Shaping the Future of Energy with Cara Libby

July 1, 2021

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Cara Libby is a Principal Technical Leader at the Electric Power Research Institute (EPRI). She joined EPRI in 2006 and has held multiple positions within the Renewable Energy Generation team. She currently leads EPRI’s Environmental Aspects of Solar Program, which broadly addresses environmental issues for large-scale solar projects. She is a subject matter expert in solar photovoltaic (PV) end-of-life management, PV field testing and reliability, and next-generation concentrating solar thermal power (CSP) technologies.

John Shegerian: This edition of the Impact Podcast is brought to you by Trajectory Energy Partners. Trajectory Energy Partners brings together landowners, electricity users, and communities to develop solar energy projects with strong, local support. For more information on how Trajectory is leading the solar revolution please visit

John: Welcome to another edition of the Impact Podcast. I’m so honored to have with us today Cara Libby. She’s the principal technical leader at the Electric Power Research Institute (EPRI). Welcome to Impact, Cara.

Cara Libby: Thank you, John. It’s a pleasure to be here.

John: And today, because of the marvels of technology, even though we’re having the conversation, like, we’re in the same room, I happened to be in Fresno, California and you’re in Virginia in the United States. Is that true?

Cara: That is true, just outside of our nation’s capital.

John: I love it. You know, Cara before we get talking about all the important work you and your colleagues are doing at the Electric Power Research Institute, I love you to share a little bit about the Cara Libby story. How you even got here, where you grew up, and how you evolved to this kind of role in making us a better country and doing the important work you’re doing at EPRI?

Cara: Thanks, John. Well, I have a background in mechanical engineering and I became very interested in pursuing renewable energy. So, I started my career at GE Global Research Center looking at hydrogen production technologies building electrolyzers in a lab. And a few years later, there was an opportunity to come to Afri and look at Solar Technologies. So, I studied various issues around different technology options, what they cost, how they perform reliability over their lifetimes. And in the past several years, I got more interested in environmental aspects of solar. So, that’s where a lot of my attention is now and particularly around end-of-life issues for solar. How do we look at decommissioning and recycling reuse opportunities and how to solar fit into circular economy.

John: That’s great. And where did you grow up, Cara?

Cara: I grew up in Northeast Ohio.

John: Wow! So, you’re right smack from the middle of the United States. Pretty much.

Cara: The heart land.

John: The heartland. So, solar panels historically have been given an interesting the Green Halo reputation of being potentially one of the savior’s of saving us lots of carbon emissions and making our economy and our grid green. Do they deserve that reputation? Are they as green as everybody thinks? You know, when we watch television and Bloomberg now everything’s going ESG Investments linear to the circular economy. Are solar panels still with all that green halo and are they the Panacea that we all think they are with regards to turning our economy to a green economy?

Cara: Well, we have it all-of-the-above strategy and so, solar is part of the equation but I wouldn’t go so far as to say it’s a Panacea.

John: Okay.

Cara: You’re right, as a renewable energy source, solar is relatively clean and green but there are of course impact that need to be considered from an environmental standpoint risks that need to be managed properly as we continue to deploy it.

John: And you know, as we both know, when you’re sitting closer to the epicenter of all the new administration but by the administration is really focusing on ESG, the Green Revolution, the linear to Circular economy strategies. And one of the things they’ve talked about is of course, reducing our carbon emissions to by 2030 to levels well, 50% below the 2005 levels. Talk a little bit about how achievable that goal is and what you’re doing in EPRI to be part of that huge huge sea of change that we’re about to go under here in the United States.

Cara: Yeah, that goal set by the Biden Administration equates to a tube gigaton reduction in the US’ annual energy-related emissions by 2030. If we look back from 2005 to 2020, we reduced energy-related emissions by 1 gigaton. So, as we look ahead, we have to accelerate from that pace of one gigaton over 15 years to one gigaton over five years. So, it’s a 3x acceleration that we’re going to need to achieve that target. And that requires economy-wide decarbonization not just the power sector. We know that the power sector is undergoing a massive shift in the way we generate and distribute electricity. We’re seeing coal plants retiring and a lot of investment in renewables were hearing utilities and states and corporations with 100% clean energy goals, renewable energy goals. And that’s all very important. Another important aspect is going to be electrification of transportation buildings and industrial processes. So, switching from gasoline in your vehicles to electric vehicles. And that’s going to require more electricity that’s clean and green.

