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Despite shifting into higher gear within the consumer's green conscience, hybrid vehicles are still tethered to the gas pump via a fuel-thirsty 100-year-old invention: the internal combustion engine. However, researchers at Michigan State University have built a prototype gasoline engine that requires no transmission, crankshaft, pistons, valves, fuel compression, cooling systems or fluids. Their so-called Wave Disk Generator could greatly improve the efficiency of gas-electric hybrid automobiles and potentially decrease auto emissions up to 90 percent when compared with conventional combustion engines. The engine has a rotor that's equipped with wave-like channels that trap and mix oxygen and fuel as the rotor spins. These central inlets are blocked off, building pressure within the chamber, causing a shock wave that ignites the compressed air and fuel to transmit energy. The Wave Disk Generator uses 60 percent of its fuel for propulsion; standard car engines use just 15 percent. As a result, the generator is 3.5 times more fuel efficient than typical combustion engines. Researchers estimate the new model could shave almost 1,000 pounds off a car's weight currently taken up by conventional engine systems. Last week, the prototype was presented to the energy division of the Advanced Research Projects Agency, which is backing the Michigan State University Engine Research Laboratory with $2.5 million in funding. Michigan State's team of engineers hope to have a car-sized 25-kilowatt version of the prototype ready by the end of the year.

ScienceDaily (June 18, 2010) - Conventional solar cell efficiency could be increased from the current limit of 30 percent to more than 60 percent, suggests new research on semiconductor nanocrystals, or quantum dots, led by chemist Xiaoyang Zhu at The University of Texas at Austin.

In a paper published in Nature Photonics, University of Toronto researchers report the first efficient two-layer solar cell based on colloidal quantum dots (CQD) to capture both visible and near-infrared rays. CQDs are nanoscale materials that can be tuned to respond to specific wavelengths of the visible and invisible spectrum. By capturing such a broad range of light waves - wider than normal solar cells - tandem CQD solar cells can in principle reach up to 42 per cent efficiencies. The best single-junction solar cells are constrained to a maximum of 31 per cent efficiency. (In reality, solar cells that are on the roofs of houses and in consumer products have 14 to 18 per cent efficiency.) The researchers expect that in five years, solar cells using the graded recombination layer paper will be integrated into building materials and mobile devices.

Cisco predicts more than 15 billion network-connected devices by 2015, reaching 966 exabytes (10^18 bytes) per year - close to 1 zettabyte (10^21 bytes). Average global IP traffic in 2015 will reach 245 terabytes per second, equivalent to 200 million people streaming an HD movie (1.2 Mbps) simultaneously. This growth will primarily be driven by the global online video community, which will increase by approximately 500 million users by 2015, up from more than 1 billion Internet video users in 2010, Cisco says. Global IP traffic growth is driven by four primary factors, according to Cisco: An increasing number of devices: The proliferation of tablets, mobile phones, connected appliances and other smart machines is driving up the demand for connectivity.  By 2015, there will be nearly 15 billion network connections via devices - including machine-to-machine - and more than two connections for each person on earth. More Internet users: By 2015, there will be nearly 3 billion Internet users - more than 40 percent of the world's projected population. Faster broadband speed: The average fixed broadband speed is expected to increase four-fold, from 7 megabits per second in 2010 to 28 Mbps in 2015. The average broadband speed has already doubled within the past year from 3.5 Mbps to 7 Mbps. More video: By 2015, 1 million video minutes -+ the equivalent of 674 days - will traverse the Internet every second. By 2015, the Asia Pacific region will generate the most IP traffic (24.1 exabytes per month), surpassing last year's leader, North America (22.3 exabytes per month), for the top spot. The fastest-growing IP-traffic regions for the forecast period (2010-2015) are the Middle East and Africa, surpassing last year's leader, Latin America.

Duke University engineer Nico Hotz has proposed a hybrid solar system in which sunlight heats a combination of water and methanol in a maze of tubes on a rooftop to produce hydrogen. The device is a series of copper tubes coated with a thin layer of aluminum and aluminum oxide and partly filled with catalytic nanoparticles. A combination of water and methanol flows through the tubes, which are sealed in a vacuum. Once the evaporated liquid achieves higher temperatures, tiny amounts of a catalyst are added, which produces hydrogen. This combination of high temperature and added catalysts produces hydrogen very efficiently, Hotz said. The resulting hydrogen can then be immediately directed to a fuel cell to provide electricity to a building during the day, or compressed and stored in a tank to provide power later. After two catalytic reactions, the system produced hydrogen much more efficiently than current technology without significant impurities, Hotz said. The resulting hydrogen can be stored and used on demand in fuel cells. "This set-up allows up to 95 percent of the sunlight to be absorbed with very little being lost as heat to the surroundings," he said. "This is crucial because it permits us to achieve temperatures of well over 200 degrees Celsius within the tubes. By comparison, a standard solar collector can only heat water between 60 and 70 degrees Celsius." Holtz performed a cost analysis, comparing a standard photovoltaic cell, a photocatalytic system, and the hybrid solar-methanol system.  He found that the hybrid system is the least expensive solution, with a total installation cost of $7,900 if designed to fulfill the requirements in summer. The paper describing the results of Hotz's analysis was named the top paper during the ASME Energy Sustainability Fuel Cell 2011 conference in Washington, D.C. Topics: Energy | Nanotech/Materials Science