How to boost the sustainability of solar cells

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Hello, and welcome to the Physics World Weekly

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podcast. I'm Hamish Johnston.

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In this episode,

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I'm exploring how we can improve the sustainability

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of solar cells

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with 4 researchers

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at the UK's

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University of Oxford.

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They've coauthored

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the roadmap on established

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and emerging

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photovoltaics

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for sustainable

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energy conversion.

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First though, we'd like to thank Pfeiffer Vacuum

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and Fab Solutions

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for supporting this podcast.

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Pfeiffer is part of the Busch Group, one

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of the world's largest

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manufacturers

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of vacuum pumps, vacuum systems, blowers,

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compressors,

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and gas abatement systems.

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Under its umbrella,

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the group houses 3 well known brands, Busch

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vacuum solutions,

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Pfeiffer,

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and Centrotherm

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clean solutions.

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The sustainable production of solar cells is a

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significant step towards clean energy generation.

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Vacuum technology plays a crucial role in the

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development and production of solar cells,

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including coating,

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laminating,

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and other key production steps.

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The use of vacuum technology

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ensures that coating materials are evenly distributed

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free of air bubbles and have a uniform

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thickness.

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This significantly

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increases

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the efficiency

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of each solar cell.

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Through intensive

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research and development

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in collaboration with its customers,

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Pfeiffer has developed

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tailored vacuum solutions

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for solar cell production.

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They enable faster production processes,

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higher efficiency,

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and a longer lifespan

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of the solar modules.

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Find out more at pfeifferdashvacuum.com.

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In 2020,

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the UK's Henry Royce Institute

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teamed up with the Institute of Physics and

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the Institute For Manufacturing

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to release a series of roadmaps

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that focused on the roles that materials will

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play in the UK's transition to clean and

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sustainable

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sources of energy.

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One roadmap charted the future of materials

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for photovoltaics,

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also known as solar cells, and it received

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lots of positive feedback from the photovoltaic

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community.

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Today,

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4 years on,

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86

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photovoltaic

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experts from around the world have joined forces

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to update and expand on that success.

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To produce the blockbuster

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roadmap on established and emerging photovoltaics

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for sustainable

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energy conversion.

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And that's published in the Journal of Physics

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Energy.

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I'm at the University of Oxford to talk

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with 4 of those experts.

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They are the inorganic

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chemist,

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Robert Hoy,

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the physicists,

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Nikita Noel

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and Pascal

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Kuyenberg,

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and the materials scientist,

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Sebastian Bonilla.

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Hi

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everyone. Welcome to the podcast.

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Hello. Hello.

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So Robert, the first question is for you.

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Can you explain what sustainability

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means in terms of photovoltaic

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production

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and use? Sure. So by sustainability,

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the main thing we mean is, how the

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electricity is produced. So for a solar cell,

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it harvests sunlight or harvests any form of

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lighting, produces,

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green electricity without producing any greenhouse gases.

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So and also right now, photovoltaic's,

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you know, very cheap compared to other sources

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of energy,

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and,

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in many parts of the world, they're the

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cheapest source of green electricity.

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And you can use that for, you know,

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powering homes, for

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recharging electric vehicles.

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So that's one, you know, one way in

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which we mean sustainability.

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But also we're thinking about the life cycle

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of a solar cell. We're thinking about how

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they're produced

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and how they're used and what happens to

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them at the end of life.

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So in terms of production, we're thinking about

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what sort of elements go into these solar

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cells, and we're thinking about how can we

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make solar cells such that we're not make

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we're not relying on expensive or scarce elements.

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And we're also thinking about, what the materials

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are that are going into these solar cells.

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Do you want to avoid any materials that

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could harm the environment by deploying these technologies?

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And we're also thinking about what the CO2

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footprint is.

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And right now that's quite low. So the,

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you know, CO2 payback time for silicon solar

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cells is quite very short, about 3 years.

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And for some thin film based technologies, which

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have a much lower CO2 footprint, the payback

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time for that is, you know, even less

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than a year. So these are very sustainable

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technologies right now. And of course at the

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end at the end of the life, we're

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thinking about what happens to these once they're,

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they finish their useful life lifespan.

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And currently, it's the the cheapest way the

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cheapest thing to do right now is just

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to,

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throw away a silicon solar cell and to

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buy a new one.

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But we're thinking about, you know, other ways

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to,

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recycle

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and reuse some of these scarce elements which

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are being utilized in solar cells. So that's

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what we're thinking about with sustainability.

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So Sebastian, much of your research focuses on

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silicon solar cells

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which currently dominate the market.

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What are the sustainability

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challenges that are specific to silicon and how

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can they be overcome?

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So, when we talk about silicon solar modules,

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we have 2 big things that, that that

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sort of are interconnected.

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The first one, Robert already touched a little

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bit on which is to do with the

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raw materials that are used to make solar

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panels.

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So

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the,

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the context to all of this is that

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making silicon solar modules is extremely, extremely cheap.

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I mean, a solar module today sells for

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less than 10¢,

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of US dollar per watt, which is one

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of the lowest,

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sources of electricity everywhere.

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So the,

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the forecast to this is simply that we're

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going to continue to make much more silicon

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solar modules and install them everywhere.

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When we get to making billions of solar

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modules per year,

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we're talking about

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so such a large area that the materials

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that we use to make those solar modules

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start to become very constrained.

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So, we we we have issues with some

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of the materials that we use. For example,

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we use a lot of silver and if

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we continue to expand these manufacturing of solar

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modules then we're going to essentially use almost

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the whole of the silver supply in the

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world, which essentially we cannot do.

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We also use bismuth for soldering, we use

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indium for transparent conductors.

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So those materials really are some of the

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keys that we need to that we need

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to address

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in the future.

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Now that's the big problem, let's say.

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Then in terms of the one second problem

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a little bit smaller has to do with

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recycling and circularity.

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So there have been loads of reports

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sort of stating how difficult it's going to

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be to recycle solar modules,

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But the reality of it is that it's

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not as difficult as people as people tend

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to think. A solar module is around 80

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to 90% glass

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and then maybe 10%

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aluminum

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and then another 10% of plastic and the

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silicon solar cell

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itself. So in in terms of the silicon

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that goes into it, it's not a huge

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amount. Glass, we know how to recycle. Aluminum,

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we know how to recycle. So we know

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that there is going to be a big

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sort of waste stream of solar panels coming

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out in the next 10 to 20 years.

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But we're I think we're well prepared to

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to deal with that. So so I would

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say the the really big problem for scalability

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is is material,

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use.