John: Right. I know, you’re really one of the great solar panel experts on this planet. A lot of people have said that to me. So, I want to talk a little bit about solar panels. They’re on my roof of my house and I don’t know much about them, though. A lot of my friends are in the industry. I’ve invested in that industry but what I hear is this, that there’s lots of solar panels now out there. They’re still being put in. One of my friends who runs a huge solar farm in North Carolina said to me, “John, when they’re put in, they have a 30-year life span”. But the technology is improving so quickly. Moore’s Law is so truncated now that almost after five or six years, it’s actually as a huge return on investment by just pulling out. Even good solar panels that are still performing and switching them all out. And we’re not talking about 10,000 solar panels. We’re talking about millions of them. So, talk a little bit about where we are now in solar panel life in the United States and installation. And where are we going in terms of end-of-life solar panel? Are solar panels recyclable like electronics are, or do they pose different challenges that you’ve been working on in EPRI?

Cara: Sure. So, you’ve done several really good [crosstalk].

John: I know. I talk too much. Let’s break it down. First of all, solar panels, are they going to continue as you say, not be a Panacea, as I said, at the top of the show, but are they going to be part of the greening of America and the switch over to more renewable energy sources?

Cara: Absolutely. Globally, we have 800 gigawatts of solar installed and the pace continues to grow. So, they’re definitely growing to be around as you mentioned they’re designed for 25-30 year lifetime because we have installed about 95% of them in the last 10 years. We don’t know for sure, which specific product designs will or won’t last 25 to 30 years.

John: Right.

Cara: We conduct accelerated testing and have other ways to try to predict that. But of course, we don’t know for sure. There are examples of modules that are coming out of service early. Sometimes, that’s a warranty excursion. Sometimes, extreme weather damages modules, and they’re taken out of service early. We’ve also heard in Europe where a lot of the early deployment happened that there are economic repowering so plant owners are determining that new modules are more efficient and very cheap and that it is economically justified to replace the solar panels in their plans and then get more power per acreage.

John: Wow. And is that going to continue? So, you believe the trend of installation of solar panels is going to continue and the technology is going to continue to improve exponentially as we evolve?

Cara: We do see continued technology improvement. The module architecture is changing over time. We’re finding new ways to make modules thinner, use less material, and make them larger. They are driving down costs. There are also innovations around balance of systems and things like, above-ground wiring more reliable inverter technologies, and other innovations that are happening to continue improving performance in driving down cost.

John: Cara, before we talk about end-of-life issues, which I know are numerous, how about technologies? Is solar technology going to be more and more available not just on commercial properties or in farms or in-home situations and settings. But is also, is it going to start to be seen on the exterior of vehicles and other things that are available to sunlight as well?

Cara: So far, that’s been sort of a niche application. There is greater deployment of building-integrated PV in Europe, for example. We may see that spread to other locations as well as costs continue to fall. Right now, central station large-scale solar deployments are the largest portion of what’s being deployed distributed systems, or about a third of what we see being deployed on an annual basis.

John: Got it.

Cara: But [inaudible] to get the amount of solar to meet these goals, I think the fastest and cheapest way to get that is these large installations.

John: Got it. More like solar farms, the big soul. You know, and for our listeners who just joined us, we’ve got Cara Libby with us. She’s the principal technical leader in EPRI – Electric Power Research Institute. You could find Cara and her colleagues and all the important work they’re doing it. Cara, now, let’s switch to the important topic of end of life. When solar panels, like you said, whether because of damage or other challenges, whether challenges when the solar panels come to their end of life, why are they a challenge to recycle as opposed to potentially other middle-of-the-road electronics, like a television or cell phone?

