November 20, 2013
Host: Ted Simons
AZ Technology and Innovation: ASU Solar Energy Research
- A national project promising a significant advance in technology for converting sunlight into electricity will be led by a team of Arizona State University engineers. With a $3.5 million grant from the U.S. Department of Energy’s SunShot Initiative, the team will develop new ultra-thin silicon solar cells designed to increase the amount of electricity that can be produced through direct conversion of sunlight. Stuart Bowden, the ASU team leader, will discuss the research.
- Stuart Bowden - ASU Solar Energy Research
| Keywords: ASU
Ted Simons: Tonight's focus on Arizona technology and innovation looks at a national project to advance the ability to convert sunlight into electricity. The project will be led by a team of ASU engineers. Leading that team is Stuart Bowden, who joins us now. Good to have here.
Stuart Bowden: Thank you very much.
Ted Simons: This is a national project, solar cell efficiency, what are we talking about?
Stuart Bowden: Solar cells are a great technology. You have this crystal, and you shine light on it and electricity comes out. It does not get simpler than that. But one of the challenges and one of the sort of our job as a team, that I'm leading, is how can we maximize the amount that we can get out of that crystal? So in the past, the amount of electricity might have been like a curiosity, something you might have seen in children's toys, but now, it's a real industry. So, what is a really interesting statistic, over the last 30 years, the cost of photovoltaic has come down by a factor of 100, so it's sort of this niche market, sort of unreal that we can put it on our roofs. What that means in, say Arizona, in a lot of places, it's cost effective. So put it on the roof, and it will pay back over the life of the system. But it’s not true everywhere, so parts of the country, which unfortunately, aren’t as sunny as Arizona, and what we're doing, we're going that extra bit, which is taking the cost down by another factor of two. And we’re doing that by increasing the efficiency, and to do that, we need a large team of people.
Ted Simons: There increasing the capacity and the efficiency to capture or to store?
Stuart Bowden: It's to capture. So, what we're doing is we're increasing the efficiency of when the sunlight comes in, and how much comes out.
Ted Simons: And how much will be stored because it's a cloudy day for the next week.
Stuart Bowden: Right, always a cloudy day and always a bit of a challenge.
Ted Simons: Does this mean thinner cells? Or what's the plan?
Stuart Bowden: What we did here is, is we sort of went back to the fundamentals of photovoltaics. And we've been making photovoltaics the same way for the last 20 years, and we use a lot of technology, which came from the integrated circuit industry, computer chips. And that's great, if you are making chips because you can make those expensive and still make lots of money; Intel still does pretty well for themselves. But for photovoltaics, the whole cost structure is really different; we need to make things cheap, really cheap. So we said, “Okay, there are some processes that we are seeing in the way we make these that are a bit expensive. How can we go back to the fundamentals?” So we went back to thermodynamics, which sort of governs the way everything works, and we looked at that and said, “Okay, we’re going to come up with a new device design, new device physics that will enable us to get higher efficiency, but without increasing the cost.” So, it's a, a higher efficiency device, but, it's simpler to make.
Ted Simons: Is it -- is it just a new design without new materials, or are new materials involved?
Stuart Bowden: What we're doing is we're involving some new materials, but the base technology that we are using is crystalline silicon. So the PV panels you see all around the city, most of those, a lot of those are made from crystalline silicon. So we're combining that, really cheap material, a really well-known material, it's really stable, so we are combining that with some newer materials. So, we sort of figure this is important because we get the stability, the known sort potential some of the existing materials, but combine that with new materials that enable us to get much higher performance.
Ted Simons: So you are not reinventing the wheel but making it more efficient, more streamlined.
