The Solar Technology That Could Change Everything

[00:00:00] Speaker 1: I've been interviewing IDTechX analysts for a number of years now about perovskite, which is a mineral that gets added to solar panels to make them much more efficient. And Dr. Xiaoxi, could you give us an overview of your new report? Because it sounds like perovskite is finally being commercialized. [00:00:23] Dr. Xiaoxi: Yeah, and thank you very much for this great opportunity. In general, we have been tracking this technology and progress for quite a long time. And especially from recently, we see some changes. One change is we actually saw some commercial examples with increasing deployment and installations in different regions. And another very interesting observation is with the ever-increasing demand in the energy sector, people probably trying to explore new possibilities, which could be enabled by new technologies, including perovskite solar cells. And also this market really show very interesting region-dependent progress. So with some areas probably focus a bit more on technologies, others maybe closer or putting more effort on the manufacturers. And also, like as people probably already know, there are very different approaches, including the single junction, the tandem solar cells. And also sometimes people taking form factor or say the substrate flexibility into consideration as well. So this is generally some of the changes we have observed now. [00:01:46] Speaker 1: Now, for those folks who aren't familiar with perovskite, could you give us just a brief introduction to what perovskite is and how it works in the solar panel? [00:01:55] Dr. Xiaoxi: Yeah, sure. So perovskite is a kind of a material, it's an organo-inorganic combination and it was discovered in early times with a special structure of A, B, X, 3. So, for example, any material falling into the same structure would be called perovskite. And then they started their use as solar cell until like early times when people observed the initial efficiency around like 3.8%. And over like a decade and two decades, people just see the potential that their efficiency improves significantly. So they consider that would potentially be a really good replacement or complementary for the silicon solar cells. So people started to put more attention into this material. [00:02:48] Speaker 1: My understanding is that the average capacity, which I guess would be the percentage of the energy that comes from the sun, hits the solar panel, and then is converted into electricity, is generally around 20 or 22%. But with perovskite, it can be theoretical limits are around 36%, 39%. Have I got that correct? [00:03:13] Dr. Xiaoxi: Basically, the number may vary depending on whether we are talking single junction or tandem. So single junction theoretic limit, of course, that also depends on your calculation, could be around like 30%. But now most of the module, especially when we are talking about relatively large scale, probably numbers should even drop a little bit depending on who provide. Could range from like a 14% to a 19% in general for real application. And when we are talking about tandem, this number can actually be higher than the theoretic number. [00:03:52] Speaker 1: Well, let's get into the tandem solar cell, because I understand that that's leading the race to commercialize. Could you explain what a tandem cell is, the perovskite and silicon? [00:04:03] Dr. Xiaoxi: Yeah, just to make it simple, usually we have single junction, which is only based on like one kind of material layer for the solar light absorption. But in this case, you probably can simply understood as two different layers or even more layers. So they can observe some of the sunlight spectrum, leaving other parts to be observed by different material. So you're targeting different wavelengths, spectrum range, and that can actually boost your efficiency. If I just simplify the whole picture for the explanation. [00:04:42] Speaker 1: And is it fair to say then that the combination of perovskite and silicon in a tandem cell gets us up around the high 20% capacity? Is that where, is that achievable? [00:04:59] Dr. Xiaoxi: If we talk about efficiency, that can be even higher. It could be higher than 30%. [00:05:06] Speaker 1: And what does that do to the economics of a solar panel if you're getting that much more electricity from the same panel? [00:05:14] Dr. Xiaoxi: Yeah. So in some regions, for instance, when the real steam is very limited, for instance, on the rooftop, you don't really have enough space for solar cells. A very good way is to boost the efficiency. And also in some regions, like the installation fee actually play a more important role than the module price itself. So that means the human labor is more expensive. And that means if you can increase the efficiency, that can actually decrease the potential cost of the solar cell. So that makes a lot of sense. [00:05:51] Speaker 1: So, my understanding is that the commercial manufacturing is beginning, and there are many companies that are doing this, and it's probably the manufacturing, their skill and efficiency at manufacturing, that will bring down costs, increase the market, and then we'll see who the market winners are. Is that a fair way to describe that? [00:06:14] Dr. Xiaoxi: Yeah, I would say a very important new observation I have seen recently is really related to the manufacturing. Because quite a lot of records we see, for instance, from NREL, typically lots of them are based on the lab scale, like very small size of the module. But like when we come to real application, and when we increase the size of the module, usually efficiency will drop. So, any players who are able to manufacture that with a high yield and reliability actually has a better possibility to win in this game, say. [00:06:55] Speaker 1: What is the single biggest obstacle to perovskite gaining a foothold in the solar cell manufacturing industry? [00:07:05] Dr. Xiaoxi: So, I would say, for instance, people started to fix a kind of recipe, and also they gradually increased the yield, and then demonstrated the mass manufacturing capability. Also, we did some successful installation examples that just show people it works. Of course, what I talk about is there are single junction applications, as well as tandem trials, and there are also flexible module efforts. And they are all at different stages, but it just shows people some more hope, more possibility that could potentially work. [00:07:49] Speaker 1: Can you look out into the future, maybe the next year or two, maybe even five, and what do you expect to happen in this, you know, with perovskite in the solar cell industry? [00:08:00] Dr. Xiaoxi: Yeah. So, I think, first of all, silicon is still taking a very dominant position for now, especially single crystalline silicon. So, basically, my understanding is for quite a lot of applications, if a single crystalline silicon can work, that may still be the first choice. Only in some situations when silicon probably wouldn't be the best option, for instance, where we consider form factor, flexibility, and also the sunlight angle, a number of all different things. Then people started to show more perovskite, like niche applications in different areas, and it should have very special target. And that may receive more successful stories. And in the other time, depending on the region, people may still try single junction large deployment examples, like supported by the local government, for instance. And then that will hopefully try to expand the installation, and then try to further decrease the potential cost. And then hopefully, perovskite solar cells can gain more position in their future. [00:09:15] Speaker 1: So, I think it is. Is it fair to say that, you know, down the road, after the technology has proven itself in the marketplace, that we could be looking at capacity with those cells of well over 30%? Is that, you know, like a 35% or even 40%? [00:09:33] Dr. Xiaoxi: So when I talk about like 30% or something, it's actually the efficiency. Like when we talk about the installation, so say the penetration, I would say in the future, the actual penetration would be still at a very low number. The crystallizing still is an absolute dominant choice. So far, there is no very clear answer. This technology will definitely be successful, will grow bigger and bigger. But at least we saw some initial implications, and hopefully with more successful examples, we will see more penetration. But I don't really think like some 30% penetration rate would be, it's a very, very aggressive number in my opinion. [00:10:27] Speaker 1: Dr. Shaoxi, thank you very much for this. Really appreciate your insights. [00:10:31] Dr. Xiaoxi: Yeah, thank you so much. [00:10:33] Speaker 1: I'm happy to share our insights and opinions with you. [00:10:37] Dr. Xiaoxi: with you. Thanks.