Cara: It’s really the way they are constructed. That makes them difficult to take apart. Manufacturers design them to last 25 to 30 years outside in the elements. And so, the typical construction is a top layer of glass and then you have a polymer encapsulant that attaches that glass to the semiconductor material. It does the solar light to electricity conversion. And then on the backside, you have another layer of polymer. And the whole thing is surrounded by an aluminum frame and there’s additional polymer glue that holds that together to prevent moisture from coming into the module and lead to corrosion. So, they’re packaged such that they are not going to come apart easily. And when we look at recycling processes, they usually involve crushing and grinding and sometimes thermal and other chemical processes to try to separate out all these materials that have been essentially pulling together.

John: So, the glue makes it really hard to recycle, huh?

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Cara: It does.

John: So, are you saying, at this point in the technology that exists, it’s not cost-effective to recycle solar panels because of the tediousness of removing the glue and trying to extract the potentially valuable materials that’s encapsulated in solar panels?

Cara: I think it’s important to compare recycling costs to the alternative. And today, most land, most modules are solar panels are being sent to landfills. There in most jurisdictions at least in the US, are not any restrictions on doing so. And to landfill, a solar panel is less than $2 per panel. Whereas recycling, we hear anecdotally from every members who are having to recycle modules but it costs between 10 and 30 dollars per module to recycle. So, in many cases, it’s an order of magnitude higher cost to show that environmental stewardship and choose recycling over landfilling.

John: Good point. So, what happens? We know landfill is a linear economy model and that if materials are landfill, the solar panel’s landfill or solar farm is landfilled, those materials have no chance of recovery. And potentially, they could be also some hazardous materials that leach into the ecosystem ground and water supply, vegetation animals, and eventually humans as well. So, the net negatives that come with that even though it’s, as you say the cheaper option, Cara. What about though, if you were to recycle these at the cost that you talk about ten to thirty dollars a panel, what can be extracted that what that’s valuables or any offset that you get on those on those then costs, or is that the net cost after you’ve already offset the valuable materials that you can extract from them?

Cara: Right. So, today’s recycling technologies are largely not optimized for PV are for solar panels. We are largely using existing glass recycling lines to process solar panels and about 80% of materials can be recovered. And that’s largely the bulk materials like glass aluminum and some copper. The more valuable materials like silicon and silver are oftentimes not being recovered. And so, we really need improvements in these recycling technologies to recover more of that valuable material, that could help offset recycling costs.

John: Do you work with both manufacturers and recyclers on trying to come up with solutions in bridging the gaps on how to make these more.. for lack of better terms, to make the technology on the manufacturing side greener and make them more recyclable and to work with recyclers on perfecting their technology so they can recycle these panels better?

Cara: There is a lot of activity happening to improve both the design. I mean, you really have to start with the beginning, with the end in mind. So, I think it’s about that [inaudible].

John: You’re right.

Cara: [inaudible] need to be designed so that they can be more easily managed to end of life in a way that’s cost-effective. And some manufacturers are showing leadership and making their products more sustainable. We know that First Solar offers recycling for their products. They consider whether a new product design is recyclable when they prepare to launch that new product. Others, like SunPower, have achieved certain designation certifications that mean that their materials of construction are more sustainable and that the modules will be recycled at end of life and other manufacturers are taking similar actions.

John: So, that means that they come to you for advice or for guidance on how to make their products both greener and more recyclable, which really means the same thing, but they want to manufacture them greener which in essence and maybe construct them in a better more logical way so they’re more recyclable when they come to their end of life.

Cara: They’re largely responding to procurement decisions and requirements. So, increasingly, the companies that are building and owning solar power plants are requiring those new technologies. Say, don’t contain lead or are built with materials that are sustainably sourced with packaging in mind. So, we do see this shift as the requirements for a more circular economy type. Product designs are required is driving changes in how those products are manufactured.

John: And I’m on your website now. It’s full of great information for our listeners and viewers are just joining us. We’ve got Cara Libby with us today. She’s the principal technical leader in EPRI. You could find them in Is EPRI leading the way on responsible solar recycling?

Cara: We’re one of the organizations that’s trying to drive research in this area. Some of the needs are immediate. So, as solar panels break during shipment, during installation, during maintenance, maybe a weed wacker knocks a stone into a solar module, plant owners are having to handle these end-of-life materials. And we are trying to help them understand what their end-of-life management options are, how to navigate the recycling space, and provide information and tools for them to make decisions.

