Energy is in the air! A chat with the nominee for the Global Energy Prize 2020 Dr Peidong Yang
Brilev: Hello everyone among the subscribers of the Global Energy Association. I’m Dr Sergey Brilev, the Head of the Association and this is the continuation of our talks with the people, who've been shortlisted for this year's prize. So, we've got today Dr Yang, who's joining us from California. Hello, Dr Yang.
Brilev: May I explain something to our viewers, I'm just back from Russia's main space museum, where on the 8th of September we'll be announcing the results of this year's nomination cycle. Dr Yang is among the shortlisted nominees and I should underline something very important. Yes, we are very proud of the fact that we have twice the number of nominations this year, yes, we've had some successful reforms, yet, Dr Yang is the only one, who was shortlisted last year and is shortlisted again despite all of the changes, which underlines the quality of his research. Dr Yang, we are to publish a book, which is called “10 breakthrough ideas for the next 10 years in energy”, in which a chapter is dedicated to artificial photosynthesis, which is your specialty, but when you think about your research, as I said… I can't… I couldn't believe my eyes when I read about you: energy bacteria, solar power. How do they come together? Just explain it for certain that are listening to us now.
Yang: Yeah. Thank you. So, what we are trying to do nowadays is really trying to learn from nature. So, essentially what we are doing is called as artificial photosynthesis. So, in these artificial photosynthetic systems, if we want to convert solar energy and store them into chemical energy, that requires certainly light of absorber. Something, that absorbs solar energy that also requires some catalyst to do the chemistry for us. So, that's where all the sort of our original design of artificial photosynthetic system, that based on our semiconductor nanowires in combination with some of the best biological catalysts. In some of our cases is these bacteria are doing the chemistry for us. So, in our photosynthetic system, artificial photosynthetic system, our semiconductor nanowires they are great solar energy light absorber. It's just like solar panel. We have many decades of experience in the solar panel design in the past. I would say the whole scientific community has been working on that for 50-60 years. So, semiconductor is robust and they can capture the solar energy. Once they capture the solar energy and they will pass on those energy to these biological catalysts to do the chemistry for us so that these biological catalysts can fix CO2 and convert them into useful chemicals like acetate, like a butanol, like a polymers or even pharmaceutical drug intermediates. And that's what we are doing nowadays and that's why sometimes I very much caused these this process, as well generating this so-called liquid sunlight. Different sound means that you take the solar energy and using these photosynthetic systems and store them into solar energy. Basically, in one step, we are using our artificial photosynthetic system to convert directly the solar energy and store them into the chemical bond.
Brilev: I couldn't quite believe my eyes, I can't believe my ears now. But you're certainly telling the truth. Give me five seconds, because I'm going to show you a secret weapon of today. Of course, as is the Covid-19 happens to be nearby…So, let's imagine I sneeze...Aha …and there's plenty of bacteria here. Where do you get yours from?
Yang: Oh. Okay, so we're using very different sort of bacteria. So, in the Covid-19, there is virus, in our photosynthetic system when we are talking about this biological catalyst, all these bacteria, these are sort of denied bacteria that utilize their life basically, utilize CO2 and convert them in one of our cases…
Brilev: But do you produce those organisms in the laboratory or you actually get somewhere in nature?
Yang: We get these bacteria from nature. And many of these bacteria is existing in soil. And I want to emphasise, actually, the bacteria we are using to start with, that do not have photosynthetic capability, meaning, that they don't have light absorbing capability, but they do have the CO2 chemistry sort of machinery. So that their sort of CO2 conversion chemistry is wonderful, but however they don't know how to get those energy from. That's where our semiconductor nanowire coming from. These our semiconductor nanowire basically gives them the living space. These highsurface cellular semiconductor structure gives this bacterial living space, while the semiconductor nanowire absorbs the solar energy and pass on energy to these environmentally benign bugs. Then we're combining the best of the two worlds: the semiconductor side do the light absorbing, then the biological catalyst to do the chemistry for us. In combination we have a fully integrated system that generating our sort of liquid sunlight in the end.
Brilev: Will there be a day when you gather some dust in your front garden you put an artificial leaf in your courtyard and you start getting electricity?
Yang: Well, in the future, I think what's going to happen. It is based on our original sort of concept of this combination of the semiconductor nanowire structure with these best biological catalysts. I think in the future you could imagine, that these, something like a little bit like a solar panel, putting on the roof. This combination of photosynthetic system can do the same thing as the solar panel, except the solar panel is the solar energy to electricity, while these photosynthetic systems are doing one thing, that's converted solar energy into liquid sunlight or liquid fuel. So, that's, I think in the future, that's one can imagine, that's going to happen.
Brilev: The reason why I asked this question and thank you so much indeed for mentioning solar panels is the following. I had the family, well, it wasn't a family dispute it was a family get-together a couple of weeks ago, when my wife and I were deciding, whether it's worth putting exactly solar panels over the roof of our house. And after careful calculations we came to a conclusion, that as of today, this is certainly very important, as of today, it's basically there's no difference, whether I put a solar panel, or I put a generator. Of course, by putting a generator for emergency electricity supply, obviously, I will harm the environment. This is undoubtful, although batteries from solar panels harm environment too, but the question was twofold. Firstly, the climate, because of course in Moscow we are, roughly, where Canada is, so, you know, unfortunately, oil-based generators are more reliable, than solar panels. But, also, the cost, as of today it's roughly equal even with advanced technology of solar panels. Looking at your technology how expensive is the watt produced with your technology as compared to a watt of electricity produced, based on the traditional electricity generation.
