Butterfly Wings Inspire Solar Panels

Photo courtesy: e³°°°/CC BY-SA 2.0

University of Pennsylvania Engineering Professor Shu Yang and her team have mimicked the reflective and water-resistant properties of butterfly wings to create a material that could coat solar panels and increase their output by keeping them clean and dry. The efficiency of solar panels takes a major drive when moisture and debris collect on their surface, so this inventive nature-inspired solution could keep them working at their maximum efficiency, not to mention the iridescence would be beautiful to look at.

New Scientist explains how Yang made the holographic wafer material:

"Yang used holographic lithography to recreate the wings' reflective properties, using a laser to make a 3D cross-linked pattern in a kind of material called photoresist. A solvent then washes away all the photoresist untouched by the laser, creating the 3D structure that affects light to create the colour effects. Then a poorer solvent roughens the surface, creating the texture that makes butterfly wings water-resistant."

Photo courtesy: © Advanced Functional Materials

The holographic material could also be used to coat buildings. While this wouldn't have any clean energy applications, Yang does see them as a way to make buildings more beautiful. The coated buildings could be connected to a chip that lets the owners change the color and transparency.

Yang is working under a grant to produce the hydrophobic coating for solar panels. A prototype of the material should be ready by June 2013.

High-Speed European Train Goes Green

The tunnel on the Paris-Amsterdam high-speed rail line is topped with 16,000 solar panels. Photo courtesy: SPS2900 via TreeHugger

The 2 gigantic solar farms just launched in France are part of a much wider push for large-scale solar and renewables going on in Europe right now. In fact, the same company responsible for these farms has today unveiled a huge 1MW solar tunnel that will protect trains from falling trees (reducing the need for tree felling), and provide power to one of Belgium's most important railway stations in the process.

The high-speed line running from Paris to Amsterdam passes Antwerp and a nearby ancient forest. To avoid the need to fell protected trees, a long tunnel was built over the line which has now been topped with 16,000 solar panels. The electricity produced is equivalent to that needed to power all the trains in Belgium for one day per year, and will also help power Antwerp station.

"For train operators, it is the perfect way to cut their carbon footprints because you can use spaces that have no other economic value and the projects can be delivered within a year because they don't attract the protests that wind power does," said Bart Van Renterghem, UK head of Belgian renewable energy company Enfinity, which installed the panels.

"We had a couple of projects lined up around London with train operators and water utilities, but they have been put on hold."

Van Renterghem said this was due to the UK government's controversial review of subsidies for large-scale solar power projects, which will lower the returns available.



The video above gives a sense of scale of the tunnel. Enfinity, the renewable energy company behind the project, was also due to build similar projects along train lines around London. But Bart Van Renterghem, UK head of the company, told the Guardian that these plans are currently on hold pending the Government's review of feed-in solar tariffs for large scale energy production.

The UK government argues that solar technology is too expensive, but Van Renterghem said he had seen the cost of cells halve in the last two to three years thanks to economies of scale in Germany, France and Belgium.

The new Blackfriars station in London, which will span the River Thames, will host the largest single collection of solar panels in the UK when it opens in spring 2012.

The roof of the new station will have 4,400 panels and a capacity of 1MW, enough to provide 50% of the station's electricity. However, the development is not dependent on the level of government subsidy for solar power as the £7.3m ($12m USD) bill was paid by the transport department's environment fund.

Via TreeHugger and guardian