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I see. And I'm guessing that because silicon

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is such a ubiquitous

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material,

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that

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the the the challenges that we face with

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silicon solar cells are similar to computer chips

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and and other

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silicon based technologies. Or are there specific challenges

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associated with silicon solar cells?

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So it's a little bit different than semiconductor

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the the microchip semiconductors

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in in the sense that

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making a silicon solar cell is far easier

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than making a microchip.

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So a big part of the cost of

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making a Silicon solar cell is just the

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price of Silicon,

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right? So extracting and processing Silicon is a

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very energy intensive process and so this,

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this costs quite a bit of money. Whereas

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when you're making a microchip,

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you essentially take a very big lump of

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silicon

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and then you pass it through around

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100 of different processes and what you end

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up at the end is is an extremely

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expensive,

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microchip.

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Right? And and so in in that sense,

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they're they're slightly different. For silicon solar cells,

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we think a lot about where the material

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comes from, what is the energy that is

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being used to make it into into a

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solar cell. Whereas for microchips, we primarily think

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about,

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can we make all of those really complicated

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processes,

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in a in a scalable way and in

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different parts of the world so that we

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can have a sustainable or safe,

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supply chain for microchips. So that's that's different

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in a sense. Yeah. So Nikita, your expertise

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lies in the development of photovoltaics

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based on perovskite

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materials.

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And you'd be happy to know that at

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the Institute of Physics Publishing, where where I

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work, we have a a meeting room called

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perovskite.

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So so what are perovskites,

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Nikkita? And how are they being used to

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develop more sustainable devices?

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So one of the things with perovskites that's

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actually really interesting is that I feel like

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in order to not make,

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you know, quantum materials people really upset, we

283
00:10:10,065 --> 00:10:11,024
need to talk about what specifically which type

284
00:10:11,024 --> 00:10:12,009
of perovskite we're talking about here. So type

285
00:10:12,009 --> 00:10:13,183
of perovskite we're talking about here. So perovskite

286
00:10:13,183 --> 00:10:14,985
is basically just a crystal structure. So anything

287
00:10:14,985 --> 00:10:17,129
that crystallizes in an ABX 3 crystal structure

288
00:10:17,129 --> 00:10:19,389
can be called a perovskite.

289
00:10:25,044 --> 00:10:26,725
And one of the fun facts that we

290
00:10:26,725 --> 00:10:28,964
like to bandy around is that it is

291
00:10:28,964 --> 00:10:31,284
actually the structure of the most common mineral

292
00:10:31,284 --> 00:10:32,985
on Earth, which is bridgemanite.

293
00:10:34,084 --> 00:10:34,584
But

294
00:10:34,964 --> 00:10:36,584
when we're talking about photovoltaics,

295
00:10:37,044 --> 00:10:39,445
we're talking about an entirely man made class

296
00:10:39,445 --> 00:10:39,990
of perovskites,

297
00:10:41,190 --> 00:10:43,129
specifically the lead halide perovskites.

298
00:10:43,589 --> 00:10:45,589
So if we're thinking about this ABX 3

299
00:10:45,589 --> 00:10:47,909
crystal structure on the a sites, we can

300
00:10:47,909 --> 00:10:48,409
put

301
00:10:48,870 --> 00:10:51,990
small organic cations. We can put inorganic cations

302
00:10:51,990 --> 00:10:52,730
like cesium.

303
00:10:53,274 --> 00:10:56,075
And for PV applications, we're usually talking about

304
00:10:56,075 --> 00:10:58,075
lead or tin on the B site and

305
00:10:58,075 --> 00:10:59,934
on the X site we have halides.

306
00:11:01,754 --> 00:11:04,475
So in terms of how these materials are

307
00:11:04,475 --> 00:11:07,615
being used in terms of sustainable photovoltaics,

308
00:11:08,819 --> 00:11:11,059
like Robert mentioned before, there are a 1000000

309
00:11:11,059 --> 00:11:12,839
different definitions of sustainability.

310
00:11:13,860 --> 00:11:16,259
And if we think about the elements that

311
00:11:16,259 --> 00:11:17,639
we're putting into perovskites,

312
00:11:18,339 --> 00:11:20,325
all of these are earth abundant elements.

313
00:11:21,365 --> 00:11:24,325
So just by virtue of that, we, we

314
00:11:24,325 --> 00:11:26,665
don't have a problem on that front.

315
00:11:27,445 --> 00:11:30,325
There are potential issues that may crop up

316
00:11:30,325 --> 00:11:32,024
with CGM, for example.

317
00:11:32,965 --> 00:11:34,940
But one of the things that people like

318
00:11:34,940 --> 00:11:36,799
to talk about here is that, well, actually

319
00:11:37,179 --> 00:11:39,039
we don't have that much cesium.

320
00:11:39,419 --> 00:11:40,940
It's not that we don't have that much

321
00:11:40,940 --> 00:11:43,100
cesium. We don't mind a lot of cesium

322
00:11:43,100 --> 00:11:43,839
at the moment.

323
00:11:44,220 --> 00:11:45,820
And when we think about these things, we

324
00:11:45,820 --> 00:11:47,934
have to think about supply and demand. The

325
00:11:47,934 --> 00:11:49,375
reason why we don't mind a lot of

326
00:11:49,375 --> 00:11:51,615
it is because there isn't a big demand

327
00:11:51,615 --> 00:11:53,934
for it at the moment. If parasites were

328
00:11:53,934 --> 00:11:55,934
to become a thing, there might be a

329
00:11:55,934 --> 00:11:57,695
big demand for it on the market. And

330
00:11:57,695 --> 00:11:59,615
then we don't necessarily have to deal with

331
00:11:59,615 --> 00:12:00,274
our problem

332
00:12:00,740 --> 00:12:02,839
with regards to lead. I know

333
00:12:03,299 --> 00:12:05,139
a lot of people might, you know, have

334
00:12:05,139 --> 00:12:07,320
their hackles raised a little bit about this,

335
00:12:07,379 --> 00:12:08,200
but really

336
00:12:08,579 --> 00:12:10,820
the fraction of lead that we use, because

337
00:12:10,820 --> 00:12:12,360
this is a thin film technology,

338
00:12:12,740 --> 00:12:15,220
the amount of lead that actually goes into

339
00:12:15,220 --> 00:12:17,245
that absorbing layer is minuscule.

340
00:12:18,184 --> 00:12:20,345
And there is a lot of research being

341
00:12:20,345 --> 00:12:22,445
done in terms of how we actually

342
00:12:23,065 --> 00:12:26,184
deal with potential lead leakage issues and what

343
00:12:26,184 --> 00:12:27,325
the bioavailability

344
00:12:27,865 --> 00:12:30,820
of that lead would be if a panel

345
00:12:30,820 --> 00:12:32,360
were to break, for example.

