Solar Impulse, the group whose goal is to fly an airplane around the world propelled solely by solar energy, has proven that night flight using solar energy stored in batteries in possible.

On July 7, 2010, just before 7 in the morning, the prototype Solar Impulse HB-SIA took off from Payerne military airfield for a memorable flight.

André Borschberg piloted the solar-powered aircraft with a wingspan of 64 meters on a non-stop flight lasting more than 26 hours. In the night of July 7-8, the Solar Impulse flew using solar energy stored in the batteries in the course of the day.

It was intended to be the longest and highest flight in the history of solar-powered aviation: the FAI (Fédération Aéronautique Internationale) immediately awarded the Solar Impulse three new world records in the Solar Powered Airplane class. Based on the technical organization and adjudication by the Swiss Aero Club, the FAI ratified the following flight records, owned by André Borschberg:

- Absolute height: 9235 m

- Height gain: 8744 m

- Duration: 26 hours, 10 minutes, 19 seconds

Visit a 3-D animation that explores the Solar Impulse plane inside and out at http://www.solarimpulse.com/index.php.

The Maryland team developed the smart alloy at the Keck Laboratory for Combinatorial Nanosynthesis and Multiscale Characterization and is now ready to test a prototype.

Researchers at the University of Maryland are developing a new “thermally elastic” metal alloy for use in advanced refrigeration and air conditioning systems. The technology promises far greater efficiency and reductions in greenhouse gas emissions.

The Maryland team will soon begin testing of a prototype system, with economic stimulus funding from the U.S. Department of Energy. The new grant is part of a program designed to bring “game-changing” technologies to market.

“Air conditioning represents the largest share of home electric bills in the summer, so this new technology could have significant consumer impact, as well as an important environmental benefit,” says Eric Wachsman, director of the University of Maryland Energy Research Center (UMERC).

“The approach is expected to increase cooling efficiency 175 percent, reduce U.S. carbon dioxide emissions by 250 million metric tons per year, and replace liquid refrigerants that can cause environmental degradation in their own right,” Wachsman adds.

The lead researchers on the project, Ichiro Takeuchi, Manfred Wuttig and Jun Cui, materials science engineers in Maryland’s A. James Clark School of Engineering, have developed a solid coolant to take the place of fluids used in conventional refrigeration and air conditioning compressors. Their system represents a fundamental technological advance, they say.

In the next phase of research, the team will now test the commercial viability of their smart metal for space cooling applications. The 0.01-ton prototype is intended to replace conventional vapor compression cooling technology. Instead of fluids, it uses a solid-state material – their thermoelastic shape memory alloy.

This two-state alloy alternately absorbs or creates heat in much the same way as a compressor-based system, but uses far less energy, the Maryland team explains. Also, it has a smaller operational footprint than conventional technology, and avoids the use of fluids with high global warming potential.

General Electric Global Research and the Pacific Northwest National Laboratory are partnering with the University of Maryland on the project.

The Department of Energy has given the team $500,000 – one of only 43 grants nationwide – as part of its Advanced Research Projects Agency-Energy (ARPA-E) program, designed to advance out-of-the-box, transformational research from the laboratory to marketplace. The grants are funded with money from the federal American Recovery and Reinvestment Act.

“These grants are highly competitive and require a demonstration that the technology has genuine commercial potential,” Wachsman explains. “This represents a significant investment in the state of Maryland and the development of its ‘green’ economy.”

Wachsman, who has been on the job at Maryland for about eight months, is working to make UMERC the campus focal point of interdisciplinary energy research.

He’s also submitted a proposal to the Department of Energy to locate a $130 million multi-institutional research hub in the Washington, D.C. region, focusing on a broad array of green building research (including including technology such as this). The agency is expected to make a decision next month on the highly competitive grant.

The grant to develop Maryland’s solid-state coolant is part of a $92 million package of ARPA-E awards distributed to 18 states.

The ARPA-E program stems from a recommendation contained in the 2006 National Academies report, Rising Above the Gathering Storm – a report co-authored by University of Maryland President C.D. Mote, Jr.

Designed to spur U.S. innovation, the program was established in the 2007 America Competes Act.

Click here to view the embedded video.

The new glass innovation comes just a few weeks after the company announced more than $100 million in Department of Energy (DOE) loan guarantees and government tax credits, spurred on by the Department of Energy’s Loan Guarantee Program which was established under the Energy Policy Act of 2005.

The Sage plant is filled with natural light.

Combining unprecedented energy savings with breakthrough improvements in occupant comfort sets a new standard for high performance architectural windows, says SAGE CEO and Founder, John Van Dine. “In addition to reducing energy usage and making the space more comfortable, productive and enjoyable, we can eliminate costly building features such as mechanized shades and blinds, and exterior add-ons like sunshades. Our windows can also contribute to LEED building credits, and decrease HVAC system size. This not only reduces the natural resources and energy consumed in the construction process, it also decreases the building owner’s investment in the building, making SAGE’s dynamic glazing product a low-cost sun management solution as well.”