Stuart Bowden: So the nice thing about this is you don't have to restart everything, go right back to how do you refine silicon and how do come up with the whole industry, there is a big industry for that, which we can leverage. And what is actually nice about this is the way that we're doing these new device physics, we sort of – most semi-conductor activity at the moment, it's fabricated by either a diffusion or a deposition of other materials, and we found that that was limiting the device performance. So with this new device design, we're able to, as I said, when you shine light on a crystal, you get the charges, electrons and holes, and what we want to do is get those electrons out, and we are able to pull the electrons out without any losses. And the jargon is we pull them out.
Ted Simons: Well, yeah, and when you are pulling them out here, are you pulling them -- is the advancement, is it, are we talking big-time exponential increase?
Stuart Bowden: We don't need exponential increase in efficiency. With this project we'll be taking the systems from 20 to 25%, and you think, well, it's not going to make much difference. But, if you look at the economics of it, if you are at 15%, you just can't sell them. So 20% is about where you start making money. 25% you start to make pretty big in-roads. But what's more interesting is that we know, through the similar device designs, that we can get up to 86%. So that will be an enabling technology, so that's kind of the next project.
Ted Simons: And indeed, it sounds like the goal, as you referred to earlier, making solar more economically competitive. And when does it become more economically competitive?
Stuart Bowden: That's a good question. And it depends on who you ask. So, I've been in photovoltaic since I was an undergraduate, so, I've been working in it for a while. And if you work in photovoltaic, you get the question, do you have PV on the roof. It's one of those things, like most homeowners, have a few things to deal with, and plumbing, but it's just last week, I finally signed up for the photovoltaics, so, I figure out the economics were enough and I could justify it enough for the family, it's economics. So, it's a ten-year payback, which I was comfortable with, and maybe a few people are comfortable with, and what we want to do is reduce that down, so that for everyone, it's a no-brainer. It’s like installing an air-conditioning system, you think, “Okay.”
Ted Simons: And talk quickly about advancing the integration of solar into the grid. Where does that stand now? What can be improved technologically?
Stuart Bowden: Yeah.
Ted Simons: Or otherwise?
Stuart Bowden: It's going to be a challenge. The industry is changing. Any large industry that changes, it's always going to cause some disruptions. The phone industry is probably an example we like to follow. And they went from having a fairly centralized fixed system, and now, you have mobile phones for everyone. When mobile phones first came out, they are viewed with a suspicion, you know, there is these funny things. But now, they are ubiquitous, and we can see this happening with the electricity grid; they are going from a centralized system to more of a cellular system. So the same reason we call the mobile phone system a cellular system, we'll see that with photovoltaic and will be tied into the smart grid concept.
Ted Simons: I feel like we're on the cusp of advances, and enough to get you involved to putting them on the roof.
Stuart Bowden: It's enough to get me to put them on the roof. My mom got there first.
Ted Simons: Good for her, and before you go, MIT Universities in Australia, Switzerland, and how did ASU get involved in this?
Stuart Bowden: ASU is the lead for this project. We started a center at ASU, four years ago, and we built up enough technology, we got a few world records, and we have a pilot line where we have the students to come by, and make solar cells. And we just went out there and attract the other partners, talked to them, said ok, what technologies can you bring to it. So each partner brings the technology. And the University of New South Wales in Australia gets involved, part my background being Australian. By bringing together the technologies, and we find these with photovoltaic, it's a worldwide industry, you need people from everywhere to make a contribution.
Ted Simons: Congratulations. Good luck on the project. And congratulations on the new addition to the house.
Stuart Bowden: Thank you very much.
Krauss on Science
- Arizona State University physicist Lawrence Krauss makes his monthly appearance on Arizona Horizon to talk about the latest science news, including news on dark matter.
- Lawrence Krauss - Physicist, Arizona State University
| Keywords: science
Ted Simons: Good evening and welcome to "Arizona Horizon." I'm Ted Simons. The state will receive a part of a national settlement with google over alleged privacy violations. The settlement splits million between states, and involves allegations that google use an advertising loophole to track the online activities of millions using web browsers, the state attorney general's office announced Arizona's portion of the system. No word on how the money will be allocated.
