin Campbell
Just simpler. The closer you pack cells together, the more careful you have to be because they do contain energy.
David Roberts
Well, let’s talk about safety then. Because I was going to get to that later, but I’m assuming that, like, because these are spaced out so widely and they’re just sort of individually attached, it’s kind of difficult for me to imagine any sort of large-scale fire or any danger really. Is there safety? What is the, what are the safety considerations here?
Colin Campbell
So top of the list for us, of course, designing this thing is safety. And our guiding light has always been passive safety. So if you do have a fire for whatever reason, that it stops on its own, that no fire response is needed, no sprinklers are needed, you’re absolutely welcome to. We encourage people to do that, but it’s not necessary. So it’s a passive feature of the system.
David Roberts
So this individual battery that’s hooked up could theoretically catch on fire, burn up, and be done — and that’s it. And who cares, basically.
Colin Campbell
That’s exactly right.
David Roberts
Has that happened? Have you had any thermal runaways yet? I’m always curious what the actual percentage of that happening is.
Colin Campbell
No, we haven’t. It’s really rare. I mean, it’s impactful and it’s important when it does. And I think Moss Landing in particular really sticks in everyone’s imagination.
David Roberts
It really does. That’s why I have to ask this question anytime I talk to a battery company.
Colin Campbell
Yeah. And that’s real. That was a real — that was a bad outcome. But we are designed to avoid anything like that.
David Roberts
How long have you had enough batteries come through yet that you’re able to generalize about kind of what you’re getting out of them? Like, what is the average lifespan of one of these?
Colin Campbell
Yeah, we really don’t know, to be frank. But what we do know is that it’s long enough to be a good business, that if we deploy them for a year, for 500 cycles, something like that, that makes sense. And we know that that’s well within reach.
David Roberts
But presumably this little box is recording lots of information about these. So you are gathering tons of data, presumably tons of data about the performance of these used batteries?
Colin Campbell
Yeah, absolutely. I think we’re going to be the clearinghouse for what actually happens at the end of life for EV packs. But it takes a long time. They’re pretty robust. So even after you have rightfully retired one from your car for being slow and having a short range, there are many, many, many years of capacity remaining at that thing.
David Roberts
80% is like the typical industry — that’s where you sort of cut off the EV battery usefulness. When it gets down to 80%?
Colin Campbell
Yeah, that’s a norm. Depends on the customer. It’s really their choice.
David Roberts
Sure, but 80% is a lot.
Colin Campbell
Exactly.
David Roberts
You sort of already answered this, but I’ll ask it anyway: So right now you’re going to places where land is not at a particular premium. And so there’s no real reason not to spread out, as you say. You might even get a little better unit economics spreading out more. I wonder, do you expect all future second life grid-scale storage to be in places where land is not a premium? Because what I’m wondering is, are there engineering ways to get them closer together? Could you ever figure out how to stack them? Like, they are very spread out.
And like the first thing that came to mind was, if this becomes really valuable and really common, somebody is going to figure out how to squish them closer together. Is that something you think about at all?
Colin Campbell
We do think about it and we in fact have already done it. So our architecture is flexible, so we really work with our customer to understand the value of density to them. And if it’s high, then we can provide a much denser product.
David Roberts
You can do it. Is there stacking? Can you stack them at all? Go vertical at all? Because this is the thing, they just spread out horizontally. And I can’t help thinking, if you could just go up a couple of stories, you could fit so much more.
Colin Campbell
Yeah. There are a bunch of different ways to do it, and it just starts to get a little more complicated. You’ve got to build the tower for them to live in and figure out how to get them in and out. It’s all possible. It all makes sense in certain circumstances, but not all. So we work with the people who are buying these to figure out what makes sense.
David Roberts
Is the idea here that you will be the developer and the owner of the battery in all cases, or are you selling, will someone else own and operate them? What’s the business model exactly?
