Solar cells. Existing solar cell technologies, based on semiconductor materials, involve high material costs. Consequently, although sunlight is free, the overall cost of solar power (amortized over the lifetime of the cell, typically 20 years) is around ten times higher than the cost of electricity generated by burning fossil fuels. Semiconductor-based cells have the highest efficiency, but there is little that can be done to either increase the efficiency or reduce the manufacturing cost. To produce solar cells with lower efficiencies (e.g. 10% instead of 15-20%) and are cheaper to manufacture, STMicroelectronics, Catania, Italy, is following two approaches. One of these, invented in 1990 by Professor Michael Graetzel of the Swiss Federal Institute of Technology, uses a similar principle to photosynthesis. Known as the Dye-Sensitized Solar Cell (DSSC), the cell uses an organic dye to absorb the light and create electron-hole pairs, a nanoporous metal oxide layer to transport the electrons, and a hole-transporting material, which is typically a liquid electrolyte. The ST team is also developing low cost solar cells using a full organic approach, in which a mixture of electron-acceptor and electron-donor organic materials is sandwiched between two electrodes. The nanostructure of this blend is crucial for the cell performance because the electron-donor and electron-acceptor materials have to be in intimate contact at distances below 10 nm. ST plans to use Fullerene as the electron-acceptor material and an organic copper compound as the electron-donor.
Hot air. Proe Power Systems, Thousand Oaks, CA, announced in November that it received a Notice of Patent Claims Allowance from the U.S. Patent and Trademark Office for HRPG heat recovery power generator technology. To date, DOE cogeneration requirements have been met by using engine exhaust heat to generate steam (to drive a steam engine for additional power) and/or to heat water. In contrast, Proe Power Systems’ “dry” HRPG technology uses air instead of water or steam. An existing internal combustion powerplant can be easily modified by connecting the internal combustion engine exhaust into the HRPG heat exchanger and then coupling the drive shafts of the HRPG engine and the existing internal combustion engine. The linked engines require no additional controls and the internal combustion exhaust heat then drives the HRPG engine to produce 15% to 25% by simply exhausting it into a building directly or through the building’s existing hot air ducts.
Green labeling. Korea, Taiwan, Japan, and even Poland now all have their own
different green label requirements, according to a newly updated report, Green Labeling: Global Guide for Marketers in the New Millennium 2003 Edition, from Raymond Communications, College Park, MD. “Our research indicates that about 15 European and Eastern European countries now have some sort of mandatory green label requirements, though most accept some version of the SPI code with chasing arrows,” says Michele Raymond, who also publishes Recycling Laws International. Poland adopted regulations requiring use of a round arrow symbol for some “recyclable” packages that no one else uses — the symbol was proposed at the European Commission but abandoned five years ago. South Korea now requires a different triangle, with the words “Separate, please” in Korean, while Japan requires a different set of symbols that include Japanese characters. The report covers voluntary and mandatory green labeling regulations for the U.S. and 20 other countries. Besides mandatory measures in Europe and Asia, it also summarizes all the major voluntary ecolabel programs, covering 22 countries.
Hydrogen from methane. Scientists at the Federal Institute of Technology (EPFL), Lausanne, Switzerland, have demonstrated a key mechanism in the process used to produce hydrogen from methane. Published in the Oct 3rd issue of Science, the study was an outgrowth of research into steam reforming, where methane is made to react with water on a nickel surface heated to 1000°C. The essential step is the adhesion of methane molecules to the nickel. The EPFL scientists investigated this phenomenon by using a laser to energize methane molecules before they reached the nickel surface, and were able to show the probability of adherence was dependant on the type of vibrational motion of the molecule. The discovery may lead to new approaches in producing hydrogen more efficiently.
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Solar cells. Existing solar cell technologies, based on semiconductor materials, involve high material costs. Consequently, although sunlight is free, the overall cost of solar power (amortized over the lifetime of the cell, typically 20 years) is around ten times higher than the cost of electricity generated by burning fossil fuels. Semiconductor-based cells have the highest efficiency, but there is little that can be done to either increase the efficiency or reduce the manufacturing cost. To produce solar cells with lower efficiencies (e.g. 10% instead of 15-20%) and are cheaper to manufacture, STMicroelectronics, Catania, Italy, is following two approaches. One of these, invented in 1990 by Professor Michael Graetzel of the Swiss Federal Institute of Technology, uses a similar principle to photosynthesis. Known as the Dye-Sensitized Solar Cell (DSSC), the cell uses an organic dye to absorb the light and create electron-hole pairs, a nanoporous metal oxide layer to transport the electrons, and a hole-transporting material, which is typically a liquid electrolyte. The ST team is also developing low cost solar cells using a full organic approach, in which a mixture of electron-acceptor and electron-donor organic materials is sandwiched between two electrodes. The nanostructure of this blend is crucial for the cell performance because the electron-donor and electron-acceptor materials have to be in intimate contact at distances below 10 nm. ST plans to use Fullerene as the electron-acceptor material and an organic copper compound as the electron-donor. 
different green label requirements, according to a newly updated report, Green Labeling: Global Guide for Marketers in the New Millennium 2003 Edition, from Raymond Communications, College Park, MD. “Our research indicates that about 15 European and Eastern European countries now have some sort of mandatory green label requirements, though most accept some version of the SPI code with chasing arrows,” says Michele Raymond, who also publishes Recycling Laws International. Poland adopted regulations requiring use of a round arrow symbol for some “recyclable” packages that no one else uses — the symbol was proposed at the European Commission but abandoned five years ago. South Korea now requires a different triangle, with the words “Separate, please” in Korean, while Japan requires a different set of symbols that include Japanese characters. The report covers voluntary and mandatory green labeling regulations for the U.S. and 20 other countries. Besides mandatory measures in Europe and Asia, it also summarizes all the major voluntary ecolabel programs, covering 22 countries.