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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.

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.

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

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.

MIT researchers have developed a new application of carbon nanotubes that shows promise as an innovative approach to storing solar energy for use whenever it's needed. Storing the sun's heat in chemical form - rather than first converting it to electricity or storing the heat itself in a heavily insulated container - has significant advantages: in principle, the chemical material can be stored for long periods of time without losing any of its stored energy. The researchers created carbon nanotubes in combination with a compound called azobenzene. The resulting molecules, produced using nanoscale templates to shape and constrain their physical structure, and the concept that can be applied to many new materials. This material is vastly more efficient at storing energy in a given amount of space - about 10,000 times higher in volumetric energy density, making its energy density comparable to lithium-ion batteries, the researchers said. Ref.: Alexie M. Kolpak, Jeffrey C. Grossman, Azobenzene-Functionalized Carbon Nanotubes As High-Energy Density Solar Thermal Fuels, Nano Letters, 2011; 110705085331088 [DOI: 10.1021/nl201357n]

ScienceDaily (June 26, 2011) - In a paper published in Nature Photonics, U of T Engineering researchers report a new solar cell that may pave the way to inexpensive coatings that efficiently convert the sun's rays to electricity.

ScienceDaily (July 5, 2011) - Future computers may rely on magnetic microprocessors that consume the least amount of energy allowed by the laws of physics, according to an analysis by University of California, Berkeley, electrical engineers.

Automotive Fuel Injection Systems Market is projected to raise by 2023, growing at a CAGR of over 6% owing to increasing vehicle production, growing demand for better fuel efficiency & power output, and stringent exhaust emissions.

UAE Cloud Storage Market is expected to grow at a double digit CAGR during 2014-2024. Due to growing need for improved efficiency, growing inclination towards organizing cloud-based solutions.

Mobile Apps and mobility are highly influencing in online grocery delivery businesses. Know how Mobile Application Management feature of an MDM Solution is allowing grocery delivery to be prompt, efficient and productive services.

A whitepaper and a guide to know how MDM software plays a significant role in empowering and enabling frontline workers, accelerating productivity and efficiency.

Unified Communications integrated Mobile Device Management streamlines Enterprise mobility, workforce productivity and operational efficiency. Know how Scalefusion is simplifying business communication and operations.

mHealth or mobility in healthcare transforming healthcare aiding smart and efficient patient reach and services. Know the future of mHealth and technology like Mobile Device Management for healthcare is redefining and driving mobility in healthcare.

Increase your work efficiency using virtual meeting solutions into your business. They help businesses to yield great results and eliminate the need of physical meetings. Virtual meetings can allow teams to meet together while being as spread out as the business demands them to be and save great sums of traveling cost. Companies are able to call meetings as issues come up that need to be addressed quickly. They are a great way to demonstrate a product or service to a client without having to spend time traveling to the client. If time is money, then using virtual meetings to save time will help any business save money.