Flexible photo voltaic panels are simply nearly as good as common ones

Light-weight and flexible photo voltaic cells which can be simply as environment friendly as typical ones may massively broaden using solar energy.

Most photo voltaic cells in use right this moment are crystal silicon-based, because of their excessive effectivity and ease of manufacture, however they’ll solely be positioned on flat, static surfaces as a result of they crack underneath stress. Present flexible photo voltaic cells created from different supplies provide another, however at the price of a lot decrease power effectivity.

Now, Wenzhu Liu on the Chinese language Academy of Sciences in Shanghai and his colleagues have developed a skinny, light-weight silicon-based cell that’s so versatile it may wrap round itself with out dropping any effectivity.

The workforce created the cell by first thinning a photovoltaic silicon wafer by greater than 60 per cent, which makes it as flexible as paper, but additionally reflective and so much less environment friendly. Chemically treating the floor to create microscopic, pyramid-shaped bumps restores this effectivity, however makes it brittle when bent – till Liu had an concept to repair that.

“One day, when I tore a plastic food bag, the small notch on the bag’s edge inspired me to ask whether the tendency of silicon cells to fragment with mechanical stress is caused by sharp notches on the edges of the wafers,” he says.

After filming the handled cells snapping in gradual movement, Liu and his workforce realised that the cracks would begin on the fringe of a cell in channels between the pyramids. After they softened these channels and tried bending a cell, they discovered that a number of tiny, superficial cracks amassed however the cell didn’t break, and it retained its effectivity.

The flexible cells may be simply fabricated utilizing present silicon wafer strategies and, as a result of they’re 95 per cent lighter than inflexible cells, might be used on partitions with out compromising constructing integrity. Liu and his workforce examined the cells in excessive environments – akin to on the South Pole, on a drone flying at an altitude of 20 kilometres and on a balloon in excessive wind – and located they labored as nicely and typically higher than inflexible photo voltaic cells.

Kyle Frohna on the College of Cambridge says the work could be very spectacular. “It opens silicon up to a whole other class of applications, some of which we’ve thought of and some of which we probably haven’t even thought of yet.”