Currently, there are many different types of solar cells on the market: cadmium telluride, copper indium gallium selenide (thin-film), monocrystalline silicon, polycrystalline silicon, and amorphous silicon. Of these materials, silicon solar cells have dominated the market for decades. However, we may be seeing a new material come into the market soon— Perovskites.
What are Perovskites?
Perovskite-based solar cells use perovskite crystal structures commonly composed of hydrocarbons, lead, ammonia, and halogen compounds. Perovskite solar cells fundamentally work the same way as other solar cells – cells accept photons that convert into DC energy.
Researchers have reported that the perovskite solar cells are estimated to surpass traditional mono-/poly-crystalline silicon cells inefficiency, as lab efficiencies have already reached above 20 percent for perovskite solar cells. With more testing and engineering, researchers believe that perovskite solar cells will breach the efficiency limits of traditional silicon-based solar cells.
Aesthetics & Functionality
Aside from efficiency, perovskite solar cells have physical qualities that give them a competitive edge. These cells have high flexibility, low-density, are translucent and come in a thin-film material. Such material creates a highly aesthetic appeal, but they provide a functional potential of being integrated into buildings and residential roofs. Furthermore, they can also be integrated into “tandem cells,” which are solar cells that are composed of both perovskite and silicon materials to reap the benefits that both provide and the ability to produce more energy.
According to researchers from the Massachusetts Institute of Technology, the upward scalability of perovskite solar cell production is feasible, and the raw materials are inexpensive. The manufacturing process will be a less tedious production process than that of silicon solar cells because they can be printed in a roll-to-roll process, similar to printing newspapers. Such qualities will reduce the transportation and installation costs of the product as well. In contrast, silicon solar cells come from silicon ingots that are sliced into thin slides that are meticulously processed into a power converting product – a costly process.
The Future Of Perovskites
However, with such promising science on the potential to provide better value than what is currently on the market, the biggest hurdle for the entry of perovskite solar cells revolves around the capital needed to switch from silicon production to perovskite production. The funds necessary for utility-scale production of perovskite solar cells would require an initial investment in hundreds of millions to billions of dollars.
Ian Mathews, a postdoc from MIT, predicts that this cost can decrease to a sensible initial investment in the order of $40 million through the right business strategy. As Matthews puts it, labs that are developing perovskite-based solar cells claim, “very low costs. But they’re claiming it once your factory reaches a certain scale. And I thought, we’ve seen this before — people claim a new photovoltaic material will be cheaper than all the rest and better than all the rest. That’s great, except we need to have a plan as to how we actually get the material and the technology to scale.”
Mathews, along with research scientist Marius Peters, professor of mechanical engineering Tonio Buonassisi, and five others at MIT, Wellesley College, and Swift Solar Inc., have all done research on Perovskite Cells. They predict that the initial investment needed to manufacture and sell perovskite solar cells can be significantly reduced by starting in niche markets and then expanding into utility-scale production. These niche markets would mainly be composed of “prices people might get in the internet of things, or the market in building-integrated photovoltaics. People usually pay a higher price in these markets because they’re more of a specialized product.”
As perovskite solar cells prove to be a technically and profitably viable business venture within its niche markets, the scalability to move into other markets will become less expensive.
While perovskite solar panels are not available for sale yet, high-efficiency silicon solar panels are. The efficiency of silicon solar panels is continually increasing, and technology is steadily advancing. For example, Solaria has developed a shingle-style silicon cell that enhances the panel’s ability while reducing the number of bus bars, materials, and size of the panel. Another example would be panels from Hanwha, which incorporates “split-cell” technology into their PV modules, which reduces the size of the solar cells to fit more cells into a panel, heightening the efficiency and performance potential.