Colin Campbell
I mean, this industry, there’s probably every business model under the sun available, and we’re open to pretty much all of them. The one thing that is important to us is that we recycle the packs. That’s part of our mission. It’s part of what we think is important to do in North America, and we intend to do that.
David Roberts
But that sort of suggests that the model that makes the most sense is for you to just be sort of having them and owning them and running them the whole time. Or is the idea that you could ship a bunch of these to a separate site, they set up one of these, and then they ship them back to your facility when they’re done with them, but they own them while they’re in the battery?
Colin Campbell
There’s — I’m not trying to be cute — you could imagine a million different ways to structure that sort of contractual relationship. And in the end, the batteries, we still would like to receive them for recycling.
David Roberts
I guess it’s more like the physics or logistics of it. I’m sort of wondering about. Because doing this right next to the plant where they’re recycled makes just a ton of sense. Obviously, there’s very little logistics, but once you have one of these set up in a spot that is remote from the recycling facility, then the fact that packs are coming in and out frequently becomes a little bit more of an issue. Because then you have a sort of a supply chain between you and a remote facility. That doesn’t daunt you at all?
Colin Campbell
You have to think about it. But this is not like rail cars and rail cars of packs going back and forth, even from a giant energy storage site. It’s like a few. And at the beginning, while we are really pioneering this and doing it for the first time — I think it makes total sense for us to do it ourselves. And we will. But I don’t think that’s necessary long term.
David Roberts
So one of the claims your CEO J. B. Straubel makes in his sort of introductory video is that this is going to be cheaper than grid-scale storage with new lithium-ion batteries. And I guess the calculation there is — on one hand, your business model works as is. So you have the batteries from the perspective of this new division basically for free. Like they’re already there. You’re already gathering them. So in a sense, even if they’re lower quality than new batteries, they’re just sitting there. So, in a sense they’re cheaper that way.
But on the other hand, you have all this logistics, you have all these forklifts and trucks and setting up and the space and site and everything else. So I’m just wondering how the costs balance out. Is there an easy comparison between a new second life battery and a brand new battery? Like a cost comparison?
Colin Campbell
Yeah, I think as you pointed out, the cost of energy is low compared to a brand new battery because it’s degraded, it’s been out in the world, it’s not a fresh battery. The balance of system, we’re actually making really important strides there too. So the power electronics, the mechanical assembly, there’s a lot of cost in these sites around what people call the EPC cost — engineering, procurement, construction — civil works, getting the batteries plugged in, wiring the whole thing up. And we spent and are spending a lot of time optimizing sort of the rest of the cost stack.
So not just leaning on the fact that our energy is relatively low cost because it is second life energy, but really pushing hard on power electronics. We have that whole team in-house. Push down the dollars per watt of power electronics, make it a really, really simple, really, really robust thing to deploy. And that’s underappreciated about what we’re up to — it’s not just that the batteries are cheaper, the whole system is simpler.
David Roberts
Well, that’s, I mean, it’s the whole system that first jumped up when I started reading about this. Like obviously that’s where, like, you found an incredibly cheap source of batteries, i.e. a big pile of batteries you already had in your backyard. But like, it’s all, all the costs are the logistics and the balance of system stuff. So you think you have running room there to bring those costs down substantially?
Colin Campbell
Absolutely.
David Roberts
But you can claim that you are beating a new lithium-ion grid-scale battery storage system on the sort of per kilowatt-hour basis already?
Colin Campbell
Yes, we can, and that’s installed over life. So there’s a little bit of pack replacement that has to happen.
David Roberts
Do you have a number? What are you pitching to people when you’re trying to sell this?
Colin Campbell
I do have a number, but it’s enough to make it a really good, great business, I think, is what I will say here.
David Roberts
Okay, but like, sort of legendarily, a new lithium-ion battery grid-scale storage — they sort of will do four hours, some of them will do eight hours. Some people now are pushing the economics because batteries are getting cheaper. They’re pushing the economics out to maybe 12 hours at the outer edge. If your unit costs are that much cheaper, how — what kind of durations do you think you can get given your cheaper system?
