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A new discovery from a chemist at the University of Texas at Austin may allow photovoltaic solar cells to double their efficiency, thus providing loads more electrical power from regular sunlight.

Carrier multiplication (CM) is a process in which absorption of a single photon produces not just one but multiple electron-hole pairs. This effect is a potential enabler of next-generation, high-efficiency photovoltaic and photocatalytic systems.

very nice approach ...

The link didn't work for me. Try that one: http://www.pnas.org/content/early/2009/11/18/0907390106.abstract?sid=348d3f4f-cc68-47e8-9099-a3310134ae68

The idea has been around for already some time (2008) but I like it despite the challenges/trade-off: visible vs IR photovoltaics, black leaves would be better... Piezo + classical PV would already be great... Optimizing the leave shape & distribution for both wind and sun energy harvesting could be interesting...

some biomimicry used in energy systems... maybe it sparks some ideas

not much new that has not been shared here before ... BUT: we have done relativley little on any of them. for good reasons?? don't know - maybe time to look into some of these again more closely Energy Efficiency( Termite mounds inspired regulated airflow for temperature control of large structures, preventing wasteful air conditioning and saving 10% energy.[1] Whale fins shapes informed the design of new-age wind turbine blades, with bumps/tubercles reducing drag by 30% and boosting power by 20%.[2][3][4] Stingray motion has motivated studies on this type of low-effort flapping glide, which takes advantage of the leading edge vortex, for new-age underwater robots and submarines.[5][6] Studies of microstructures found on shark skin that decrease drag and prevent accumulation of algae, barnacles, and mussels attached to their body have led to "anti-biofouling" technologies meant to address the 15% of marine vessel fuel use due to drag.[7][8][9][10] Energy Generation( Passive heliotropism exhibited by sunflowers has inspired research on a liquid crystalline elastomer and carbon nanotube system that improves the efficiency of solar panels by 10%, without using GPS and active repositioning panels to track the sun.[11][12][13] Mimicking the fluid dynamics principles utilized by schools of fish could help to optimize the arrangement of individual wind turbines in wind farms.[14] The nanoscale anti-reflection structures found on certain butterfly wings has led to a model to effectively harness solar energy.[15][16][17] Energy Storage( Inspired by the sunlight-to-energy conversion in plants, researchers are utilizing a protein in spinach to create a sort of photovoltaic cell that generates hydrogen from water (i.e. hydrogen fuel cell).[18][19] Utilizing a property of genetically-engineered viruses, specifically their ability to recognize and bind to certain materials (carbon nanotubes in this case), researchers have developed virus-based "scaffolds" that

Using random nanostructuring highly absorptive materials were made which are of interest for photovoltaic or thermovoltaic applications

Yes! Black Metal... definitely something the ACT should look into

Black Metal...sounds like something for the ACT Magic Cards. But apart from that - is it possible to shift the PV type of absorption into gamma ray spectrum?

Inserting a droplet of polymer enriched water into oil and manipulating its shape by applying an electric field. The shape remains intact after cease of the forcing. <br /> "Russell (...) points out that the advance holds promise for a wide range of different applications including in drug delivery, biosensing, fluidics, photovoltaics, encapsulation and bicontinuous media for energy applications and separations media."

nice concept - still have to look closer into it ...

remember that I wanted to do this at a University lab course! ...LS

mah...

of interest? -LS

The first complete theory of how plasmons produce "hot carriers" has been developed by researchers in the US. The new model could help make this process of producing carriers more efficient, which would be good news for enhancing solar-energy conversion in photovoltaic devices.

I did not read the paper but what is further down written in the article, does not give much hope that this actually gives much more insight than what we had nor that it could be used in any way to improve current PV cells soon: e.g. "To fully exploit these carriers for such applications, researchers need to understand the physical processes behind plasmon-induced hot-carrier generation. Nordlander's team has now developed a simple model that describes how plasmons produce hot carriers in spherical silver nanoparticles and nanoshells. The model describes the conduction electrons in the metal as free particles and then analyses how plasmons excite hot carriers using Fermi's golden rule - a way to calculate how a quantum system transitions from one state into another following a perturbation. The model allows the researchers to calculate how many hot carriers are produced as a function of the light frequency used to excite the metal, as well as the rate at which they are produced. The spectral profile obtained is, to all intents and purposes, the "plasmonic spectrum" of the material. Particle size and hot-carrier lifetimes "Our analyses reveal that particle size and hot-carrier lifetimes are central for determining both the production rate and the energies of the hot carriers," says Nordlander. "Larger particles and shorter lifetimes produce more carriers with lower energies and smaller particles produce fewer carriers, but with higher energies."