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Scientists Formulate New Method To Create Low-Cost High Efficiency Solar Cells (phys.org)
An anonymous reader quotes a report from Phys.Org: Scientists from the Energy Materials and Surface Sciences Unit at the Okinawa Institute of Science and Technology Graduate University (OIST) believe they've found a winning formula in a new method to fabricate low-cost high-efficiency solar cells. Prof. Yabing Qi and his team from OIST in collaboration with Prof. Shengzhong Liu from Shaanxi Normal University, China, developed the cells using the materials and compounds that mimic the crystalline structure of the naturally occurring mineral perovskite. They describe their technique in a study published in the journal Nature Communications. Perovskite offers a more affordable solution, Prof. Qi says. Perovskite was first used to make solar cells in 2009 by Prof. Tsutomu Miyasaka's research team at Toin University of Yokohama, Japan, and since then it has been rapidly gaining importance. The fabrication method he and his research team have developed produces perovskite solar cells with an efficiency comparable to crystalline silicon cells, but it is potentially much cheaper than making silicon solar cells.
To make the new cells, the researchers coated transparent conductive substrates with perovskite films that absorb sunlight very efficiently. They used a gas-solid reaction-based technique in which the substrate is first coated with a layer of hydrogen lead triiodide incorporated with a small amount of chlorine ions and methylamine gas -- allowing them to reproducibly make large uniform panels, each consisting of multiple solar cells. In developing the method, the scientists realized that making the perovskite layer 1 micron thick increased the working life of the solar cell significantly. In addition, a thicker coating not only boosted the stability of the solar cells but also facilitated the fabrication processes, thereby lowering its production costs. The team is now working on increasing the size of their newly designed solar cell prototype to large commercial-sized panels that can be several feet long. They have reportedly built a working model of their new perovskite solar modules, thanks to funding from OIST's Technology Development and Innovation Center, but "the process of upscaing has reduced the efficiency of the cells from 20% to 15%," reports Phys.Org. "[T]he researchers are optimistic that they will be able to improve the way they work in the coming years and successfully commercialize their use."
To make the new cells, the researchers coated transparent conductive substrates with perovskite films that absorb sunlight very efficiently. They used a gas-solid reaction-based technique in which the substrate is first coated with a layer of hydrogen lead triiodide incorporated with a small amount of chlorine ions and methylamine gas -- allowing them to reproducibly make large uniform panels, each consisting of multiple solar cells. In developing the method, the scientists realized that making the perovskite layer 1 micron thick increased the working life of the solar cell significantly. In addition, a thicker coating not only boosted the stability of the solar cells but also facilitated the fabrication processes, thereby lowering its production costs. The team is now working on increasing the size of their newly designed solar cell prototype to large commercial-sized panels that can be several feet long. They have reportedly built a working model of their new perovskite solar modules, thanks to funding from OIST's Technology Development and Innovation Center, but "the process of upscaing has reduced the efficiency of the cells from 20% to 15%," reports Phys.Org. "[T]he researchers are optimistic that they will be able to improve the way they work in the coming years and successfully commercialize their use."
In developing the method, the scientists realized that making the perovskite layer 1 micron thick increased the working life of the solar cell significantly.
Typical good quality crystalline silicon solar cells lose as much as 1% per year in efficiency, and lose as much as 15% efficiency in the first few months of deployment. This is why a 100 watt panel will typically produce as much as 120 watts for the first month or so, then taper off to 100 watts, then degrade slowly thereafter. This is one of the reason that to meet code, wiring for a solar installation must exceed the specs of the panels by around 20%. Now, my apologies if this isn't perfectly accurate, I've been intentionally hand-wavy as I've been out of the PV world for a bit.
Amorphous silicon is much, much worse, as it degrades as much as 10% per year, until they become opaque sheets of glass. This is why cheep Harbor Freight solar panels are cheap. Soon, they'll be just colored glass.
The manufacturing technique described in this article is similar to that of amorphous silicon, and the quoted sentence above glosses over a lot of ifs in the article. Still, I hope these researchers succeed.
Even if they don't, traditional silicon solar and some CdTe technologies are already at grid parity, so the current state of the art can already economically offset burning stuff to keep the lights on, or charge the electric car.
"Every time I see an adult on a bicycle, I no longer despair for the future of the human race." - H. G. Wells
The sun is not a reliable source of energy. The sun goes down every night, right when demand peaks, and then clouds can come in at any time to reduce output during the day. Addressing this with storage solutions costs money, which means solar power will be expensive even if the solar collectors themselves are cheap.
Energy storage solutions alone will not save solar power because such storage doesn't care if it is charged from solar power or anything else. Natural gas is a cheap source of energy, and natural gas boilers are a cheap and efficient way to turn that into electricity. The problem with boilers (natural gas, coal, or nuclear) is that they like to run at a nice and steady pace for best efficiency. Pair a boiler with storage and you get reliable power that can follow the changes in load throughout the day.
Cheap and efficient energy storage could in fact kill solar power, it just would not be able to compete with far more reliable energy sources to charge them up. I'm not sure even if solar power were free that it could compete because the demands for storage would still price it out of existence.