Tuesday, 12 June 2012

Thin-Film photovoltaics market aims to convert on huge potential

5 Jun 2012

Ultimately, the world will run out of fossil fuels. Meanwhile, as the world fights over fossil fuels, our planet hangs in space a mere 93 million miles from a giant fusion reactor that's 1.4 million km wide. The sun gives us about 1.37 kilowatts per m² of energy. If it were somehow possible to convert 100% of the sun's energy into usable power, we would need only one hour of it to power the Earth for an entire year.

Using the sun for energy is hardly a new concept. Nor are photovoltaics (PV), which convert sunlight into electricity; the technology has been under commercial development since the 1970s, though up until recently, it remained difficult to achieve economies in manufacturing to make PV affordable. To date, solar panels large enough to fulfill significant energy needs have been neither very cheap nor very portable.

While the military has developed folding, semi-portable solar panels for installations in remote locations, few organizations or individuals have the kinds of budgets of the Department of Defense. Not to mention that most solar panels to date have been opaque, rigid and hard to use in places that could use a little supplemental energy from PV: atop a car or a building's windows.

The future practicality of PV--lower price point and putting PV cells onto less rigid surfaces so they can be "wrapped" or molded around buildings, cars and even people, in the form of PV-cell clothing--seems to lie in making PV cells flexible. Enter the plastics industry and the development of thin-film solar cells (TFSC), also called thin-film photovoltaic (TFPV) cells. TFSCs are made by depositing one or more thin layers, i.e., films, of photovoltaic material onto a substrate. The thickness of the layers is small, ranging from a few nanometers to a few tens of micrometers. Existing thin-film processes generally use semiconductor materials such as copper, indium, gallium, cadmium and selenium to create the PV cells.

Read More…