346
00:12:33,220 --> 00:12:34,679
And if you think about

347
00:12:35,460 --> 00:12:37,799
really how much carbon is generated

348
00:12:38,580 --> 00:12:41,059
in producing these things, if we compare it

349
00:12:41,059 --> 00:12:42,919
to something like Silicon, for example,

350
00:12:43,325 --> 00:12:45,565
originally, when you're making a silicon solar panel,

351
00:12:45,565 --> 00:12:46,304
and Sebastian

352
00:12:46,924 --> 00:12:47,904
mentioned this earlier,

353
00:12:48,764 --> 00:12:51,184
you do have a lot of carbon emissions

354
00:12:51,245 --> 00:12:54,625
generated there and of course that payback time

355
00:12:54,684 --> 00:12:57,710
is still fairly low. With perovskites it's even

356
00:12:57,710 --> 00:12:59,870
lower. And one of the beauties of this

357
00:12:59,870 --> 00:13:02,909
particular material is that you don't just have

358
00:13:02,909 --> 00:13:05,409
to have, let's say a single junction perovskite

359
00:13:05,629 --> 00:13:07,870
solar cell because of the fact that it's

360
00:13:07,870 --> 00:13:09,570
actually really easy to process.

361
00:13:09,934 --> 00:13:12,815
What perovskites can very readily do is hold

362
00:13:12,815 --> 00:13:14,115
hands with other technologies.

363
00:13:14,735 --> 00:13:17,475
And for example, have a perovskite silicone tandem

364
00:13:17,934 --> 00:13:20,654
where these either of these technologies might be

365
00:13:20,654 --> 00:13:23,955
around 26, 25% on their own, but together

366
00:13:24,174 --> 00:13:25,394
currently over 34%.

367
00:13:25,960 --> 00:13:27,720
Percent. So again, when you start thinking about

368
00:13:27,720 --> 00:13:29,340
things like that, how much,

369
00:13:30,600 --> 00:13:32,679
let's say what degree of carbon emissions you

370
00:13:32,679 --> 00:13:34,700
have in order to make these devices.

371
00:13:35,320 --> 00:13:37,659
When you start thinking about things like even

372
00:13:37,855 --> 00:13:40,995
junction perovskites or perovskites, silicon tandems, for example,

373
00:13:41,294 --> 00:13:44,035
you have a lot less carbon output

374
00:13:44,654 --> 00:13:46,414
per the amount of power that you have

375
00:13:46,414 --> 00:13:46,914
generated.

376
00:13:47,375 --> 00:13:50,595
So in terms of perovskites being a sustainable

377
00:13:50,735 --> 00:13:53,215
option for PV, I think we're in a

378
00:13:53,215 --> 00:13:56,040
good spot. Okay. And and what about efficiency?

379
00:13:57,700 --> 00:14:00,420
Is the reason you're interested in perovskites because

380
00:14:00,420 --> 00:14:02,740
they they have the potential or perhaps they

381
00:14:02,740 --> 00:14:06,440
are already more efficient than silicon solar cells?

382
00:14:07,024 --> 00:14:08,705
So I would say on a lab scale

383
00:14:08,865 --> 00:14:10,144
and this is one of the things that

384
00:14:10,144 --> 00:14:11,924
makes perovskites really exciting.

385
00:14:12,225 --> 00:14:14,465
So I started working on this material during

386
00:14:14,465 --> 00:14:15,125
my PhD,

387
00:14:15,665 --> 00:14:19,024
and our first ever devices were somewhere around

388
00:14:19,024 --> 00:14:19,524
6%.

389
00:14:20,065 --> 00:14:22,720
And then literature was at 3% power conversion

390
00:14:22,720 --> 00:14:24,100
efficiency, which is effectively,

391
00:14:25,279 --> 00:14:27,700
how well you actually can convert,

392
00:14:28,240 --> 00:14:29,940
light into electricity.

393
00:14:30,559 --> 00:14:32,500
And right now, we're over 26%

394
00:14:32,879 --> 00:14:33,940
on a lab scale.

395
00:14:34,320 --> 00:14:36,735
And like I said before, if we start

396
00:14:36,735 --> 00:14:38,995
thinking about perovskite silicon tandems,

397
00:14:39,455 --> 00:14:40,355
we have

398
00:14:40,654 --> 00:14:43,075
exceeded the efficiency that either of these technologies

399
00:14:43,134 --> 00:14:45,134
can get to, but on their own. So

400
00:14:45,134 --> 00:14:48,274
it really is incredibly promising to have this

401
00:14:48,899 --> 00:14:51,539
material or this class of materials that can

402
00:14:51,539 --> 00:14:52,279
not only

403
00:14:52,659 --> 00:14:54,839
provide high efficiency devices,

404
00:14:55,220 --> 00:14:58,579
but provide power in a sustainable way. I

405
00:14:58,579 --> 00:14:59,079
see.

406
00:14:59,539 --> 00:15:02,980
So, Pascal, your research focuses on creating solar

407
00:15:02,980 --> 00:15:04,440
cells using organic

408
00:15:04,794 --> 00:15:05,294
semiconductors.

409
00:15:06,075 --> 00:15:08,174
Can you give some examples of the materials

410
00:15:08,235 --> 00:15:10,315
that you work with and how they could

411
00:15:10,315 --> 00:15:12,095
be used to create sustainable

412
00:15:12,794 --> 00:15:13,615
solar cells?

413
00:15:13,995 --> 00:15:15,455
Sure. So semiconductors,

414
00:15:15,995 --> 00:15:17,455
so we are working with organic

415
00:15:18,459 --> 00:15:21,179
perovskites are semiconductors, silicon is a semiconductor. So

416
00:15:21,179 --> 00:15:23,339
you do need a semiconductor to make a

417
00:15:23,339 --> 00:15:26,159
solar cell. The organic, inorganic semiconductor

418
00:15:26,539 --> 00:15:28,779
stems from is is is a reference to

419
00:15:28,779 --> 00:15:30,879
organic chemistry. So we work with molecules

420
00:15:31,259 --> 00:15:33,995
based on carbon and hydrogen with some heteroatoms

421
00:15:34,455 --> 00:15:35,115
in them.

422
00:15:36,774 --> 00:15:37,674
Broadly speaking,

423
00:15:38,134 --> 00:15:40,634
these organic semiconductors come in 2 flavours,

424
00:15:41,415 --> 00:15:43,035
that are related to a processing

425
00:15:43,654 --> 00:15:44,154
technology.