Colin Campbell
You’ve actually nailed it there. So because energy is cheaper, the balance of plant, which we are making great progress on, like power electronics, the cost of power starts to become more important. And so we have a real advantage for eight-hour and beyond energy storage. We can play and compete and win at 2-hour and 4-hour on total installed cost over life. But it starts to look really compelling at the longer durations.
David Roberts
Oh, interesting. Can you do 24 hours? The Holy Grail. Could you make something baseload out of this?
Colin Campbell
Absolutely. The original modeling that we did for this was around a 24-hour system. Turning renewables into baseload. Looks really good.
David Roberts
I’ve been told by many very confident-sounding people, Colin, that that’s impossible. So you say you did it. So do you envision the next plant you build and the next one after that — do you envision hooking these up to the grid and having them sort of make money off providing services to the grid, arbitrage, frequency, et cetera, et cetera? Or do you primarily envision doing what you’ve done with this first installation, which is going off-grid? You got solar panels, you got batteries, you got data centers. It’s all hooked up together, it’s all self-contained and running on its own, and does not need one of these very difficult-to-get grid connections.
Which model do you think is going to dominate?
Colin Campbell
We are going to do all of the above. We can and we are doing sites for grid services. Just plug a battery into the grid and help support the grid by participating in the market. We have other “microgrids.” They’re not so micro anymore. They’re many, many, many megawatts.
David Roberts
Go ahead and brag. This one you built? Yeah, it’s Nevada. I forget — it’s the biggest microgrid in America? You are claiming North America.
Colin Campbell
It’s the largest microgrid in North America and it’s the largest second-energy storage site in the world. So that’s like you said at the top, it’s a 12-megawatt AC, 63-megawatt-hour grid supporting about 2 or 3 megawatts of data centers and run by solar. So all the energy comes from another 12 megawatts of solar.
David Roberts
And the grid does not touch it. There’s no transmission grid connection at all?
Colin Campbell
That’s exactly right.
David Roberts
What a beautiful thing. I’ve also been confidently told that those things don’t work economically. Exciting that it is working. And you’ve probably answered this already. But in terms of grid services, you hook one of these things up to the grid, there’s nothing that new batteries can do that these batteries can’t do, right? In terms of frequency regulation and all this kind of stuff. Grid forming, whatever. The kind of things that the batteries and inverters can do.
Colin Campbell
Virtual inertia, all of that. I mean, one of the things that is very topical right now is the data center market, of course, like a giant increase in the demand for power.
David Roberts
Indeed.
Colin Campbell
And there’s just this beautiful symbiosis between energy storage and data centers. Sort of no matter what your primary source of power is. So much of it is the, there’s already huge racks of batteries and uninterruptible power supplies inside the data center. Already these big diesel generators. We can make both of those things obsolete.
David Roberts
So you now have two little data centers running. I mean, the data center company technology that you’re using at this site is also pretty interesting on its own merits. But they’re building basically what they call modular data centers. And I’ve been wondering when someone’s going to do this because everybody, it’s kind of the same arc nuclear went on at first. Everybody’s like economies of scale. Economies of scale. Bigger, bigger, bigger, bigger, bigger, big, big, big. And you’re getting these data centers now that are like small cities, like gigawatt-plus data centers. And I have part of this podcast premise to hunt great faith in modularity and repeatability and manufacturability competing against those economies of scale.
So this company is making data centers at this site in Nevada, is making these basically like containerized, modularized data centers. Like a 1-megawatt data center with all the power, electronics, cooling, etc., contained in the box, basically.
Colin Campbell
That’s our partner Crusoe, we love them, they’re super smart and they’re doing exactly what you’re talking about, which is: how do we drive down the cost of a data center? We mass-manufacture it.
