Hitting the Theoretical Roof of Converting Waste Heat to Electricity

The need to get rid of excess heat creates a major source of inefficiency in everything from computer processor chips to car engines. According to Peter Hagelstein, an associate professor of Electrical Engineering at MIT, existing solid-state devices to convert heat into electricity are not very efficient. Experimenting with thermal diodes, an MIT team has come closer to the theoretical limitations for the efficiency of such a conversion.

Posted in: GDM, News, News, Energy, Energy Efficiency, Thermoelectrics, Transportation


Microscopic Bubbles Clean Oil from Polluted Water

Small amounts of oil leave a fluorescent sheen on polluted water. Oil sheen is hard to remove, even when the water is aerated with ozone or filtered through sand. A University of Utah engineer has developed an inexpensive method to remove oil sheen by repeatedly pressurizing and depressurizing ozone gas - creating tiny bubbles that attack the oil so it can be removed by sand filters.

Posted in: GDM, News, News, Green Design & Manufacturing, Remediation Technologies


Are space elevators a viable concept?

This week’s question concerns space elevators. Last week, during NASA’s Space Elevator Games in the Mojave Desert, a robot powered by a ground-based laser beam scampered up a 2,953 foot cable suspended from a helicopter hovering almost a mile overhead. The trip took just over four minutes. The achievement, some say, brings us one step closer to making the concept of space elevators a reality. For those not familiar with the concept, a space elevator would consist of an electrically powered vehicle that can travel up and down a cable that is anchored to Earth and suspended from a mass placed in geosynchronous orbit thousands of miles above the Earth. Power for the elevator would be provided by ground-based lasers aimed at photovoltaic cells mounted on the underside of the vehicle. Although it may sound fanciful, proponents of the theory believe that, with certain technological advances, it’s completely feasible. What do you think? Are space elevators a viable concept?

Posted in: Question of the Week


Algae as a High-Temperature Hydrogen Source

A team of researchers from the University of Tennessee, Knoxville and Oak Ridge National Laboratory have found that the inner machinery of photosynthesis can be isolated from certain algae and, when coupled with a platinum catalyst, is able to produce a steady supply of hydrogen when exposed to light.

Posted in: GDM, News, News, Biomass, Energy, Energy Efficiency, Energy Storage, Renewable Energy, Solar Power, Alternative Fuels, Green Design & Manufacturing


Japan Wins Australia's Global Green Challenge

The "Tokai Challenger" solar car from Japan's Tokai University won the 3,000 kilometer Global Green Challenge race down the center of Australia. The Tokai Challenger maintained an average speed of over 100 kilometers per hour, or about 62 miles per hour, besting the winner of the previous four races - the Dutch Nuon Solar Team.

Posted in: GDM, News, News, Batteries, Electronics & Computers, Energy, Renewable Energy, Solar Power, Alternative Fuels, Green Design & Manufacturing, Transportation


EPA's National TV Recycling Challenge

Electronic Manufacturers Recycling Management Company (MRM) is the winner of EPA's National TV Recycling Challenge. MRM developed a TV collection network that uses a variety of collection approaches, including establishing collection points with charities and self-storage units, to recycle approximately 3 million pounds of TVs.

Posted in: GDM, News, News, Green Design & Manufacturing, Recycling Technologies


Three-Dimensional, Hidden Solar Cell

Using zinc oxide nanostructures grown on optical fibers and coated with dye-sensitized solar cell materials, researchers at the Georgia Institute of Technology have developed a new type of three-dimensional photovoltaic system. The approach could allow PV systems to be hidden from view and located away from traditional locations such as rooftops.

Posted in: GDM, News, News, Energy, Energy Efficiency, Energy Storage, Renewable Energy, Solar Power


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