426
00:15:44,535 --> 00:15:45,179
So there's

427
00:15:45,580 --> 00:15:48,779
solution processing, wet chemistry printing, and that uses,

428
00:15:49,019 --> 00:15:51,419
polymers and then a a something called small

429
00:15:51,419 --> 00:15:53,039
molecules, and then there's,

430
00:15:53,419 --> 00:15:55,759
physical vapor deposition, so evaporating,

431
00:15:56,860 --> 00:15:59,279
molecules that are in tendency a bit smaller.

432
00:16:00,154 --> 00:16:02,714
But they're still both organic semiconductors. And one

433
00:16:02,714 --> 00:16:05,834
example where such organic some semiconductors are already

434
00:16:05,834 --> 00:16:08,554
used in our everyday life is the displays

435
00:16:08,554 --> 00:16:10,554
in our smartphones and now more and more

436
00:16:10,554 --> 00:16:12,394
in TVs as well. So we work with

437
00:16:12,394 --> 00:16:13,695
this class of material.

438
00:16:14,440 --> 00:16:14,940
And

439
00:16:16,040 --> 00:16:17,639
then what they they have they're a bit

440
00:16:17,639 --> 00:16:19,340
different from the, inorganic

441
00:16:19,800 --> 00:16:22,600
semiconductors that we've heard about so far in

442
00:16:22,600 --> 00:16:25,639
that, you can make them spectrally selective. So

443
00:16:25,639 --> 00:16:26,294
you can

444
00:16:26,615 --> 00:16:28,714
only absorb a certain part of the light.

445
00:16:28,855 --> 00:16:31,894
That opens up a new application, the semi

446
00:16:31,894 --> 00:16:33,434
transparency and color selectivity.

447
00:16:33,894 --> 00:16:35,894
One thing people are thinking about at the

448
00:16:35,894 --> 00:16:39,679
moment, for example, is, the combination of agricultural

449
00:16:40,620 --> 00:16:43,740
products. So integrate them into greenhouses, only absorb

450
00:16:43,740 --> 00:16:46,799
light that plants don't use. There's further applications

451
00:16:46,940 --> 00:16:47,679
like indoor,

452
00:16:48,139 --> 00:16:51,340
harvesting the indoor light to power the sensors

453
00:16:51,340 --> 00:16:53,519
and transmitters for the Internet of Things.

454
00:16:53,980 --> 00:16:54,480
And

455
00:16:59,095 --> 00:17:01,434
And, we're talking a lot about sustainability

456
00:17:02,214 --> 00:17:02,954
here as well.

457
00:17:04,454 --> 00:17:04,954
Generally,

458
00:17:06,375 --> 00:17:09,275
it's organic photovoltaics that have a great

459
00:17:09,960 --> 00:17:12,140
footprint for. In terms of

460
00:17:12,519 --> 00:17:13,019
sustainability,

461
00:17:14,200 --> 00:17:16,359
it's very low embedded energy, that means low

462
00:17:16,359 --> 00:17:17,259
embedded carbon.

463
00:17:19,319 --> 00:17:21,980
It doesn't use any heavy metal, no scarce

464
00:17:22,359 --> 00:17:22,859
elements.

465
00:17:23,305 --> 00:17:24,365
So that's all great.

466
00:17:24,984 --> 00:17:27,164
At the moment, it's made from petrochemicals.

467
00:17:28,184 --> 00:17:29,404
And as the petrochemical

468
00:17:29,705 --> 00:17:30,205
industry

469
00:17:30,585 --> 00:17:31,085
decarbonizes,

470
00:17:31,945 --> 00:17:35,005
that, the organic solar cells will also decarbonize.

471
00:17:35,144 --> 00:17:37,325
In principle, you can make this from renewable

472
00:17:37,545 --> 00:17:38,045
feedstock.

473
00:17:39,289 --> 00:17:41,369
And maybe organic solar cells are actually a

474
00:17:41,369 --> 00:17:44,410
good target, first target for this, this renewable

475
00:17:44,410 --> 00:17:46,429
feedstocks of of, petrochemicals

476
00:17:46,730 --> 00:17:48,349
as it is a high value product.

477
00:17:48,970 --> 00:17:50,109
And and what about

478
00:17:50,904 --> 00:17:52,664
robustness? Because, you know, when I think about

479
00:17:52,664 --> 00:17:53,164
semiconductors

480
00:17:53,704 --> 00:17:56,845
well, a semiconductor like silicon or a perovskite,

481
00:17:57,065 --> 00:17:58,984
that's like a a rock, isn't it? You

482
00:17:58,984 --> 00:18:01,545
could you could imagine that lasting forever. But

483
00:18:01,545 --> 00:18:02,285
an organic

484
00:18:02,904 --> 00:18:03,404
material,

485
00:18:03,865 --> 00:18:05,785
does it have a shorter lifetime? Or is

486
00:18:05,785 --> 00:18:07,750
it you have to be more precious with

487
00:18:07,750 --> 00:18:10,390
it, protecting it from air or those sorts

488
00:18:10,390 --> 00:18:13,109
of things? Right. So stability is is, an

489
00:18:13,109 --> 00:18:16,490
important point for all all organ for all,

490
00:18:17,269 --> 00:18:19,910
solar technologies, and it is certainly for organic

491
00:18:19,910 --> 00:18:20,890
PV as well.

492
00:18:21,515 --> 00:18:23,434
You intend to compare to silicon, which is

493
00:18:23,434 --> 00:18:25,994
indeed a quite robust material. You have to,

494
00:18:26,315 --> 00:18:28,634
do a better job at encapsulating it, so

495
00:18:28,634 --> 00:18:31,034
it's shielding it from from oxygen and and

496
00:18:31,034 --> 00:18:31,534
moisture.

497
00:18:31,835 --> 00:18:32,474
But then,

498
00:18:33,115 --> 00:18:34,974
companies have now the the certificates,

499
00:18:35,710 --> 00:18:37,330
for the Skorp, the IEC

500
00:18:38,670 --> 00:18:39,170
62115.

501
00:18:41,549 --> 00:18:43,549
And that one certifies sort of sort of

502
00:18:43,549 --> 00:18:46,049
the the industry standard for for stability.

503
00:18:46,910 --> 00:18:48,210
I see. Okay.

504
00:18:48,944 --> 00:18:51,585
So Robert, we're we're back to you. And,

505
00:18:51,904 --> 00:18:54,804
you've coauthored a section of the road map

506
00:18:54,944 --> 00:18:56,325
that looks at indoor

507
00:18:56,865 --> 00:18:57,365
photovoltaics.