David Roberts
Mass manufacture and distribute so it’ll be distributed just like everything else. And then you can wedge a little bit of data centering here and a little bit of data centering there rather than having to look for a mega site. But anyway, that’s probably a whole separate pod on its own. But yeah, but again, so there’s — so you could, in terms of building these sort of like off-grid, self-contained solar plus battery plus use — whoever’s in that use, that could be any manufacturing, be a factory, be anything?
Colin Campbell
Could be anyone who needs power. So data center is obviously top of the list right now. You can go set up a data center quite quickly and run it off solar and storage while you wait for your grid interconnection. If you’re planning to put a natural gas turbine, while you wait for that turbine to show up, those are actually — can be at the power levels we’re talking about, they can take a long time.
David Roberts
Yes.
Colin Campbell
So we can help sort of blaze the trail. And then there’s really a tremendous amount of utility and, like I said, symbiosis between data centers and energy storage.
David Roberts
Well, just speed too, right? Like the top — you know this — the top thing hyperscalers are saying, the top thing data centers want is speed to market. They hardly care about the cost, they just want to get hooked up, time to power. And I’m guessing, tell me if I’m wrong, but I’m guessing you can build one of these things, a solar field and a battery field attached to a manufacturing facility, faster than any large-scale centralized power plant. Is that —
Colin Campbell
That is turning out to be true.
David Roberts
How fast? Do you have a number yet? You’ve only built one.
Colin Campbell
I mean it obviously depends so much on scale, but 12 months, 18 months.
David Roberts
How long did it take to build the one you built?
Colin Campbell
I mean, the one we built from empty dirt pad to fully commissioned was like four months.
David Roberts
What?! A four-month timeline for a fully operational 24/7 power supply.
Colin Campbell
This is where the simplicity of install is so important.
David Roberts
Yeah, so again, you’re pushing away at that, the balance of system, the speed, etc. But again, already four months is just wildly faster than anything else available. Have you learned anything — I mean, this thing, this one you’ve got running has only been running for two, three months. It’s relatively new, so I’m sure there’s lots more to learn. But have you learned anything about the performance of these things in the field? Like, are you getting data that is updating any of your priors? Is anything surprising you about what’s actually happening out there?
Colin Campbell
So far, no surprises. So we’re confirming a lot of the things that we had modeled out. We have a really excellent physics-based modeling team. So I’ll give you one example. A lot of EV batteries are liquid cooled. So if you are driving around in your electric car, your cells are cooled by fluid that runs through a radiator. And we don’t use that system because of the complexity that’s associated with pumps and pipes and fluids and all of those things. And we now know for a fact that that is absolutely fine in the middle of the desert in the summer.
David Roberts
So most of the overheating probably comes from being contained in a hot car over hot pavement. In that environment, they just won’t overheat if you’re sitting them out in the open.
Colin Campbell
It’s really about the rate that we are pushing power into them.
David Roberts
Oh, I see.
Colin Campbell
So if we’re discharging, say at the fastest, over two hours, that’s pretty chill for a battery compared to showing up at a supercharger and trying to fill it in 20 minutes.
David Roberts
Again, this is out to pasture again. These are old horses that are being treated gently.
Colin Campbell
So it’s working exactly as we expected it to.
David Roberts
And you’re not worried at all that in the fullness of time, because batteries, new batteries are legendarily rapidly falling in cost, you’re not worried at all that at some point that process is going to undercut your economics. Do you think you’re going to stay ahead of that?
Colin Campbell
Yeah, well, I think a used battery is always going to be cheaper than a new one. I’m pretty confident in that. And the other piece of it is what I talked about a little bit earlier. We’re not sitting still on the non-battery parts. So we’re really, we have a great team, power electronics, mechanical engineering, software, all of that pushing down the cost of all the things that aren’t the battery.
David Roberts
Is there a future where you include other kinds of non-automotive batteries in this system? Like, is there another kind of battery that has enough juice in it to make it worth the squeeze?
