Flexible solar cells to envelop zero-energy buildings. the buildings “zero energy” – that generate all the energy they consume, or more – are now closer to reality thanks to the feasibility of a long-awaited solar energy concept.
A team from Australia achieved the highest efficiency ever recorded in non-toxic, low-cost, flexible solar cells, that can be used to envelop the entire building, turning your walls into gigantic solar panels.
The promise of zero energy buildings is old, but has been running into two obstacles: the high cost of thin film solar cells, which can be manufactured by printing in roll format, and the fact that they are often made from expensive and toxic materials. – CdTe (cadmium telluride) e CIGS (copper-indium-gallium-selenide).
CZTS solar cells
Chang Yan and his colleagues at the University of New South Wales changed this by using an alternative thin-film technology known as CZTS, acronym of the elements that go into its composition: copper, zinc, tin (believe) and sulfur (sulfur).
In addition to being environmentally friendly, the flexible solar cells had the highest efficiency rate ever achieved in commercial-size cells of this type.
The efficiency index, from 7,6% in an area of 1 cm², has been confirmed by the US National Renewable Energy Laboratory.
Stacked solar cells
“In addition to its elements being more common and environmentally benign, we are interested in these CZTS solar cells for two reasons.: they can be deposited directly onto materials in the form of thin layers., that are 50 times thinner than a human hair, so there is no need to fabricate them on silicon wafers and interconnect them separately”, said Professor Martin Green, team coordinator.
“And they also respond better than silicon to the wavelength of blue light and can be stacked as a thin film over silicon cells to improve overall performance.”, finished.
Original text Tecnologic innovation