508
00:18:58,144 --> 00:19:01,125
That's, something that Pascal's mentioned Yeah. Already.

509
00:19:02,029 --> 00:19:04,669
What role will these play in creating a

510
00:19:04,669 --> 00:19:07,150
sustainable future? I suppose what is an indoor

511
00:19:07,150 --> 00:19:07,650
photovoltaic?

512
00:19:08,029 --> 00:19:09,710
Sure. Maybe I'll I'll start by saying, you

513
00:19:09,710 --> 00:19:11,150
know, one of the really great things about

514
00:19:11,150 --> 00:19:13,630
photovoltaics is a whole wide range of things

515
00:19:13,630 --> 00:19:15,329
you can use them for. I mean,

516
00:19:15,644 --> 00:19:17,404
for most of us, we mostly just think

517
00:19:17,404 --> 00:19:20,205
about using solar cells on rooftops, on solar

518
00:19:20,205 --> 00:19:22,285
farms. And, you know, that's certainly the biggest

519
00:19:22,285 --> 00:19:25,085
market. That's certainly the most common reason we

520
00:19:25,085 --> 00:19:27,644
use solar cells, but there's wide range of

521
00:19:27,644 --> 00:19:28,845
other things you can do with them. You

522
00:19:28,845 --> 00:19:30,720
can integrate them to buildings to make more

523
00:19:30,880 --> 00:19:33,519
sustainable building buildings. You can integrate them with,

524
00:19:33,839 --> 00:19:35,059
satellites or cars.

525
00:19:35,679 --> 00:19:37,919
But you can also use them indoors. So

526
00:19:37,919 --> 00:19:40,819
an indoor follow-upotake is just any follow-upotake device

527
00:19:41,039 --> 00:19:42,900
used indoors under indoor illumination.

528
00:19:43,875 --> 00:19:46,115
The reason why this has become so interesting

529
00:19:46,115 --> 00:19:48,055
for a lot of people now is because

530
00:19:48,275 --> 00:19:50,275
of the increasing importance of the Internet of

531
00:19:50,275 --> 00:19:52,855
Things. And this is something that, Pascal mentioned.

532
00:19:53,555 --> 00:19:55,394
The Internet of Things is, a lot of

533
00:19:55,394 --> 00:19:56,994
people say, is one of the pillars of

534
00:19:56,994 --> 00:19:58,600
our 4th industrial revolution.

535
00:19:59,059 --> 00:20:02,039
Also, it's all about having many different devices

536
00:20:02,340 --> 00:20:04,740
that can communicate with each other via the

537
00:20:04,740 --> 00:20:06,119
Internet or via the cloud.

538
00:20:06,580 --> 00:20:08,340
And this embeds we'd like to say this

539
00:20:08,340 --> 00:20:10,980
embeds intelligence into infrastructure. What that means is

540
00:20:10,980 --> 00:20:13,634
that infrastructure can become more responsive.

541
00:20:14,015 --> 00:20:15,375
So if you think about a home, for

542
00:20:15,375 --> 00:20:18,255
example, you could have just a very rigid

543
00:20:18,255 --> 00:20:20,174
heating regime and be spending a lot of

544
00:20:20,174 --> 00:20:22,335
money on heating your home, or you have

545
00:20:22,335 --> 00:20:24,734
a more responsive, more adaptive heating regime depending

546
00:20:24,734 --> 00:20:26,869
on what the temperature is outside, whether it's

547
00:20:26,950 --> 00:20:28,250
there are any people in the room.

548
00:20:28,950 --> 00:20:31,509
And this can be enabled by having these

549
00:20:31,509 --> 00:20:34,230
wireless sensors that can detect where where the

550
00:20:34,230 --> 00:20:35,049
people are.

551
00:20:35,990 --> 00:20:38,150
Now the thing is the success of the

552
00:20:38,150 --> 00:20:39,769
Internet of Things is becoming

553
00:20:40,164 --> 00:20:42,325
a limitation as well because there's a, you

554
00:20:42,325 --> 00:20:44,505
know, because the success was there's an exponential

555
00:20:44,565 --> 00:20:46,244
increase in the number of devices part of

556
00:20:46,244 --> 00:20:46,984
this ecosystem.

557
00:20:47,525 --> 00:20:50,184
Right now, there's many billions of these devices.

558
00:20:50,644 --> 00:20:52,484
Many people project that there could be trillions

559
00:20:52,484 --> 00:20:54,484
of these devices in the future. So then

560
00:20:54,484 --> 00:20:56,909
how do you power these autonomous devices? You

561
00:20:56,909 --> 00:20:58,589
can't just plug them all into the wall

562
00:20:58,589 --> 00:21:00,669
because they could be located in very hard

563
00:21:00,669 --> 00:21:02,369
to reach places, for example, ceilings.

564
00:21:02,990 --> 00:21:04,990
So right now, the most common way is

565
00:21:04,990 --> 00:21:06,909
just to use a battery. But then if

566
00:21:06,909 --> 00:21:09,069
you have a trillion Internet of Things devices,

567
00:21:09,069 --> 00:21:11,055
you'd be throwing away a 100,000,000,000 batteries or

568
00:21:11,134 --> 00:21:13,134
trying to recharge ahead of 100,000,000,000 batteries every

569
00:21:13,134 --> 00:21:15,134
year. And if you think about the, drain

570
00:21:15,134 --> 00:21:16,975
pump resources that will take and the waste

571
00:21:16,975 --> 00:21:18,914
that will create, that's not really sustainable.

572
00:21:19,615 --> 00:21:22,335
So the alternative, the more sustainable route to

573
00:21:22,335 --> 00:21:24,539
power these Internet of Things devices is to

574
00:21:24,539 --> 00:21:26,299
harvest the energy that we get for free

575
00:21:26,299 --> 00:21:27,200
from our environment.

576
00:21:27,660 --> 00:21:29,259
And if you think about look around this

577
00:21:29,259 --> 00:21:31,360
room right now, you have this energy from

578
00:21:31,500 --> 00:21:34,140
mechanical vibration when people walk. There's heat from

579
00:21:34,140 --> 00:21:35,980
the radiators, so you can use something to

580
00:21:35,980 --> 00:21:37,980
harvest that heat. But by far, the most

581
00:21:37,980 --> 00:21:40,000
common source of energy is just from lighting,

582
00:21:40,195 --> 00:21:42,355
from indoor lighting or from ambient lighting, from

583
00:21:42,355 --> 00:21:44,914
windows, and you can harvest that energy through

584
00:21:44,914 --> 00:21:45,414
photovoltaics.