Colin Campbell
I think so. I mean, we’re pretty agnostic to battery type. So it really comes down to sort of acquisition cost, in the end.
David Roberts
I’m just sort of assuming that like a toothbrush battery is just not going to be worth getting the human to walk out there and plug it in.
Colin Campbell
Let me backpedal. I don’t think ever that you’ll see like a matrix-like field of AirPods or toothbrushes.
David Roberts
So what’s the general cutoff? Like a weed whacker battery, like how big before...?
Colin Campbell
I don’t know, but I bet somewhere in the like 10 to 14 kilowatt-hour range, somewhere in there it’ll start to make sense. So maybe light hybrids, but not weed whackers.
David Roberts
And not toothbrushes. So in terms of the logistics of gathering the batteries, I’m assuming that’s all already up and running. That’s what you’ve been doing for the last few years. Is your ability to do this with the batteries going to change that side of things — how you gather them? I know there’s some sort of partnership with GM, it’s a little vague on the website, exactly what that consists of. What is that?
Colin Campbell
Well, I think we’ve really put more effort into exactly those kinds of partnerships with automakers who sometimes have the packs at their end of life and need a place to send them.
David Roberts
Do they, though? Why would they, like, why would GM end up with used GM batteries?
Colin Campbell
Well, sometimes. So some, some packs —
David Roberts
I’m so curious, what happens to a battery — like if my battery runs out, I go to a — I don’t know, a mechanic or whatever and get a new one. I have no idea what happens to it. Tell us just a little bit about what that looks like?
Colin Campbell
Everything under the sun happens to it. So if it’s a dealer, then that’s one, like, pretty consistent path. If it’s a shop, your local EV service shop, it’s actually been a challenge for them. And it’s one thing that, well before this energy storage business started, that we’ve been working hard to make as easy as possible. So we actually have sort of a — I don’t know what you want to call it, like a reverse Amazon — to make it super easy to send big batteries like this to us to figure out what they’re worth and get them on their way.
David Roberts
So they mail them to you, basically, they ship them to you.
Colin Campbell
Yes.
David Roberts
Interesting. And that — I don’t know, that just seems so expensive when I think about it. Again, so much logistics. It’s amazing how much logistics is involved in your business model.
Colin Campbell
Logistics is a real thing. It’s also remarkable how efficient it is to move mass around. Transportation costs for a battery are not a giant piece of the concern. It’s really the complexity of just like there’s a million places these end up — junkyards, people’s houses, dealerships, everything you can imagine.
David Roberts
What is the GM partnership, the newer GM partnership?
Colin Campbell
Oh, man, I honestly don’t remember.
David Roberts
The reason it caught my eye and the reason I asked about it is because I thought it would just be them getting you their old batteries. But it also says something in the press release about them maybe sending you new batteries also to be included in these power plants. So I was wondering about that — if there would ever be any reason for new batteries to wander into this milieu.
Colin Campbell
Yeah, well, maybe a couple things. GM’s been tremendously collaborative with us as we embark on the second life project. And we appreciate that. It’s very helpful to have their support as we do it. And then not specific to GM, but you do have to ask yourself the question “Why do these batteries have to be used?” And if we can do a good enough job on the balance of system costs, then they don’t. That’s not our focus right now, but it’s something that definitely is on my mind.
David Roberts
Interesting. So theoretically, you could end up being just a very competitive grid storage company that is agnostic to the source of batteries?
Colin Campbell
Could be.
David Roberts
Someday, maybe.
Colin Campbell
The thing that we’re getting good at right now, and it’s still — it’s still early days, I want to emphasize that for us — is being uniquely capable of integrating all of these zillion different battery types. So this, like, heterogeneity is something that we’re really good at.