Tests show the dynamic, triple-glazed glass has an insulating R-value higher than 8, compared to an R-3 value typical of most low-E double pane glass. Combining super insulation with the glazing’s dynamic tinting capability provides a 16% energy improvement over state-of-the-art static triple pane glass with low-E, and better than a 50% improvement over single pane glazings. This makes the product an ideal solution for new construction and retrofit primarily in heating-dominated climates where high R-value glazings are needed.

SAGE’s dynamic tinting technology uses nanotechnology to produce its glazing, which people can change electronically to manage daylight, as if they were controlling the way transition lenses in sunglasses work. The technology saves building energy by managing natural daylight and solar heat gain, while enhancing occupant comfort and well-being by eliminating glare.

Tom Paladino, founder and president of Paladino and Company, a pioneer and leader in the sustainable/green building movement, says that a highly insulating, dynamic window would be an important addition to the nation’s portfolio of sustainable building technologies. “It is very exciting to see the commercialization of a building product as energy efficient as the high R-value window,” Paladino said. “The combination of variable tinting and triple-glazed construction will result in a product with superior thermal properties that can contribute to dramatic reductions in both passive energy usage and peak cooling load.”

The trend toward building designs that incorporate the extensive use of glass continues to grow because people want a view and connection to the outside world. The energy inefficiency of glass, however, has historically challenged architects and builders who seek to create sustainable designs. Moreover, once in the space, occupants usually find that the view they so desired is the source of intolerable glare and heat. They pull the blinds and close off their view, negating the very purpose of the window.

“The only reason windows are put into buildings is for the people inside,” Van Dine added. “The dynamic, triple-pane glass enables building owners to optimize the comfort and productivity of the occupants as well as the energy performance of the building. It’s the best of both worlds.”

SAGE has shipped its first dynamic, triple-pane product, joining a product line of dynamic, double-pane glass that has been on the market since 2004 with hundreds of installations worldwide.

Originally published February 2007

A switchable mirror material developed by scientists at the National Institute of Advance Industrial Science and Technology could be used for windows in buildings or automobiles and could reduce the energy consumed by air conditioners by more than 30%.

Mirror state

The new material uses a thin film of magnesium-titanium alloy in a 60-cm-by-70-cm mirror window that can switch from reflective to transparent states. The switchable windows use the thin film as a coating on the inner sides of two panes of glass. Switching is achieved by introducing a gas that contains hydrogen at a low concentration of about 1% or oxygen at a concentration of about 20% between the panes.

With current commercial switchable glass, as the temperature of the glass increases from absorption of light by the thin colored film that modulates light transmission, infrared radiation is re-radiated inside the room, decreasing the energy-saving efficiency of the glass.

Scientists have been searching for a reflective material that modulates light by reflection rather than by absorption. In 1996, a research group in the Netherlands developed thin films based on yttrium and lanthanum with a thin layer of palladium which could be switched between transparent and reflective states by hydrogenation and dehydrogenation reactions. But the elements are rare and expensive. A research group at the Lawrence Berkeley National Laboratory developed a thin-film switchable mirror made of a magnesium-nickel alloy, but it has a dark brown color, even in its transparent state.

Reflective state

Since 2002 the Energy Control Thin Film Group at AIST has been developing a thin film made of magnesium-nickel alloy, but they were unable to make the materials color-neutral in their transparent state, so they explored the possibility of creating a thin film using a magnesium-titanium alloy, which resulted in a film almost color-neutral in its transparent state.

The Energy Control Thin Film Group applied magnesium and titanium metals simultaneously onto a glass plate to make a thin layer of alloy about 40-nm thick. Over that, they applied a thin layer of palladium about 4-nm thick.

The thin film forms a reflecting mirror when it is applied to the glass, but turns transparent when it is exposed to an atmosphere that contains hydrogen but no oxygen. It reverts to a reflective state when it is exposed to an atmosphere that contains oxygen but no hydrogen. Switching is achieved by introducing gas containing a low concentration of hydrogen (about 1%) or gas containing oxygen (about 20%) into the space between the panes. Small amounts of hydrogen and oxygen for use in the switching process can be readily generated by decomposition of water. The trial switchable mirror created by the Energy Control Thin Film Group showed “excellent switching characteristics,” and the group believes it is the first full-size sample of switchable mirror glass ever to be produced.

Now, the group is working on the technology to increase the durability of the switchable mirror control by reducing the deterioration as a result of repeated cycles of switching. At the same time, because the thin film can be formed on various transparent materials besides glass, they are developing various switchable mirror films coated with this material as part of the “Strategic Development of Rationalization Technology for Energy Usage” project sponsored by the New Energy and Industrial Technology Development Organization. The group hopes it can further develop the new thin film so “we conserve energy simply by applying it to windows.”