585
00:21:45,795 --> 00:21:46,775
And that's the idea.

586
00:21:48,355 --> 00:21:50,355
And right now, the the fuel's going through,

587
00:21:50,674 --> 00:21:53,119
you know, you know, like a rapid advance

588
00:21:53,119 --> 00:21:54,019
right now because,

589
00:21:54,399 --> 00:21:56,339
you know, for a long time the industry

590
00:21:56,399 --> 00:21:59,200
has been using amorphous silicon. So if you

591
00:21:59,440 --> 00:22:01,359
for anyone who's used a calculator with a

592
00:22:01,359 --> 00:22:03,599
solar cell built in, that's amorphous silicon. That's

593
00:22:03,599 --> 00:22:06,835
the most common commercial indoor photovoltaic device. But

594
00:22:06,835 --> 00:22:09,455
it has very limited efficiencies, usually below 10%.

595
00:22:10,235 --> 00:22:11,994
With some of the newer materials like lead

596
00:22:11,994 --> 00:22:14,875
Taylor Perovskites or dicensed by solar cells, those

597
00:22:14,875 --> 00:22:17,134
have now reached efficiencies beyond 30%

598
00:22:17,674 --> 00:22:19,990
and in some cases beyond 40%. So that's

599
00:22:19,990 --> 00:22:21,909
very exciting to have be able to produce

600
00:22:21,909 --> 00:22:24,230
enough power to power more complex Internet of

601
00:22:24,230 --> 00:22:24,970
Things devices.

602
00:22:25,589 --> 00:22:27,349
And just as a, you know, very simple

603
00:22:27,349 --> 00:22:29,750
example of of this application, so if you

604
00:22:29,750 --> 00:22:31,589
go to the supermarket, go to the clothing

605
00:22:31,589 --> 00:22:33,690
store, there's many paper tax around.

606
00:22:34,214 --> 00:22:36,694
And, you know, for these companies to become

607
00:22:36,694 --> 00:22:38,054
more sustainable, they can just get rid of

608
00:22:38,054 --> 00:22:40,134
all these paper tags and replace them with

609
00:22:40,134 --> 00:22:42,214
an electronic tag that displays the price. You

610
00:22:42,214 --> 00:22:43,654
can just keep using the same,

611
00:22:43,974 --> 00:22:45,750
tag for as they change their product,

612
00:22:46,309 --> 00:22:47,990
and these can be powered using an indoor

613
00:22:47,990 --> 00:22:49,750
PV device. You know, in the supermarket or

614
00:22:49,750 --> 00:22:51,990
in the clothing store, you have very constant,

615
00:22:51,990 --> 00:22:54,230
very reliable source of lighting. It can halter

616
00:22:54,230 --> 00:22:56,470
energy through a follow-up tech that powers it.

617
00:22:56,470 --> 00:22:58,404
And this is something that a lot of

618
00:22:58,404 --> 00:23:02,105
companies commercializing new photovoltaic materials are thinking about.

619
00:23:02,404 --> 00:23:04,244
I see. Yeah. Well, it sounds great. I

620
00:23:04,244 --> 00:23:04,984
suppose unless

621
00:23:05,285 --> 00:23:07,045
people think, oh, I better leave the lights

622
00:23:07,045 --> 00:23:09,204
on to power to power my Internet and

623
00:23:09,204 --> 00:23:11,204
things. Sure. Sure. You want to, use them

624
00:23:11,204 --> 00:23:13,079
in synergy with an energy storage device.

625
00:23:13,559 --> 00:23:15,720
So you have a PV device that has

626
00:23:15,720 --> 00:23:17,419
the energy and recharges the battery

627
00:23:17,720 --> 00:23:19,720
or instead, you can even just, replace the

628
00:23:19,720 --> 00:23:21,259
battery altogether and use a supercapacitor.

629
00:23:21,640 --> 00:23:23,799
That's more sustainable than a than a battery

630
00:23:23,799 --> 00:23:26,744
is. I see. Okay. Well, that's great. Thanks

631
00:23:26,744 --> 00:23:29,485
everyone. And I've got one last question

632
00:23:29,865 --> 00:23:32,184
that is for everybody. So we'll we'll go

633
00:23:32,184 --> 00:23:34,365
around the table with this one.

634
00:23:34,904 --> 00:23:37,065
One of the conclusions of the roadmap is

635
00:23:37,065 --> 00:23:39,920
that much more research will be needed before

636
00:23:39,920 --> 00:23:43,039
solar cells can meet their full potential in

637
00:23:43,039 --> 00:23:45,700
help helping us reach carbon neutrality.

638
00:23:46,640 --> 00:23:49,460
What is one thing that you think scientists,

639
00:23:50,079 --> 00:23:50,579
governments,

640
00:23:51,039 --> 00:23:54,339
and indeed the public can do to ensure

641
00:23:54,894 --> 00:23:57,214
that this happens? So, Nikita, do you wanna

642
00:23:57,214 --> 00:23:57,875
go first?

643
00:23:58,414 --> 00:24:00,275
So I think that's a loaded question,

644
00:24:00,974 --> 00:24:03,054
and I don't think there is one thing

645
00:24:03,054 --> 00:24:04,115
that's an answer.

646
00:24:04,414 --> 00:24:05,075
I think

647
00:24:05,535 --> 00:24:08,174
all of us have very different roles to

648
00:24:08,174 --> 00:24:08,674
play,

649
00:24:09,539 --> 00:24:11,460
in terms of being able to get to

650
00:24:11,460 --> 00:24:12,279
net 0.

651
00:24:13,380 --> 00:24:14,039
As academics,

652
00:24:14,339 --> 00:24:16,980
I think we're doing everything that we can

653
00:24:16,980 --> 00:24:18,039
do to

654
00:24:18,419 --> 00:24:19,399
make the technologies

655
00:24:19,859 --> 00:24:22,284
both viable and as cheap as we can.

656
00:24:23,384 --> 00:24:24,765
But at the end of the day,

657
00:24:25,304 --> 00:24:27,065
we still need a lot more funding for

658
00:24:27,065 --> 00:24:29,144
research because there's a lot more that needs

659
00:24:29,144 --> 00:24:29,884
to be done,

660
00:24:30,505 --> 00:24:32,345
in terms of what the government can do.

