Scientists working on a joint project have devised a pretty cool way to make solar panels self-cleaning and produce more power. By adding a nanoscopic pattern to the surface of the solar cells, they found that not only does the pattern make the cells non-reflective (which boosts the power output of the cell), it also makes the surface of the cell non-stick and self-cleaning.
The researchers, part of a joint project between Changchun University of Science and Technology (China), Xi’an Technological University (China), and Cardiff University (UK), developed the tiny pattern, which traps sunlight in the cell instead of reflecting it back out. The etched nano sized pattern also makes the cell behave much like a water-repellent lotus leaf – nothing sticks to it, and when it rains, any dust, dirt, bird droppings, etc just get washed off.
Unused land sitting at a municipal city landfill in Massachusetts is now being put to productive use – saving money and generating clean electricity.
The city of Methuen put their Huntington Avenue landfill to green productive use by building a small solar farm on the site. The new solar farm, which is now connected to the electrical grid and is producing power, consists of 5,156 solar panels that generate enough electricity to power about 250 houses.
Borrego Solar Systems, Inc – the company that built and is operating the farm, will lease the land from the city for the next 20 years. By granting Borrego Solar access to the landfill, Methuen gets electricity from the solar panels at below market rates, which the city predicts will save it about $80,000 per year.
A group of researchers at the Fraunhofer Institute for Applied Optics and Precision Engineering along with a team from the Friedrich-Schiller University are working to develop new cost efficient solar panels available in a wide range of colors. By combining what should be an aesthetically pleasing design along with highly efficient solar cells, the teams hope to get architects and designers interested in using solar panels as part of new construction.
The team came up with semiconductor-insulator-semiconductor (SIS) solar cells made from paper-thin crystalline silicon wafers. Their SIS cells have an insulator layer made from an optically neutral barrier that has a hundred-nanometer thick transparent conductive oxide (TCO) coating serving to guide photons to the semiconductor layer below it. An added bonus is that the TCO layer has a lower refractive index than silicon, so the SIS cells reflects much less light. By changing the thickness or the refractive index of the TCO, they can change the color of the solar cell, and the team found that the TCO coating has barely any impact on the efficiency of the cell. They think that they can hit 20% efficiency with their cells.
The team is currently developing an inkjet printing process that will deposit the TCO layer directly on the silicon semiconductor wafer. Using an inkjet printing process should make the entire manufacturing process faster and more flexible.
Apple is building a new data center in Reno, Nevada, and they’re planning to powering it with 100% renewable energy. Plans call for a 18 megawatt photovoltaic solar farm to be built in Yerington, which is right outside Reno. The new solar farm will completely power Apple’s new data center and also provide electricity to the local power grid.
The Fort Churchill Solar Array will consist of 137 acres of concentrating PV solar panels. Apple’s partnering with NV Energy, Inc for the construction. They’re figuring it will take about eight months to build.
Sheerwind, the wind power company based in Minnesota, has just released the results of tests on their INVOLEX bladeless wind turbine, and the results are very encouraging. Their testing shows a 300-600% increase in wind power generated compared to traditional type wind turbines.
The INVOLEX is a ducted wind turbine that captures and concentrates the wind from any direction and channels it to a turbine located on the ground. Sheerwind claims higher output at lower wind speeds along with decreased installation and maintenance costs (since the turbine is located at ground level rather than several hundred feet up in the air, and you don’t need to build and transport massive turbine blades).
Last December, Sheerwind announced the completion of their first large scale prototype, and last week they came out with the results of testing. Over the course of testing in various wind conditions, they’re claiming that INVOLEX can produce an average of 314% increased power output over traditional wind turbines. Depending on wind conditions, they saw increases from 81% to 660%, with the average increase being 314%. Sheerwind says that their INVOLEX wind turbine can generate power at very low wind speeds, as low as 1 mph. Their turbines are much smaller than other wind turbines, and Sheerwind is claiming a low installation cost of about $750 per KW.
