Researchers at Stanford have announced a new class of solar collectors – they’re calling them “photon enhanced thermionic emission” devices.  They’re claiming up to 60% conversion efficiency (theoretically) with fairly standard manufacturing process, but the real benefit is that they can operate at extremely high temperatures.

Regular PV becomes less effective as the temperature increases, making it difficult to do anything with the waste heat generated.  By using this new type of energy conversion, the collecting plate can be kept at high temperatures, providing high-temp ‘waste’ heat, which can then be used for different types of energy storage.  Generally, the bigger the temperature difference between your source (the sun) and sink (the atmosphere), the more efficient energy conversion processes are.

The article doesn’t go into much detail, but guess from the name (specifically the thermionic emission part) I’m guessing these things work similar to how light bulbs work, but in reverse.

I’ve seen similar claims in the news before, but I thought I’d post this one.  According to Live Science, researchers here at UT Austin have developed a spray on PV system using nanoparticle CIGS.  They’re still working on the details – they currently only get 1% efficiency, but if they can work out the details this could be an interesting product.

via Inhabitat

The Obama Administration will lend Tesla Motors $465 million to build an electric sedan and the battery packs needed to propel it. It’s one of three loans totaling almost $8 billion that the Department of Energy awarded today to spur the development of fuel-efficient vehicles.

Energy Secretary Steven Chu announced that the Department of Energy is also lending $5.9 billion to Ford to retool factories in five states. Nissan will receive $1.6 billion to refurbish a factory in Tennessee to produce electric cars. The loans are the first awarded under the $25 billion Advanced Technology Vehicle Manufacturing Program to help automakers offset the cost of retooling to build eco-friendlier cars that are at least 25 percent more fuel-efficient than 2005 models.

via Wired

OK, so this sounds like something out of bizarro-world, but as far as I can tell it’s not a late April Fools joke:

Microscopic algae called diatoms could help triple the electrical output of experimental, dye-sensitized solar cells, according to researchers at Oregon State University and Portland State University.

Dye-sensitized solar cells are favored as a thin-film material because they work in low-light conditions and are fabricated with environmentally benign materials compared to silicon solar cells. However, silicon cells have more than twice the efficiency, as much as 20 percent compared to less than 10 percent for dye-sensitized solar cells.

The Oregon engineers fed titanium dioxide to living diatoms so they would build shells from the photovoltaic material instead of silicon dioxide, from which they usually build their shells.

“We have found that diatoms will readily accept titanium dioxide in place of silicon dioxide if that’s all we make available to them,” said Rorrer.

The engineers have grown diatoms on a substrate. They have also bred them in bulk, then coated a glass surface with the material. In either case, the pattern of intricate nanoscale features both boosted the photovoltaic surface area available and trapped incident light inside the pores.

After removing the organic material from the shells, leaving behind the diatom’s nanoscale skeletons composed of titanium dioxide, the researchers mixed the material in a dye. The resulting thin-film solar cells had three times the efficiency, according to Rorrer, than the same thin films without diatom nanoscale patterning.

I want a set of titanium-algae-skeleton solar arrays!

Boingboing just posted a review of a book called ‘Sustainable Energy’ which is available in full as a PDF here.  So far I love it.  From the original review:

This is to energy and climate what Freakonomics is to economics: an accessible, meaty, by-the-numbers look at the physics and practicalities of energy. MacKay, a Cambridge Physics prof, approaches the subject of carbon and sustainability with a scientific, numeric eye. First, in a section called “Numbers, not adjectives,” he looks at all the energy and carbon inputs and outputs in Britain and the rest of the world: this is how many kWh of energy are needed to power all of Britain’s vehicles. This is how many kWh you would get if you covered the entire British shore with windmills, or wave-farms. This is Britain’s geothermal potential. Here’s how much carbon vegetarianism offsets. Here’s how much carbon unplugging your idle appliances saves (0.25%, making the campaign to switch off energy vampires into a largely pointless exercise — as MacKay says, “If everyone does a little bit, we’ll get a little bit done”). This is the carbon-footprint of all of Britain’s imports, gadgets, office towers, and so on.

Popular Science has a story about the recent announcement that PV prices have dropped below $1/W, along with an anaylsis of material availability suggesting that these prices couldn’t keep pace with large-scale production:

First Solar’s eventual goal is “grid parity,” a phrase that refers to making solar power cost the same as competing conventional power sources without subsidies. Right now the cost of making panels accounts for a little less than half the total cost of installation. The company estimates that it needs to get manufacturing costs down to $0.65 to $0.70 per watt, and other installation costs down to $1 a watt in order to reach grid parity—goals First Solar plans to reach by 2012.

The question, though, is whether First Solar or any other solar manufacturer would be able to handle the flood of orders that would ensue if they reached competitive cost. At that point, it comes down to a matter of having enough of raw materials. That is where the real limitations come to bear, according to a paper that will appear in the March issue of the journal Environmental Science & Technology. In the paper, Wadia and colleagues Paul Alivisatos and Daniel Kammen evaluated the global supplies and extraction costs for 23 promising photovoltaic semiconductor materials and found that the three materials that currently dominate the market—silicon, CdTe and another thin-film technology based on copper indium gallium selenide (CIGS)—all have limitations when ordered in mass. While silicon is the second-most abundant element in the Earth’s crust, it requires enormous amounts of energy to convert into a usable crystalline form. This is a fundamental thermodynamic barrier that will keep silicon costs comparatively high. Both CIGS and First Solar’s CdTe rank poorly in abundance and extraction cost, with CdTe ranking dead last in long-term potential based on current annual extraction rates.

…

To that end, Wadia and his colleagues found that iron pyrite—better known as fool’s gold—was several orders of magnitude better than any of the alternatives, based on both cost and abundance. Copper sulfide and copper oxide were also attractive candidates. The problem with these materials is that they’re less efficient in converting the sun’s rays to electricity, and as a result have been the focus of considerably less research. But the Berkeley study accounts for this fact, and concludes that lower-efficiency materials that are cheaper and more abundant will ultimately serve the alternative energy market better.

from Tech Review:

The acrylic component–called a Light-Guide Solar Optic (LSO)–is a new type of solar concentrator that could significantly lower the cost of generating electricity from the sun. Unlike existing designs, there’s no need for mirrors, complex optics, or chemicals to trap and manipulate the light. “It’s pure geometric optics,” says Morgan, director of business development at Toronto-based Morgan Solar.

From what I can tell from their website, it probably works by using a diffraction grating made from a material with a low IOR on top of a sheet of material with a higher IOR – the grating would deflect the light towards the center, and when the light crossed the boundary from one material to another the light angle is reduced sufficiently to be trapped in the second material through internal reflection.

Just a guess though…