Ted Simons: And southern Arizona congressman Ron barber announce he would be running for re-election. He expressed some hesitation about another run but tells the Arizona Capitol Times that he's committed to keeping his seat in Arizona's second congressional district.
Ted Simons: Every month ASU Physicist Lawrence Krauss joins us to talk about the latest science news. Even if the news is that there is no news. Here to explain is Lawrence Krauss. And you are saying that this is not necessarily a bad thing.
Lawrence Krauss: No news is good news.
Ted Simons: Right.
Lawrence Krauss: As I was saying, although you disagreed, sometimes it's better to be right than sexy, sometimes. Because what's interesting, this is one of the most important mysteries around. What's the stuff that dominates, the mass of our galaxy and we think it's a new particle, and there are these detectors, and they are really difficult experiments, because they are looking for one event a year, you know, with a very small amount of energy to deposit a detector because these dark matter particles don't interact with normal matter or with light for example. I know you will be talking about solar energy later, but these particles don't interact with the sun, so in the whole, they go through the Earth without interacting, and you have to build very sensitive detectors. The day after we had our last meeting here, I guessed, and I am happy to say I guessed right, they would not see anything, and rarely will I guess on TV. But the other observation, and there have been some by groups in Italy and other groups in the United States, have all produced one or two events, but the radioactive backgrounds are all over the place, and they just didn't smell right. If they had been right it would have been astounding. But, I think that it's really good that this experiment, in the whole, has shown that we don't have to worry about those, we don't have to invent baroque models to explain the dark matter, and the kind of dark matter that we think is out there, is more likely going to be harder to find, and we'll discover it or in fact, this detector, that announce the negative results is the first generation of the whole new type of detector, I'm involved in one collaboration, and noble gases, which are pure because noble gases don't combine with any other element, so you can get very low rates of activity. And those detectors are the new generation of detectors, and this one was small but they are going to be built up to one to ten tons, and will look and maybe one of them will get a signal that could be confirmed.
Ted Simons: So reading about this, it sounds like not only did they find nothing but they found clear nothing, which is good thing because it means the process seemed to work.
Lawrence Krauss: Exactly, when you are at the edge, in fact, last time we talked about this, the edge of what you can detect, and when you are at the edge of what you can detect, you don't know when you see something if it's significant or not. If you are building a detector to detect one event a year and you see that, is it an accident or radioactive background? So, what this detector could do was statistically show, with very convincingly that they ruled out all the other observations, which were not wrong. But they were just bad accidents. They were just unfortunate occurrences radioactivity or something.
Ted Simons: So what does that mean about dark matter theory in general?
Lawrence Krauss: Well, it means that we still don't know what it is, which is really the most important thing it, means that everything is up for grabs, and we're virtually certain it's a new type of particle, but it does mean that the kind of theories that may be tested at the collider, will produce events which would not have been detectable in the current set of detectors. They are too low of a rate. But, you will need the bigger detectors if, all goes well, these detectors and collider, there is a race, whether we produce dark matter with the accelerators, or whether we measure the matter from the beginning time, and there is a race. If we are lucky we may see it in both places at the same time confirming that it's there and then we'll know the makeup of 90% of the mass of the universe, and we'll have learned that 90% of the mass of the Universe is made of something different than and I are made of, which is amazing.
Ted Simons: It is amazing. And quickly, for reference purposes here, we're talking about possibly, we think that these are subatomic particles left over from the big bang? It's like smoke going through a screen door kind of thing?
Lawrence Krauss: You can call it that. There are sub atomic particles, and there are lots of them around, called nutrinos. There are 300 per cubic centimeter left over from the big bang, but we have never been able to detect them because they interact to weakly. We know they are there, but we have not figured out a way to detect them. So there is lots of stuff, more are than meets the eye, and that makes the world an exciting place.
Ted Simons: And that means we have got to keep looking. Alright, who is Craig Venter?
