A new kind of solar cell could give windows the ability to generate electricity. The polymer solar cells (PSCs), developed by researchers at the University of California, Los Angeles (UCLA) absorb mostly infrared, not visible, light, making them almost 70 percent transparent to the human eye.
The cells are made from a photoactive plastic that converts infrared light into an electrical current, according to an article in ACS Nano that describes the research. Applications could include high-performance, visibly transparent photovoltaic (PV) devices, such as building-integrated PV and integrated PV chargers for portable electronics, said study leader Yang Yang, UCLA professor of materials science and engineering, and director of the Nano Renewable Energy Center at California NanoSystems Institute (CNSI).
A new kind of polymer solar cell that is almost 70 percent transparent to the human eye could give windows the ability to generate electricity by absorbing mostly infrared, not visible, light. (Source: UCLA)
PSCs aren't entirely new, but truly transparent ones are. Previous attempts to make PSCs that are partially or completely transparent to the naked eye have either resulted in devices that are transparent to visible light but not very efficient, or efficient devices that aren't really transparent. The researchers say that this is mostly because the devices were not fabricated with the best combination of polymeric PV materials and efficient transparent conductors. For example, opaque metal electrodes have typically been used.
The UCLA PSCs are lightweight, flexible, and have a maximum transparency of 66 percent at 550nm. They incorporate near-infrared (NIR) photoactive polymer and use a highly transparent silver nanowire-metal oxide composite conducting film as the top transparent electrode. The NIR light-sensitive photoactive polymer balances transparency at visible wavelengths by harvesting solar energy from NIR wavelengths while being less sensitive to visible photons.
The transparent conductor is a major breakthrough, the researchers say. It's made of a mixture of silver nanowire and titanium dioxide nanoparticles. This composite electrode makes it possible for the PSCs to be fabricated in high volume at low cost, via mild solution processes. The transparent PSCs have a power-conversion efficiency of 4 percent.
Other authors of the study are CNSI director Paul S. Weiss; CNSI postdoctoral researcher Yue Bing Zheng; materials science and engineering postdoctoral researcher Rui Zhu; doctoral candidates Chun-Chao Chen, Letian Dou, Choong-Heui Chung, Tze-Bin Song, and Steve Hawks; and Gang Li, former vice president of engineering for Solarmer Energy Inc. The study received funding supported from the Henry Samueli School of Engineering and Applied Science, the Office of Naval Research, and The Kavli Foundation.
Not much to it, really. I took an off the shelf electric mower and added some panels to charge batteries. I've since replaced the very heavy SLA cells with a 10AH NiMh pack, and that makes the machine much easier to navigate. It takes about three good days to recharge the cells, so sometimes I mow on a particular day to make sure I get a good solar harvest.
William, windows may not generate a lot of power on their own. But with conventional electricity produced by fossil fuels, we have been conditioned to think of only a single power source technology. With alternative energy sources, the idea is often to combine different power sources and with multiple energy inputs. I've become more aware of that mix living out in the forest with electricity for lights and powering the ceiling fan (for cooling and heating), a woodstove for heat, and propane for hot water. So the idea of getting energy in a single building from solar and wind, for instance, and from window films plus panels on the roof, or those plus passive solar collection methods, makes sense.
I agree with Mydesign about the investment in active PV solar being worth it over the long run. However, homeowners have to be able to afford the several thousands of dollars investment and not everyone can do it. Regarding solar panel thickness, yes, that's one of the whole points of this project.
William, all the natural energy conservation methods require a little bit upfront investment and we can have a fair ROI in long term. The immediate ROI is less because, we are using the generated power for domestic use and it has to be calculated according to the tariff sheet provided by the local energy distributor. I had done a similar calculation before going for solar power to my house and it found that it will take minimum 20 years for cover up the initial investment cost. But have the proud that am using natural resources and no need to worry about tariff hike or power cuts.
Ann, the normal Solar panels are of thick in size and it cannot be used other than fix in terrace of buildings. If the thickness is less and of comfortable size, they can be fixing in outside walls and window doors. So most of the people may prefer and in turn more natural energy can be produced.
This is an interesting concept indeed. But aside from the discussions about relative efficiency, how much useful power is a window-cell going to produce? Then, consider the logistics of transporting the power from a window that can open, because some folks do open windows for ventillation at times. Finally, consider the expense of the hardware needed to convert whatever power is produced to a voltage-current level that can actually be useful.
My whole point is that what we have here is an interesting developement that may not be "worth the effort" to implement it. At that point it becomes valid to question how much effort and resources should be expended in that direction.
All kinds of passive storage methods have been developed, many of them in the 70s and 80s, some more recently, Most of them derive from building designs that are thousands of years old. This is not new technology.
I don't think a smart grid is needed. Some of the original solar power designs in the 70s were passive: the power generated is used by the building that generates it. You don't need a smart grid to do that.
A new service lets engineers and orthopedic surgeons design and 3D print highly accurate, patient-specific, orthopedic medical implants made of metal -- without owning a 3D printer. Using free, downloadable software, users can import ASCII and binary .STL files, design the implant, and send an encrypted design file to a third-party manufacturer.
A recent report sponsored by the American Chemistry Council (ACC) focuses on emerging gasification technologies for converting waste into energy and fuel on a large scale and saving it from the landfill. Some of that waste includes non-recycled plastic.
Capping a 30-year quest, GE Aviation has broken ground on the first high-volume factory for producing commercial jet engine components from ceramic matrix composites. The plant will produce high-pressure turbine shrouds for the LEAP Turbofan engine.
Seismic shifts in 3D printing materials include an optimization method that reduces the material needed to print an object by 85 percent, research designed to create new, stronger materials, and a new ASTM standard for their mechanical properties.
A recent study finds that 3D printing is both cheaper and greener than traditional factory-based mass manufacturing and distribution. At least, it's true for making consumer plastic products on open-source, low-cost RepRap printers.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.