In announcing the testing results, Sheerwind CEO Dr. Daryoush Allaei said, “This exciting performance superiority over traditional wind and competitiveness with natural gas and hydroelectric generation is attracting significant interest from fortune 500 and moderately sized companies; government entities; industry experts; and others. Our ability to operate efficiently and effectively in areas never considered viable with traditional wind energy and at costs as low as $10 MWH makes SheerWind a true game-changer in electric power generation.”
Based on the results of testing, Sheerwind is targeting next year (2014) for the deployment of utility scale INVOLEX turbines.
Reviews of the new 2013 Volkswagen Jetta Hybrid are starting to hit, and it seems like all reviewers are giving it very positive reviews – while not getting as great gas mileage as the Prius, it sounds like its a lot more fun to drive. The New York Times is calling the new VW Jetta hybrid “an affordable, fuel-efficient Volkswagen aimed at the large market of family-car buyers.” Here’s some links to the reviews, if you’re interested:
By combining their experience on cooling supercomputers with a concentrated photovoltaic solar collector, IBM thinks that they can hit 80 percent efficiency with its new High Concentration Photovoltaic Thermal (HCPVT) system. With HCPVT, you get energy in two forms – electricity plus hot water.
The system consists of a mirrored parabolic dish that tracks the sun to focus sunlight by a factor of 2,000X onto triple-junction solar cells. Each solar cell converts up to 30 percent of sunlight into electricity. Of course magnifying the sun’s rays by 2000 times is going to generate a whopping amount of heat, and that’s where IBM gets its system up to 80 percent efficiency. IBM developed a thermal cooling system for HCPVT based on the cooling design for its Aquasar supercompter. Built into each unit are tiny micro-channels filled with water that carry away heat from the solar cell, and this heat can be used to provide hot water, or heat buildings, or provide the energy to purify water.
So far, IBM’s built a small prototype HCPVT system, which consists of 4 small (1-cm square) solar cells, each generating about 200-250 watts. Overall, the prototype generates about 1 kW of electricity. Their next step is to build a larger system with a 100-square meter dish that would crank out about 25kW of electricity plus hot water.
IBM has also put a lot of thought into reducing the cost of its system, by using low cost materials wherever possible. For example, instead of using steel to build the parabolic dish, they will make it out of concrete, which is then covered by simple pressurized metalized foils. While the higher-tech components of the system need to be made centrally, IBM feels that the dish and the rest of the construction and assembly can be done at the same location the system will be used. That means lower costs and local jobs.
In the video below, Dr. Bruno Michel of IBM explains more about the HCPVT system.
Based on an idea from his ten year old daughter, nanotechnologist David Carroll of Wake Forest University has developed a flexible thermoelectric fabric he calls Power Felt that generates electricity from both heat and movement. There’s been other thermoelectric products made before, but they’ve usually been made out of ceramic material – heavy, brittle, and expensive. Power Felt is thin, lightweight, and feels just like wool felt – it’s even washable, as Carroll found out by accident. It’s cheap too – it costs about a quarter to make enough to cover a laptop.
Right now he’s envisioning using Power Felt to help extend the life of a battery. If it’s embedded in a laptop casing, then the heat that the laptop generates would be recycled back into the battery. Putting it on the back of a cellphone and letting your cellphone bounce around in your pocket (and absorb body heat) would put some juice back in the battery. But he’s also thinking about much bigger applications. For example, if Power Felt is cheap enough, it could be wrapped around your house, just like Tyvek insulation is now. All houses leak heat – with Power Felt you can use that heat loss to generate power. Making it part of a solar cell means that you generate electricity both from sunlight and the heat that the solar cell absorbs.
Carroll says that he hopes to make Power Felt commercially available by next year, and that they’re in the process of signing contracts with various companies to make it – he can’t name names, but he says that “the chances are extremely good that they make something that’s in your house right now.”
If you want to read more, Business Insider has a couple of articles on David Carroll’s Power Felt along with some short interviews.