John: That’s great. So, are you hopeful, Cara with all the great work you’ve been doing already for 15 years at EPRI and your colleagues are doing, that by the time lots of these panels start peeling out and need to be responsibly recycled that the technologies by the recyclers will have been developed to handle them and keep them out of landfills, you hopeful that word nearing that point?

Cara: I am hopeful. When we started this work a few years ago, almost all of the recycling was happening in Europe. And since that time, we’ve seen a dedicated recycling facility be established in France and others are under development. In the U.S., we’ve identified 25 recyclers that are now publicly saying that they accept solar modules and that number continues to rise. So, while there is an immediate concern, there’s also some time, as I mentioned, most of the solar that has been built still has 10-15 years of useful life before we have to worry about recycling. And so, I do think and I am optimistic that over the next decade or two, we’re going to get there and drive down recycling costs.

John: Um, I know on your homepage is a great YouTube video that I watched while examining the pace of US carbon reduction based on 2030 goals. And then, you also have a lot of solar information at And for our listeners and viewers out there, there’s a lot more to learn when you go to the website. Cara, what else are you working on at EPRI besides solar? I know that sounds like it’s so specific but what else has EPRI covered in terms of energy technologies and things of that such?

Cara: We have three sectors addressing generation which include our renewables work, nuclear power, and also power delivery and utilization. And so, energy efficiency continues to be a big focus across our work. We’re looking at ways to more efficiently produce, deliver, and use electricity. And we are adding a focus on advanced energy carriers. So, things like hydrogen and ammonia, and biofuels that can help with this transition to greater renewable energy.

John: Do you foresee a time when manufacturers are able to make viable and technologically efficient solar panels without glue?

Cara: I do have some ideas. There are some efforts out there to vacuum seal modules. I think we’ll have to wait and see but I have faith that there are good innovators out there and that we will come up with solutions to these challenges.

John: What’s the vote most for our laymen out there that are so interested in really learning today about solar panels more. What’s the most valuable materials that when recycled responsibly, even at a higher cost, recyclers are able to pull out of solar panels?

Cara: Well, today they’re pulling out the aluminum so that has an obvious..

John: Right.

Cara: ..recycling opportunity. Glass, if we could recover glass in higher purity, could have greater opportunity for resale into higher-value markets. I talked to one recycler recently, who has developed a niche product where they create spherical glass that is applied on roadway paint to make it more reflective.

John: Wow.

Cara: So, I thought that was pretty innovative. I think we’ll continue to see new uses for the material that’s being recovered from solar modules. The silicon is really the other opportunity. Today, when we recover silicon, it’s usually low-grade silicon and if we can get it up to solar grade, that would allow it to be reused in manufacturing new modules, new solar panels.

John: Cara, the show’s all about you and all the important work you and your colleagues are doing at EPRI. Do you have any final words for our listeners or viewers today who want.. We have a young audience and they’ll listen to you and they might want to be the next Cara Libby. Do you have any advice for our students or our young entrepreneurs out there that not only want to have a nice and interesting job but also want to have a job that makes the world a better place like you do and your colleagues do as well?

Cara: There’s a lot of opportunity within the renewable energy space. I certainly would encourage young people to get involved in solar power. I think, there’s a lot of great opportunities around this end-of-life space but also things like Land Management. We’re looking at really cool stuff like growing crops under solar arrays and livestock to graze. So, lots of really innovative solutions as we look toward deploying this technology more broadly.

John: Well, she’s Cara Libby. Cara, you’re always welcome back on the Impact Podcast. For our listeners and viewers to find Cara, her colleagues, and all the great people at EPRI that are making the world a better place, please go to Cara Libby, you’re making a great impact. You are making the world a better place. I thank you for your time today. You’re always welcome back on our show. Share your continued journey in making the world a greener and better place.

Cara: Thank you so much, John. It’s been an honor.

John: This edition of the Impact Podcast is brought to you by the Marketing Masters. The Marketing Masters is a boutique marketing agency offering website development and digital marketing services to small and medium businesses across America. For more information on how they can help you grow your business online, please visit