661
00:24:32,345 --> 00:24:33,720
They can invest in PV,

662
00:24:34,679 --> 00:24:36,299
because to a certain degree,

663
00:24:37,000 --> 00:24:38,679
we can do everything that we can do

664
00:24:38,679 --> 00:24:40,599
in the lab, but but there needs to

665
00:24:40,599 --> 00:24:42,519
be some sort of market drive and push

666
00:24:42,519 --> 00:24:44,279
in order for these things to be deployed

667
00:24:44,279 --> 00:24:46,059
at the rates that they need to be.

668
00:24:46,679 --> 00:24:49,259
I think one thing that is really

669
00:24:49,934 --> 00:24:52,255
kind of specific to perovskites in in a

670
00:24:52,255 --> 00:24:55,875
way is that most of these photovoltaic technologies

671
00:24:56,014 --> 00:24:57,855
that have been around and have been around

672
00:24:57,855 --> 00:24:59,154
for quite some time,

673
00:25:00,095 --> 00:25:02,835
they have kind of slower stages of development,

674
00:25:03,134 --> 00:25:04,815
which is one of the reasons why we

675
00:25:04,815 --> 00:25:07,650
have these TRLs or technology readiness levels.

676
00:25:08,350 --> 00:25:10,450
But perovskites are comparatively

677
00:25:10,830 --> 00:25:11,330
new.

678
00:25:11,710 --> 00:25:14,529
So let's say the real boom has been

679
00:25:15,230 --> 00:25:15,730
2013,

680
00:25:16,269 --> 00:25:18,485
2014 to now. So So it's really just

681
00:25:18,485 --> 00:25:20,965
a little over a decade, and we're in

682
00:25:20,965 --> 00:25:24,105
this really weird position where you have overlapping

683
00:25:24,485 --> 00:25:24,985
TRLs.

684
00:25:25,924 --> 00:25:27,765
So we're still in the lab doing very

685
00:25:27,765 --> 00:25:31,710
fundamental research, trying to understand how these things

686
00:25:31,710 --> 00:25:33,630
form, how they break, how we get the

687
00:25:33,630 --> 00:25:35,309
stability to where it needs to be in

688
00:25:35,309 --> 00:25:36,910
order for it to be out in the

689
00:25:36,910 --> 00:25:37,410
field.

690
00:25:37,710 --> 00:25:39,710
And then we have companies like Oxford PV,

691
00:25:39,710 --> 00:25:41,789
who have just sold the 1st perovskite silicon

692
00:25:41,789 --> 00:25:42,289
tandems.

693
00:25:42,634 --> 00:25:44,795
So in terms of funding, it's not about

694
00:25:44,795 --> 00:25:45,295
putting

695
00:25:45,755 --> 00:25:47,994
all your eggs in one basket. We need

696
00:25:47,994 --> 00:25:49,855
eggs in all of the baskets.

697
00:25:50,555 --> 00:25:52,394
And in terms of what the public can

698
00:25:52,394 --> 00:25:53,134
do is

699
00:25:53,595 --> 00:25:55,695
really just be more aware,

700
00:25:57,149 --> 00:26:00,509
invest, buy solar panels. And, you know, when

701
00:26:00,509 --> 00:26:01,329
the conversations

702
00:26:01,710 --> 00:26:04,269
about a solar farm being put out close

703
00:26:04,269 --> 00:26:06,509
to your house, realize that it's for a

704
00:26:06,509 --> 00:26:07,250
good cause.

705
00:26:09,095 --> 00:26:10,075
Okay. Thanks.

706
00:26:10,535 --> 00:26:12,234
And Sebastian, what about you?

707
00:26:12,615 --> 00:26:14,134
Well, I I I sort of want to

708
00:26:14,134 --> 00:26:16,715
double down on one point, Nikita made,

709
00:26:17,174 --> 00:26:19,494
which is to do with the investment that

710
00:26:19,494 --> 00:26:21,755
we need for research in solar.

711
00:26:22,890 --> 00:26:25,630
The governments in the UK and Europe,

712
00:26:26,250 --> 00:26:27,309
they they have to realize

713
00:26:27,930 --> 00:26:30,170
that solar has the potential to become a

714
00:26:30,170 --> 00:26:33,450
power generation industry of the similar size as

715
00:26:33,450 --> 00:26:36,565
fossil fuels are today. We have this phenomenal

716
00:26:36,625 --> 00:26:38,005
rise in the

717
00:26:38,384 --> 00:26:40,384
expansion of solar and it can range from

718
00:26:40,384 --> 00:26:41,525
everything from rooftops,

719
00:26:41,984 --> 00:26:43,045
utility scale,

720
00:26:43,505 --> 00:26:44,005
indoors,

721
00:26:44,625 --> 00:26:45,125
agriculture,

722
00:26:46,705 --> 00:26:49,105
and so on. So we really have a

723
00:26:49,105 --> 00:26:52,869
phenomenal opportunity to exploit this this expanded industry,

724
00:26:53,170 --> 00:26:55,569
and the UK is already needing in, in

725
00:26:55,569 --> 00:26:56,849
a lot of the research that has to

726
00:26:56,849 --> 00:26:57,670
do with solar.

727
00:26:58,130 --> 00:26:59,970
So we we really need to be able

728
00:26:59,970 --> 00:27:02,630
to capitalize on the on on those gains

729
00:27:03,009 --> 00:27:04,549
and continue to drive forward,

730
00:27:04,904 --> 00:27:05,644
that investment.

731
00:27:06,265 --> 00:27:08,424
Maybe also support the the the the point

732
00:27:08,424 --> 00:27:09,164
on the public.

733
00:27:09,785 --> 00:27:11,945
We can all we can also go to

734
00:27:11,945 --> 00:27:13,965
go to our energy bill and,

735
00:27:14,424 --> 00:27:16,265
and check how much of our electricity comes

736
00:27:16,265 --> 00:27:17,005
from renewables.

737
00:27:17,490 --> 00:27:19,009
And if it's and if we think that

738
00:27:19,009 --> 00:27:20,529
we can do more, then switch to a

739
00:27:20,529 --> 00:27:22,049
provider that can give you more,

740
00:27:22,450 --> 00:27:23,509
renewable electricity.

741
00:27:24,529 --> 00:27:26,630
And, Pascal, what would you like to add?

742
00:27:26,930 --> 00:27:29,250
Yeah. Just echoing what has been said before,

743
00:27:29,250 --> 00:27:31,384
renewable energy is a huge growth market at

744
00:27:31,384 --> 00:27:33,464
the moment. They will be the major power

745
00:27:33,464 --> 00:27:35,644
source in the future. Solar is gonna have

746
00:27:35,865 --> 00:27:37,964
a large or the largest part in that.