Lawrence Krauss: A very interesting scientist, who happens to be on the advisory board our origins project, and will be here in April when we have our big fifth anniversary.
Ted Simons: He will demand to be on the show.
Lawrence Krauss: He's very, very, iconic classic scientist. But he led, as you may remember, when they were first sequencing the human genome, the national institute of health was doing it and Frances Cohen, the current director of the institutes health was leading that effort. Then this Renegade individual said that I can do it with my company, and I can sequence the human genome as fast, and in fact, Craig Venter did, and since he's proposed a lot of interesting ideas. Basically, doing synthetic biology to build new organisms, which might produce oil, and do all sorts of things. But, he does it in a very, very colorful way. He took his own sailboat around the world, to look for new organisms in the oceans which he found. This week, he did another, one might say media show, but it's interesting, he talked about, about basically, teleporting life, but not in the star trek way. But he argued that, for example, on Mars, we may have devices which detect some kind of life form which detect fossilized life form. And eventually you could build something that would sequence the DNA, if there was DNA of that life form. And as we can now sequence things, that used to cost a million dollars to sequence it, now it cost $1,000. Eventually you might be able to do it in a short time, and he said he would build it here on Earth so he would not have to have rocket ship carrying it back. He could transport the information. Which is, a very sensible thing, and they have done that. When, when their viruses, his team earlier last year, or the year before when there was a virus strand discovered on the other side of the Earth, they sequence the DNA of that strand, and he built it, and the laboratory built a vaccine for that virus.
Ted Simons: So it's like a biological fax machine?
Lawrence Krauss: It is, and I mean, it sounds good and the point is it's not that new, and it's package in a way to make it sound exciting, and namely to use for an exciting possibility such as the discovery of life elsewhere. But what it does point out is that our ability to both sequence viruses and build them in the laboratory, is interesting. One of the things that he did was, was, basically, build from scratch, more or less, atom by atom or molecule by molecule, following the sequence of DNA, build a Gene, insert it in an organism where they knocked out the other genes, and the new organism grew.
Ted Simons: Yes.
Lawrence Krauss: And so, basically, it's like he created a new form of life, not quite because he copied it. But what we're doing in synthetic biology is amazing, and not what we are, but he and other people are doing, and he promotes it in a very big way. But, it really means our ability to- for example, he talked about- in the same conference, where he was talking about mars- about faxing a vaccine at home basically. Because if we have genetic sequencers, we could basically send the instructions over the internet, and have a tabletop genetic sequencer attached to the computer that could read the instructions and produce the DNA, and you could have your own antibiotic, so you would not have to go to the store and buy it, you may be able to build it at home.
Ted Simons: But that's reality. Let's get back to the transporter, the converter. Can you synthesize an entire genome? That seems like heavy stuff.
Lawrence Krauss: It's not clear you’ll be able to do it for a while, but just think about what you could not do- the computation, it's very demanding and almost unfathomable. But, I remember 40 years ago when I taught at Yale, I had the largest hard drive at Yale. And one gigabyte cost me $25,000 and now I have a key card here that has ten gigabytes for nothing. So, I think that it points out that the possibilities are amazing, and the idea of DNA, as a software, as well as hardware, namely that it's just a genetic code, and if you could reproduce the code, and get the materials at the same time, you could build new systems. It's not quite teleporting but, it is nevertheless fascinating, and in fact what we'll do here in April, I hope, is run a meeting on redesigning humans.
Ted Simons: That would be fantastic.
Lawrence Krauss: So it will be fascinating.
Ted Simons: We need to get him on the show.
Lawrence Krauss: Get rid of the back problems, just redesign humans without those problems.
Ted Simons: I would like to redesign some humans.
Ted Simons: The Kepler space telescopes, I thought that this thing was damaged and out there and limping around.
