Breakthroughs in Solar Cell Technology from Australia and South Africa

Photovoltaic solar cells are poised for much greater utilisation, worldwide. According to The Energy Blog, the costs of solar power will be cut in half by 2010, and cost comparable to nuclear energy by no later than 2030.

News reports from researchers in Australia and South Africa suggest that the price reductions may even occur sooner than the predictions of mainstream energy analysts suggest. At the University of Queensland, plastics and nanotech crystals are replacing the silicon in the solar cells--greatly reducing potential production costs.

UQ Master of Physics student Michael Deceglie is working on improving the stability and overall efficiency of solar cells.

Mr Deceglie is testing two new ways of making solar cells out of dye-sensitized solar cell and a combined nanocrystal polymer solar cell.

The dye-sensitized cells use dye molecules to inject electrons into a thin titanium dioxide film while the polymer cell is a thin film of plastic mixed with microscopic crystals that channel the charge through the cell.

Mr Deceglie said both methods could produce solar cells that had similar efficiencies to current silicon technology but were cheaper more flexible, easier to produce and more environmentally friendly.

“Since electrons don't move well in the polymers, we incorporate nanocrystals with the polymer to provide a pathway along which electrons can move to generate electrical current,” Mr Deceglie said.

“The dye-sensitzed device works in a manner similar to phosynthesis in plants.”

Source.

South African researchers have developed another alternative approach to photovoltaic solar cells, using a unique metal alloy in flexible, very thin layers.

In a scientific breakthrough that has stunned the world, a team of South African scientists, led by Professor Vivian Alberts, has developed a revolutionary new, highly efficient solar power technology” and “The South African solar panels consist of a thin layer of a unique metal alloy that converts light into energy.”

The photo-responsive alloy can operate on virtually all flexible surfaces. The new panels are approximately five microns thick (a human hair is 20 microns thick) while the older silicon panels are 350 microns thick. Alberts claims the cost of the South African technology is a fraction of the cost for less effective silicon solar panels.”

This claim is corroborated in today’s story in the South Africa Mining Weekly, where alongside the report about Eskom’s solar thermal project there is this: “The University of Johannesburg’s Professor Vivian Alberts, from the department of physics, has developed solar panels that may just take this technology further into the main-stream, owing to the cost reductions he has achieved.

Alberts’ invention is five micro-metres thick, combining several semiconductor materials which are as effective, if not more so, than silicon. As it uses no silicon, costs are dramatically lower. It makes use of normal window glass as a substrate, with molybdenum applied as back contact, followed by the core component, being a compound semiconductor comprising five elements - copper, indium, gallium, selenium and sulphide, replacing the silicon - with cadmium sulphide as a buffer layer, followed by an intrinsic zinc oxide layer and, finally, a conductive zinc-oxide layer. The most expensive part of the panel is the glass,” said Alberts.

Source.

Hat tips to keelynet.com and what's next in scitech.

The high cost of solar cell grade silicon has driven the production costs of photovoltaics upward. But scientists and engineers are always looking for ways to improve technology, to get around the roadblocks to economic utilisation. See this Energy Blog article for information about a new silicon feedstock for photovoltaics.

When eminent scientists predict that something is impossible, they are almost certainly wrong. Thomas Kuhn merely reminded us of something that young innovators have known throughout human history--sometimes the older scientists with vested interests in the old ways of thinking have to die off, before humans can move on.