Yang: I think this is a very good question. Whenever, there's a new technology, coming out, there's always issue about the cost and the efficiency. But first of all, I think we need to realise, that traditionally when we're using, we're burning the fossil fuel. Well, certainly, we're releasing CO2 of doing harm to the environment, that's why we are doing all these renewable energy technologies. But developing new technology are solving the CO2 problems, solving this sort of environmental climate change. Solar panel nowadays actually is very efficient. In the unit in the silicon panel you can easily get 20 percent above energy conversion efficiency and the cost is going down. So, solar panel is basically starting to gett into the market fairly rapidly after more than 50-60 years of research and production. But solar panel is the process, that doing the solar to your electricity, meaning that you needed to integrate with the grid. That's certainly one issue, that's why, many people are working on energy storage like battery.
Brilev: Absolutely, yes, this is the constant, running in all of our conversations with everyone.
Yang: So, what we're doing now is basically we're trying to come up with the technologies to solve this problem in one step. Well, basically solving the solar energy conversion and the storage in one step, meaning that, that's why I emphasise, what store the solar energy into the chemical bond and in the chemical bond, the energy density is high, just like in the generator. Basically, you are burning these chemicals to release those energy. That's why traditionally we are using. So, our process is doing exactly the same thing. And, of course, when we're burning our sort of gasoline, those gasoline is something we're taking out of from the ground, basically we dig out of the fossil fuel and come up with the gasoline and then we drive our car. And that is a form of a solar energy, stored in the chemical bond, but only happens in millions millions of years. For our process, we're doing this in the lab. Hopefully, in one day it can be scaled up. Once you scale this thing up, then you can think about the chemical industry, energy industry and the pharmaceutical industry. Because the current chemical energy and the pharmaceutical industry all placed on the fossil fuel chemistry, because all those carbon is coming from underground. Now if our chemistry can be scaled up, all those carbon now is coming from the environment, from the CO2 in our atmosphere, but the rest is the same, the rest of chemistry is the same, but the energy now is also from sunlight. So, this is fundamentally I think a different technology, that will revolutionise the sort of the energy and the chemistry and the pharmaceutical industry in the many decades down the road.
Brilev: So, in the past and presumably in the future “love is in the air” typically according to a song, but now “energy is in the air”.
Yang: Yes, energy is in the air. That basically with the sunlight and the CO2. Exactly, you're right.
Brilev: How does your artificial leaf look like. Is it like a leaf a green one?
Yang: Well, it actually fundamentally looks like a solar panel. Yeah, exactly I mean, we have these sort of arrays, high density arrays of these silicon nanowires, where it's like a tiny tiny forest. It's a high density. Then within those three-dimensional space you have. These biological catalysts living inside. This kind of wafer you can basically eradicate with the sunlight then give it CO2, it will produce these chemicals for you.
Brilev: Okay, well, let me tell you a story we had among the co-founders of the prize and one of the first winners - academician Alferov, who once, 12 years ago, invited me to visit his university in St Petersburg. It is a very interesting university, where people study, and there's a lot of research, which is not very typical for Russian universities. So, we were going through all those labs and I decided to start asking a very simple question to everyone we’ve met, I was asking them about their profession, their occupation. And I started receiving very interesting unthinkable answers. So, people were saying to me, okay, I am a graduate of a Medical University, but I'm a nanotechnologist; and the other one was saying, I am a chemistry faculty graduate, but I have nothing to do with chemistry, nothing to do with physics, something parallel. And they couldn't really describe their occupation, they were saying to me, my occupation is post number 2 in this lab , because I don't really know who I am, I am a physicist, a biologist, a medical doctor, I don't know, but I’m looking forward to getting these results, combining different sciences. Who are you? What are you?
Yang: Okay, so this is a very important question. That's relevant to many of us, who are working on energy science in order to solve these energy sort of problems like CO2 conversion, combating these climate change, you need actually the knowledge base, coming from many different disciplines, in order to solve this very big challenging issue, we're facing. The science become more and more interdisciplinary. So, I consider myself… like my bachelor's degree in chemistry, then my PhD degree at Harvard is chemistry plus applied physics, then more and more I'm getting into material science nowadays. So, you need this sort of knowledge base that builds field by many decades of research in the in this entire scientific community, then you will come up with this very much cross-disciplinary solution to solve these issues. Our photosynthetic system is exactly a good example, where we're combining two disciplines, that traditionally does not mix with each other, the semiconductor side under the biological catalyst side. Precisely, combine them together we come up with a really interdisciplinary solution to this big, big challenging environmental and energy problem we are facing.
Brilev: Good. Well, I'm wishing good luck to all of our participants and to Dr Yang among them. Thank you so much indeed.
Yang: Yeah, thank you.