David Roberts
Which raises a question I’ve had about Redwood forever. Recycling really forever. Now that you are big enough to sort of throw your weight around a little bit, you’re a big player in this market. Have you initiated any kind of talks with battery designers and manufacturers about trying to get batteries to be designed more for recyclability on the front end? And now that I think about it too, that would probably — like, the more sort of uniform they get and the easier to recycle it gets, I feel like that would also have the effect of making them easier to do this with, to integrate into these things with. Are you at all trying to influence the design of batteries on the front end?
Colin Campbell
That’s a great question. And I confronted that a little bit in my prior life where I was designing EV battery packs.
David Roberts
I think Tesla’s actually famous for designing batteries that are very not that. They’re very integrated into the car. They’re very — not particularly recyclable.
Colin Campbell
I’ll say a couple things about that. One is, when you’re doing things the way that we need to do them to make an impact in the world at industrial scale, having packs be disassembled by hand or even with automation, the sort of design for recyclability, that’s pretty expensive. And so I think the recycling processes that win are going to be something that is at least philosophically like backing up a truck full of packs and like dumping them into a machine.
David Roberts
Are you physically disassembling all the batteries now? Before you recycle them in the recycling process.
Colin Campbell
Right now I try not to. I try to send them into energy storage.
David Roberts
You hire people to do that.
Colin Campbell
But no, our processes don’t require a great deal of disassembly because every pack is different, and I think every pack is rightfully different in order to make a great car or a great truck or whatever it is, it’s hard to make those things.
David Roberts
So you think standardization is going to happen on the recycling end, not on the design end, basically?
Colin Campbell
I think so. And I think the processes for separating out all of the metals that are contained in a pack are going to work fine, regardless of how the pack was built.
David Roberts
Yeah, yeah, I need to do another pod just on the recycling stuff. By way of wrapping up, let’s look out a little bit into the future. When I brought this up online, a lot of people’s first reaction was, “Well, that seems like kind of a boutique distraction from the core business that Redwood’s in.” And the more I looked into it, I was like, “Well, there’s like two gazillion batteries on the way to recycling.” Again, we’re just at the front end of this. They’re just sort of trickling in now, I guess you’d say, in what is going to become a flood.
So you could see this growing and expanding quite a bit. I just wonder how you see this division relative to the recycling division. I mean, you sort of touched on this earlier. Do you think this will be, in the fullness of time, a comparably sized part of the business or even bigger than the recycling part?
Colin Campbell
Absolutely. There’s plenty of batteries out there in the world that are going to need to be reused. Like you — you hit on it. It’s like, what is North American EV pack production per year today? It’s 100 gigawatt-hours, 150 gigawatt-hours per year. And then the entire storage, I think, deployed last year in the US was — was half of that. So, the EV market is, for the moment, quite big compared to the storage market. They’re both growing, but —
David Roberts
EVs are growing faster. I mean, I’m assuming EVs are always going to dwarf stationary storage.
Colin Campbell
Storage is catching up. I think it’s about a quarter of the cells in the US that go into storage.
David Roberts
Really? That’s bigger than I would have guessed.
Colin Campbell
But the point is there’s plenty of used packs. We know that it’s inevitable they’re going to come back. So that’s to the like, is it a boutique distraction? No, I think it’s a real durable business. And to the question, is it a distraction? We are still quite committed to the metals business. I think that’s still so exciting and so important to bring back to North America.
David Roberts
And this does seem like, to me at least, this seems just to fit right in. Like in a sense, it’s almost like a version of recycling. You’re sort of recycling power. You’re recycling the power before you recycle the metals.
Colin Campbell
I was trying to think about how to say this.
David Roberts
But in the same way, you’re preventing new stuff from having to be made. I mean, in a sense, in both cases, you’re preventing the necessity for new stuff.
Colin Campbell
Yeah, I mean, the need for new stuff is gigantic. And so in order to fuel a complete electrification of the economy, there’s still a lot of new stuff we’re going to need, but we can in the short term blunt that a little bit and make it cheaper by extracting really every last drop of utility, whether it be energy storage capacity, whether it be the metals out of old things. And then if you fast forward 100 years, like it’ll all be circular.
