Energy Harvesting
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Award-winning device harvests energy from railway track vibrations
Much of the abundant mechanical energy around us is irregular and oscillatory and can be somewhat difficult to efficiently tap into. Typical energy harvesting systems tend to be built for low power applications in the milliwatts range but researchers from New York's Stony Brook University have developed a new patent-pending electromagnetic energy harvester capable of harnessing the vibrations of a locomotive thundering down a stretch of track to power signal lights, structural monitoring systems or even track switches. As a train rolls down the track, the load it exerts on the track causes vertical deflection. This displacement could engage a regenerative device like an electromagnetic harvester and generate enough power to operate local railway applications, which is especially useful in remote areas where electrification is not cost effective.
Approximately 90 percent of the world’s electricity is generated by heat energy. Unfortunately, electricity generation systems operate at around 30 to 40 percent efficiency, meaning around two thirds of the energy input is lost as waste heat. Despite this, the inefficiency of current thermoelectric materials that can convert waste heat to electricity has meant their commercial use has been limited.
World’s most efficient thermoelectric material developed
Austrian algae biofuel-production technology to debut in Brazil
The state of Pernambuco in Brazil’s northeast is going to become home to the country’s first algal biomass plant, thanks to an agreement between See Algae Technology (SAT), an Austrian developer of equipment for the commercial production of algae, and JB, one of Brazil’s leading ethanol producers. The plant will produce algal biomass from natural and genetically modified strains of algae. So far, the cost of producing algae has been the biggest obstacle to bringing algae-based fuel to the market, but SAT has introduced a technology that has brought the price down to about that of ethanol - R$0.80 to $1.00 (US$0.40 - $0.50) per liter (around one quarter of a gallon).Chemical reaction eats up CO2 to produce energy ... and other useful stuff
Transmission electron microscopy image of carbon nitride created by the reaction of carbon dioxide and Li3N While there are plenty of ways to make carbon-based products from CO 2 , these methods usually require a lot of energy because the CO 2 molecules are so stable. If the energy comes from the burning of fossil fuels, then the net result will be more CO 2 entering the atmosphere. Now a material scientist at Michigan Technological University has discovered a chemical reaction that not only soaks up CO 2 , but also produces useful chemicals along with significant amounts of energy.
Virtually all electrical devices and industrial processes create heat as they operate, which is typically wasted. In the past several years, various thermoelectric technologies have been developed to address that situation, by converting such heat into electricity . The ideal material for the purpose would be one that has a high electrical conductivity, but a low thermal conductivity - that way, it could carry plenty of electricity without losing efficiency through overheating. Unfortunately, electrical and thermal conductivity usually seem to go hand in hand. With some help from an ordinary microwave oven, however, researchers from New York's Rensselaer Polytechnic Institute have created a nanomaterial that appears to fit the bill.
New heat-harvesting material made in $40 microwave oven