Lawrence Krauss: It's an amazing telescope that has told us, it founded in principle maybe, 3,000 planets, and which is just amazing because it's telling us that, in principle, there could be lots of habitable planets around other stars, some estimated 30 billion. Namely Earth-like planets, in our galaxy, which should mean, that's obviously important for, for knowing if we are alone in the universe. But, unfortunately, it's become hobble and --
Ted Simons: What happened to it?
Lawrence Krauss: And what happened is that in order to be able to -- what it does, stare at lots stars. Every night, in one region of the galaxy, and they have to be in exactly the same Mace because every night it compares the image of the next night versus the first night and, and pixel by pixel, looking to see if the light in the star changes a bit, if a small planet goes in front of the star, and it's amazing that it works. But, in order for it to work, it has to point incredibly accurately and has to have the gyros that keep it pointing in the same direction. Two of those have gone kaput. So it can't continue to point accurately because the problem is, it gets its power from solar panels. And it's an angle to the sun, and the solar pressure, the pressure of the lights and the sun keeps wanting to kick it off its direction, and without these extra wheels to keep it there, it cannot look any more at that region of the sky. So, you might say darn, we just throw it out, but it's this incredible telescope. It still works so maybe we can use it for something else. And the engineers have got a neat idea, why don't we just point it with its back to the sun, so that the solar pressure is displayed evenly on all the panels. And then the sun will, basically, keep it pointing in the same direction. And now, of course, as it goes around the sun, it will, therefore, point in different directions around the galaxy, and so, it won't be looking at that region, but it can do other things. It can look for other kind planets, in other regions, or it can look in distant galaxies, sometimes the field of view will be in different galaxies. All it does is look for variations in light. So anything that produces variations in light will be interesting. One of them, for example, could be new kinds of variable stars, but also exploding stars in other galaxies. Or, planets around stars that it happens to be pointing at for a short time. It has to be very close, so the orbit would have to be days rather than months.
Ted Simons: I was going to say, how long can it be in that one position? It cannot be as stable as it used to be.
Lawrence Krauss: That's why it can't look for Earth-like planets. To find the Earth, you would have to measure it over several years because it takes years for it to go around the Sun. What they would like to do is look for planets that might be habitable, or at least there can be liquid water. If the star is much smaller, the planet could orbit closer and still be in the habitable zone, and that orbit might just take weeks, and they will be able to move slowly enough that they might be able to look at a single region of the sky for a period of weeks to see a planet go around the stars.
Ted Simons: Mentioned supernovas, can see planets being born, all of this stuff?
Lawrence Krauss: Exactly. They are looking for changes in light, so the regions of the galaxy where stars are being born now, the regions of other galaxies where they are exploding, and so they made all sorts proposals to use this telescope. It's up there after all and now, none of them -- it hasn't been approved yet because it will still take money to run this thing. But, it would be a shame to take this telescope that's out there, and functional, and not say well, ok, let's use it for a different purpose. That's what we do in science all the time. We build device and is say, it turns out for some reason or another, it does not work for what we thought it was, but let's find something out to use it for, and that's --
Ted Simons: And this space telescope, this is really -- we have learned a lot from this.
Lawrence Krauss: It told us more than we, in all of history about the possibility planets, and told us more about the likelihood we're not alone. I think it's an amazing device, and we should celebrate it, and it would be a shame to just turn it off.
Ted Simons: All right. Well, it's good to hear from you. I am sorry that we had to start with a negative story, but it was --
Lawrence Krauss: It's not a negative story.
Ted Simons: We turned it into positive.
Lawrence Krauss: Not seeing something directs everything. The University has to work on the Michaelson-Worley experiment that did not see the Earth moving around the sun when it was measuring light. That laid the basis for a special relativity. So, not seeing things in science is sometimes very important. It's just harder to get Congress to pay for it and harder to say, guess, what we did not see anything, will you give us more money.
Ted Simons: Good to see again, neighboring for joining us.
Lawrence Krauss: Thanks.