Solar technology, getting cheap electricity by converting the sun’s energy via solar devices, is one of the big future hopes for green renewable energy in the century ahead. There are 3 main competing technologies at work, although I have a hunch that they will conflate in the years ahead. The furthest advanced is solar-thermal technology, where mirrors or mirror like surfaces focus the sun’s energy in heating a central core, which exchanges its heat in a heat exchanger to produce steam to run steam turbine generators. At present such large projects generally require large subsidy.
The next technology is solar cell panels which can be placed in the deserts or on the roofs of large buildings like Walmarts, to generate some of the power consumed in the building. Scaled down it can be adapted for use in homes. The trick is being able to compete internationally against China.
The third competing solar technology is solar film. Intended to be applied to the structure of buildings to generate electricity from the building itself. None are yet at the level of compelling economics although there have been big advances in their conversion efficiencies in the last 5 years that suggest, all three are on the cusp of a commercial breakthrough.
The latest breakthroughs have come in solar films and panels, thanks to the introduction of graphene. I think it is only a matter of time this decade, before thin film solar and solar panels, make the efficiency breakthrough that will turn local solar produced electricity into one of the wonders of our new carbon age. Solar power, produced and stored locally, can have a lifestyle transformational effect in the third world, not just in the affluent first world. The long term future for graphite just grows with each passing month.
Physicists Set New Record for Graphene Solar Cell Efficiency
ScienceDaily (May 24, 2012) — Doping may be a no-no for athletes, but researchers in the University of Florida's physics department say it was key in getting unprecedented power conversion efficiency from a new graphene solar cell created in their lab.
Graphene solar cells are one of industry's great hopes for cheaper, durable solar power cells in the future. But previous attempts to use graphene, a single-atom-thick honeycomb lattice of carbon atoms, in solar cells have only managed power conversion efficiencies ranging up to 2.9 percent. The UF team was able to achieve a record breaking 8.6 percent efficiency with their device by chemically treating, or doping, the graphene with trifluoromethanesulfonyl-amide, or TFSA. Their results are published in the current online edition of Nano Letters.
"The dopant makes the graphene film more conductive and increases the electric field potential inside the cell," said Xiaochang Miao, a graduate student in the physics department. That makes it more efficient at converting sunlight into electricity. And unlike other dopants that have been tried in the past, TFSA is stable — its effects are long lasting.
As previously reported in April.
Graphene Boosts Efficiency of Next-Gen Solar Cells
ScienceDaily (Apr. 24, 2012) — The coolest new nanomaterial of the 21st century could boost the efficiency of the next generation of solar panels, a team of Michigan Technological University materials scientists has discovered.
Graphene, a two-dimensional honeycomb of carbon atoms, is a rising star in the materials community for its radical properties. One of those properties is electrical conductivity, which could make it a key ingredient in the next generation of photovoltaic cells, says Yun Hang Hu, a professor of materials science and engineering.
—-In dye-sensitized solar cells, photons knock electrons from the dye into a thin layer of titanium dioxide, which relays them to the anode. Hu's group found that adding graphene to the titanium dioxide increased its conductivity, bringing 52.4 percent more current into the circuit.