David Roberts
So this is, especially in these depressing current times. These are among, among the places I go, my happy places is thinking about this 100-year time horizon and total circularity. And it’s interesting to think how this fits into that picture, basically. You can imagine a world of full circularity vis-à-vis metals, right, where we no longer are having to dig up any new metals, basically. We’ve reached a steady state. We’re perfectly recycling all the metals that come through.
Colin Campbell
You can. The thing I want to emphasize is that that also just makes economic sense. It is a cheaper way to provide nickel and lithium in addition to being sort of lower carbon and all of the other things that circularity provides.
David Roberts
Yes. Less grim labor implications, all that kind of stuff as well. But I was sort of thinking about how this fits into that. Like if you’re getting all the world’s batteries and recycling them and you’re sucking all this capacity out of them before you recycle them, you’re also like, that’s a big, potentially a big chunk of the energy storage we need. I don’t know if anybody’s tried to do this kind of math, like 20 years out or whatever, 50 years out. Like what, what sort of — like how much of the stationary storage market in the US do you think could ultimately be served by second life batteries?
This is all napkin math, of course.
Colin Campbell
It’s a good question. So today we can serve like 10, 15% of the market.
David Roberts
Really? Already with the batteries you’re receiving today?
Colin Campbell
Yeah, so we’re receiving something like 5 gigawatt-hours a year. And I think the US put 50 into service this year.
David Roberts
5 gigawatt-hours a year. And this plant you built, we should say, this off-grid plant, it’s like 63, not, it’s not even 100 megawatt-hours. So to really scale this up to start matching the input, that’s just going to be a lot of land, isn’t it? You’re not worried at all about the land?
Colin Campbell
I mean, this is like, this is a version of “Am I worried about the land use of solar?” And no, turns out you get a lot of, a lot of energy density coming from the sun. A lot of power density, sorry. And if you look at the size of — we can even look at our pilot plant in Nevada. If you look at the size of the battery compared to the size of the solar array, it’s 1/10 the size.
David Roberts
1/10?!
Colin Campbell
So, and that’s, we could do better. We could do 1/20 or 1/30 if we wanted to.
David Roberts
Ah, so you can shrink down the size of the battery thing. Can’t really shrink down the size of the solar.
Colin Campbell
Yeah, exactly. So, it’s not that big.
David Roberts
So for the off-grid applications, it would be the generation. That would be the land, the real land issue, not so much the batteries. What’s next? We pull our view out from 100 years out to say five. What’s next? What’s the next plant? Do you imagine being sort of the owner and developer of the next few of these as you kind of prove them out and show they can work?
Colin Campbell
What’s next is much bigger projects. So we have several of those lined up already in the 5 to 10 and bigger x the one we put in Nevada. So substantially bigger than our pilot site in Nevada. And so we’re really focused on executing those and delivering those.
David Roberts
And are those in Nevada?
Colin Campbell
They’re all over the country.
David Roberts
Really? I think of the vast west desert as where you find these big swaths of cheap land. Are you building — you have your eye on the east coast, the northeast, congested areas too?
Colin Campbell
We have projects — I’m sort of like doing the Rolodex in my head here — not quite everywhere in the country, but not just in the desert west, to your point.
David Roberts
Interesting. And I’m sure some of this is confidential, but for the projects in your pipeline, are they all off-grid, attached to solar in some sort of manufacturing facility, or are some of them going to be grid-connected?
Colin Campbell
Some of them will be grid connected. Like if you can imagine a place where somebody has put a utility-scale battery, we have a project like that. We have grid-connected grid arbitrage. We have behind the meter, front of the meter. We have paired with manufacturing, paired with renewables.
David Roberts
Any energy storage plays, basically.
