Renewables, fuel cells, hydrogen, and efficiency
Tuesday, March 01, 2005
Nano for better batteries, fuel cells: SRI scientist "Narang and other researchers have found ways to combine high energy density with high power using nanotechnology. In SRI’s case, the approach involves using high aspect ratio nanomaterials, or nanofibers. The nanofibers are minutely small in one dimension (about 20 nanometers) so energy flows rapidly across them. But because they are, relatively speaking, long in the other dimension (50 to 200 nanometers) they can store much more energy than nanoparticles with small dimensions all around. The result, Narang maintains, is a battery that can deliver about eight times the power of a traditional battery while providing comparable energy. Plus, there’s a bonus: The nanoscale dimensions that let energy move rapidly also allow the battery to recharge faster when the energy flow is reversed, a feature that’s important for hybrid cars designed to harvest energy from braking and use it to recharge the batteries.
Other organizations are working on the same problem. Ener1, of Fort Lauderdale, Fla., is researching enhancements for electrolytes and cathodes, using nano-structured powders for electrolytes and nano-structured, iron-disulfide for cathodes. The company says that by combining its nano-structured, iron-disulfide cathode with its polymer electrolyte it can provide high energy and a long cycle life. ..
Batteries, however, are not the only nano-enhanced technology poised to augment alternative energy efforts. .. California-based Proton Power proposes using solid acid fuel cells to supplement diesel engines inside long-haul trucks. Currently, truckers idle their engines when resting to power heating, air conditioning and other amenities. Proton Power would provide a supplemental fuel cell that truckers could use when not driving. .. “The thinner the electrolyte layer,” [Proton's founder Calum] Chisolm said, “the more power.” Currently funded by friends and family, the California Institute of Technology spinout is looking at longer-term financing opportunities and broad markets. ..
SRI is working on a form of solid oxide fuel cell that would use military-grade diesel fuel. The design takes advantage of nanostructures for catalysts and uses 200-nanometer powders for a thin electrolyte, upping the power in the same manner as Chisolm’s solid acid cell." 9:43:34 AM
Nanotech Startups Eye Solar Energy Spotlight: A short article from Investor's Business Daily in November 2004 spotlighted a few companies with comments from analysts: "At least three startups -- Nanosolar, Nanosys and Konarka Technologies -- are using nanotech to try to make solar energy more viable. In time, such work could become "world changing," said Josh Wolfe, a managing partner of nanotech-focused investment firm Lux Capital in New York. Lux has invested in Nanosys. "All three of these firms have a different approach, but all of them are trying to create solar energy anywhere, any time," Wolfe said.
Nanotech solar cells could come down to fossil-fuel prices within a few years, says Steven Milunovich, an analyst with Merrill Lynch. Electricity now costs 7 cents per kilowatt-hour in the U.S. and 19 cents in Japan. Solar cells run about 43 cents. "There could be significant adoption" if nanotech solar drops below 7 cents, said Milunovich in a recent research note. Nanotech could have "a significant impact" on the $3 billion-plus solar power market. "Cheaper manufacturing plants and processes could make solar competitive with fossil fuels," he wrote.
Nanosolar, based in Palo Alto, Calif., is building nanotech panels that are 100 times thinner than current solar panels. This approach could let the firm mass-produce cheaper solar cells by printing them out like rolls of newspaper. .. Nanosolar plans to make test products next year and go to full production the following year. ..
Nanosys, also based in Palo Alto, has partnered with Japanese corporate giant Matsushita (NYSE:MC - News) to make nano materials into special shapes known as tetrapods. This material is laid onto plastic substrates that are produced like photo film to make nanopanels that are more flexible and smaller than current rooftop solar panels. By encasing such solar panels between windowpanes, skyscrapers might someday double as self-contained power plants..
Konarka of Lowell, Mass., is developing plastic sheets that are embedded with titanium oxide nanocrystals. The crystals are coated with light-absorbing dyes." 9:24:35 AM
Nanosponge for hydrogen:
"The materials made by Xuebo Zhao and colleagues are composed of long carbon chains linked by metal atoms. When they are crystallized, these molecules frame cavities less than a nanometer across, connected by windows that are even smaller than a hydrogen molecule. While the cavities are being filled, hydrogen can wriggle through these windows because the carbon chains are flexible.
But once the cavities fill, the chains lose their room to flex, forcing the windows closed. As a result, the material can be loaded with hydrogen gas at high pressure, but does not release the gas when pressures drop to normal, essentially forming a molecule-sized pressure seal. " 8:24:01 AM