747
00:27:38,025 --> 00:27:40,345
And as a government, as a country, you

748
00:27:40,345 --> 00:27:42,424
probably want to own some of that technology.

749
00:27:42,424 --> 00:27:44,204
You want to have some of that domestically.

750
00:27:45,079 --> 00:27:47,820
That means you need sustained research input. Sometimes,

751
00:27:48,039 --> 00:27:50,279
there's a tendency as soon as stuff gets

752
00:27:50,279 --> 00:27:52,440
successful in the market, you kinda ramp down

753
00:27:52,440 --> 00:27:55,000
the funding. But then you miss the sort

754
00:27:55,000 --> 00:27:55,740
of fundamental

755
00:27:56,039 --> 00:27:59,265
input into the sustained growth of technology over

756
00:27:59,265 --> 00:27:59,765
decades

757
00:28:00,065 --> 00:28:02,065
that goes lost then. And and finally, you

758
00:28:02,065 --> 00:28:04,065
you need the talent. If you if you

759
00:28:04,065 --> 00:28:05,045
develop technology

760
00:28:05,505 --> 00:28:07,525
in a country, you need a con constant

761
00:28:07,585 --> 00:28:10,225
stream of talent into that sector, and that's

762
00:28:10,225 --> 00:28:12,325
what academic research certainly produces.

763
00:28:13,009 --> 00:28:15,250
And the last word goes to our host

764
00:28:15,250 --> 00:28:16,950
here at St. John's College,

765
00:28:17,329 --> 00:28:18,869
at Oxford, Robert.

766
00:28:19,329 --> 00:28:21,409
Yeah. I just want to absolutely support what,

767
00:28:21,569 --> 00:28:23,569
Pascal just said, which is it's very important

768
00:28:23,569 --> 00:28:24,825
we also invest in people.

769
00:28:25,865 --> 00:28:27,464
So, you know, we have the UK is

770
00:28:27,464 --> 00:28:29,144
probably one of the world leaders in terms

771
00:28:29,144 --> 00:28:32,125
of follow-up test research across the entire pipeline.

772
00:28:32,825 --> 00:28:34,744
But we need to, you know, have enough

773
00:28:34,744 --> 00:28:35,244
investment,

774
00:28:35,944 --> 00:28:38,345
in particular into, you know, the PhD students,

775
00:28:38,345 --> 00:28:39,804
the students who will be developing

776
00:28:40,589 --> 00:28:42,450
within our groups these new technologies.

777
00:28:42,829 --> 00:28:44,349
And right now, that's something that's a little

778
00:28:44,349 --> 00:28:46,429
bit lacking right now. There's, you know, there's

779
00:28:46,429 --> 00:28:49,970
no specific polyp polyamide specifically for developing photovoltaic.

780
00:28:50,190 --> 00:28:51,950
I think that really would be a missed

781
00:28:51,950 --> 00:28:53,904
opportunity because if you look at this road

782
00:28:53,904 --> 00:28:55,984
map, you know, of the 86 authors, the

783
00:28:55,984 --> 00:28:58,144
majority were from the UK. This is capturing

784
00:28:58,144 --> 00:28:59,984
the voice of the UK community and also

785
00:28:59,984 --> 00:29:02,305
shows the depth and breadth of expertise in

786
00:29:02,305 --> 00:29:04,144
the UK. And that's something that we should

787
00:29:04,144 --> 00:29:05,744
be proud of as a country, and that

788
00:29:05,744 --> 00:29:07,664
would that that's what we should be further

789
00:29:07,664 --> 00:29:08,339
investing in.

790
00:29:09,380 --> 00:29:11,059
That's great. Thanks. So I'd like to thank

791
00:29:11,059 --> 00:29:13,539
everyone for for coming out on this beautiful

792
00:29:13,539 --> 00:29:15,319
sunny day in Oxford.

793
00:29:16,179 --> 00:29:18,339
Yeah. Thanks so much for sharing your thoughts

794
00:29:18,339 --> 00:29:19,159
on sustainability

795
00:29:19,700 --> 00:29:23,159
and solar cells. Wonderful. Thank you. Thank you.

796
00:29:30,335 --> 00:29:32,815
That road map is published in the Journal

797
00:29:32,815 --> 00:29:34,195
of Physics Energy,

798
00:29:34,734 --> 00:29:37,634
and you can find it at IOP Science.

799
00:29:38,250 --> 00:29:39,630
Just search for the title

800
00:29:40,089 --> 00:29:42,589
road map on established and emerging

801
00:29:43,210 --> 00:29:43,710
photovoltaics

802
00:29:44,570 --> 00:29:45,470
for sustainable

803
00:29:45,930 --> 00:29:46,910
energy conversion.

804
00:29:47,690 --> 00:29:49,450
I'm afraid that's all the time we have

805
00:29:49,450 --> 00:29:52,544
for this week's podcast, which is supported by

806
00:29:52,544 --> 00:29:55,044
Pfeiffer Vacuum and Fab Solutions.

807
00:29:55,984 --> 00:29:57,605
Thanks to Robert Hoye,

808
00:29:57,984 --> 00:29:59,125
Nikita Noel,

809
00:29:59,744 --> 00:30:00,964
Pascal Kuyenberg,

810
00:30:01,504 --> 00:30:03,125
and Sebastian Bonilla

811
00:30:03,664 --> 00:30:05,125
for joining me today.

812
00:30:05,590 --> 00:30:08,309
And a special thanks to our producer, Fred

813
00:30:08,309 --> 00:30:08,809
Ailes.

814
00:30:09,350 --> 00:30:12,070
We'll be back again next week when we

815
00:30:12,070 --> 00:30:15,590
will be looking at 2 important aspects of

816
00:30:15,590 --> 00:30:18,650
space travel, the health effects of radiation

817
00:30:18,950 --> 00:30:19,769
on astronauts,

818
00:30:20,474 --> 00:30:22,494
and the need for an extraterrestrial

819
00:30:23,434 --> 00:30:26,734
time standard to keep missions on schedule.

820
00:30:29,674 --> 00:30:32,894
Thanks again to Pfeiffer Vacuum and Fab Solutions

821
00:30:33,355 --> 00:30:36,095
for supporting this episode of the podcast.

822
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Pfeiffer has been a globally established

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and highly competent partner in the development of

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sustainable

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solar cells and renewable energy technologies

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for many years.

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The company provides all types of vacuum equipment,

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including hybrid and magnetically

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levitated turbo pumps,

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leak detectors,

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and analysis equipment,

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as well as vacuum chambers and systems.

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You can explore all its products at pfeiffer

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vacuum.com.