Colin Campbell
Exactly. Same energy storage as any other kind.
David Roberts
As I think about the logistics, new things keep coming to mind. But in terms of your battery gathering, how many sites do you have where you’re gathering batteries? Because wherever you build one of these, you are establishing basically an ongoing relationship to some source of these batteries, right? A supply chain. You’re going to have to have batteries continually shipped between where they’re gathered and where you have this plant. How many of those battery gathering sites are there?
Colin Campbell
As this becomes a national project for us, we need sort of regional warehousing.
David Roberts
Is it all in the one Nevada plant at this point?
Colin Campbell
It’s not. We also have a big site that we’re developing and actually just opened our first recycling plant there in South Carolina. So that’s a strategic spot for us on the east coast, near a port, near a lot of industry. And that’s another logical place for us to inventory this stuff. But I imagine, in the fullness of time, we will put them where it makes sense to support these customers.
David Roberts
I just keep trying to wrap my head around the shift that you are about to undergo. Like right now you say you got 5 gigawatt-hours a year of batteries incoming.
Colin Campbell
Gigawatt-hours.
David Roberts
Yep, gigawatt-hours, sorry. I’m assuming that the line is going up and to the right.
Colin Campbell
Yes, it is.
David Roberts
How fast per year? Like, what’s next year? How steep is that line? I mean, I’m assuming it’s just going to get real steep relatively soon. But I don’t know if you’ve actually charted it out and plotted it out.
Colin Campbell
Yeah, it’s a little hard to predict, but we’ve seen 50% year-on-year growth at the beginning of this wave. And you can look back at the beginning of EV manufacturing in 2012 in volume. What was the ramp rate? And we’re going to see something like that.
David Roberts
Interesting. So we’re going to go from like 5, 10. Like having 100 GWh of batteries coming through is not crazy. Not out of the...
Colin Campbell
Yeah, I mean, you can almost just predict it. We’re making 100 gigawatt-hours today, so in 10 years we’ll be seeing those come back ready for second life.
David Roberts
And so then I just, at that level of volume, getting more power out of them will in no way be a small thing. I think this is what J. B. Straubel was kind of trying to get at in his big talk — this may look like a side thing today, but it’s going to be enormously important. If you’ve got 100 gigawatt-hours coming through, that’s a lot of power to just be throwing away. So it’s just going to be a lot more significant in five years.
Colin Campbell
It really will. So we are laying the groundwork for this. This team knows how to build things at scale. We have done it before. The business and the power electronics, the mechanical bits that we’re designing for energy storage, they’re all designed for mass manufacture, for simple assembly in the field. Because we know that this is coming — tens and hundreds of gigawatts.
David Roberts
Well, I love to see someone getting ahead of the puck. As I look around these days at US politics, it’s nice to see someone anticipating what’s going to happen and getting ready before it happens. Just a beautiful thing to witness.
Colin Campbell
Thank you. We’re having fun. We love finding something valuable that hasn’t been extracted and going after it. And this is just another example of it.
David Roberts
Yeah, it’s just a bunch of puzzles. I mean, all this second life stuff is just an enormous logistical puzzle to solve. And solving puzzles is fun.
Colin Campbell
We really enjoy it.
David Roberts
Colin, thanks so much for coming on and talking us through this. Really interesting. I think it’s a lot bigger of a deal than it sort of appears on the surface. So it was fun to — fun to dig in a little bit with you. Thanks for coming on.
Colin Campbell
So fun to be here. Great questions. Really enjoyed it.
David Roberts
Thank you for listening to Volts. It takes a village to make this podcast work. Shout out, especially, to my super producer, Kyle McDonald, who makes me and my guests sound smart every week. And it is all supported entirely by listeners like you. So, if you value conversations like this, please consider joining our community of paid subscribers at volts.wtf. Or, leaving a nice review, or telling a friend about Volts. Or all three. Thanks so much, and I’ll see you next time.
