Nanowires have the power to drastically advance solar energy

Tuesday, April 9, 2013

Imagine a solar panel more efficient than today's best solar panels, but using 10 000 times less material. This is what EPFL researchers expect given recent findings on these tiny filaments called nanowires. Solar technology integrating nanowires could capture large quantities of light and produce energy with incredible efficiency at a much lower cost. This technology is possibly the future for powering microchips and the basis for a new generation of solar panels.

Despite their size, nanowires have tremendous potential for energy production. "These nanowires capture much more light than expected," says Anna Fontcuberta i Morral about her research, published on 24 March 2013 in Nature Photonics.

Nanowires are extremely tiny filaments?in this case able to capture light?with a diameter that measures tens to hundreds of nanometers, where a nanometer is one millionth of a millimeter. These miniscule wires are up to 1000 times smaller than the diameter of human hair, or comparable in diameter to the size of viruses.

When equipped with the right electronic properties, the nanowire becomes a tiny solar cell, transforming sunlight into electric current. Anna Fontcuberta i Morral and her team built a nanowire solar cell out of gallium arsenide, a material which is better at converting light into power than silicon. They found that it actually collects more light than the usual flat solar cell?up to 12 times more?and more light means more energy.

The nanowire standing vertically essentially acts like a very efficient light funnel. Even though the nanowire is only a few hundred nanometers in diameter, it absorbs light as though it were 12 times bigger. In other words, it has a greater field of vision than expected.

Fontcuberta's prototype is already almost 10% more efficient at transforming light into power than allowed, in theory, for conventional single material solar panels. Furthermore, optimizing the dimensions of the nanowire, improving the quality of the gallium arsenide and using better electrical contacts to extract the current could increase the prototype's efficiency.

Arrays of nanowire solar cells offer new prospects for energy production. This study suggests that an array of nanowires may attain 33% efficiency, in practice, whereas commercial (flat) solar panels are now only up to 20% efficient. Also, arrays of nanowires would use at least 10 000 times less gallium arsenide, allowing for industrial use of this costly material. Translating this into dollars for gallium arsenide, the cost would only be $10 per square meter instead of $100 000.

Free to the engineer's imagination to mount these nanowires onto a variety of substrate panels, be it lightweight, flexible or designed to withstand the harshest of conditions. In a world where energy consumption is on the rise, these nanowires may one day power everything from your favorite gadget to space missions to Mars.

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Ecole Polytechnique F?d?rale de Lausanne: http://www.epfl.ch/index.en.html

Thanks to Ecole Polytechnique F?d?rale de Lausanne for this article.

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Source: http://www.labspaces.net/127646/Nanowires_have_the_power_to_drastically_advance_solar_energy

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Ex-'Pretty Little Liars' actor pleads guilty in NY

NEW YORK (AP) ? A former actor on ABC's "Pretty Little Liars" has pleaded guilty to misdemeanor larceny for lifting $7,000 in electronics and jewelry from a friend's Manhattan apartment.

Parker Bagley took the plea on Monday in Manhattan Criminal Court.

As part of the plea, the 23-year-old agreed to pay half of the $7,000 on Monday. The remainder is due in June.

He had faced 3rd-degree grand larceny, which carries up to seven years in prison.

Bagley quipped outside court: "I'm just glad they didn't find the bodies. That would have been bad."

Bagley starred as Jason in the teen mystery drama. He says he's now focusing on his music.

Source: http://news.yahoo.com/ex-pretty-little-liars-actor-pleads-guilty-ny-114921326.html

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Switched On: Unconventional, but not uncompromising

Each week Ross Rubin contributes Switched On, a column about consumer technology.

For T-Mobile, March went out like a lion, a roaring one. With passion for both invention and invective, T-Mobile roared against the contract during its UnCarrier announcement. The nation's fourth-largest (post-carrier) wireless operator will support its move away from contracts with a television spot that shows it as one of four bad guys riding into town to get people to do things their way, but then trades in its "black hat" for a magenta one as it no longer seeks to enforce those policies. T-Mobile says to watch carefully as each of the other bad guys has a distinct personality that reflects one of its main competitors.

T-Mobile is in a battle for getting consumers onto a network that is described as 4G, but evaluating the appeal of its announcement comes down to looking at four S's - subsidy, selection, speed and simplicity.

Filed under: Cellphones, Misc, HTC, T-Mobile, Facebook

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Source: http://www.engadget.com/2013/04/07/unconventional-but-not-uncompromising/

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Serbia rejects Kosovo deal, begs EU for more time

By Aleksandar Vasovic and Matt Robinson

BELGRADE (Reuters) - Serbia on Monday rejected a European Union-brokered plan to tackle the ethnic partition of its former province Kosovo, a move that could hurt Belgrade's hopes of starting membership talks with the bloc.

But the coalition government called for the "urgent" continuation of negotiations to reach an accord, with the EU set to consider this month whether to recommend the start of accession talks with Serbia.

Membership talks would mark a major milestone in Serbia's recovery from a decade of war and isolation under late strongman Slobodan Milosevic and provide a much-needed boost for its ailing economy, still the biggest in the former Yugoslavia.

The EU had set a Tuesday deadline for Kosovo and Serbia to accept the principles on the table after talks ended last week without result. Kosovo, which broke away from Serbia in a 1998-99 war and declared independence in 2008, had already said it was ready to sign the deal.

Facing a potential backlash from hardliners and a warning from the influential Orthodox Church, Serbia balked, saying the offer fell far short of the broad autonomy it wants for a small Serb enclave of majority ethnic Albanian Kosovo.

"The government of Serbia calls for the urgent continuation of dialogue ... with the mediation of the EU in order to reach a lasting solution," the government said in a declaration read out by Prime Minister Ivica Dacic at a meeting of his cabinet.

"The government of Serbia cannot accept the proposed solution as it does not guarantee the safety and human rights of Serbs in Kosovo," he said.

But it was unclear whether the EU might agree to one last push to negotiate a deal.

The cabinet voted unanimously to adopt the declaration, which will be forwarded to EU foreign policy chief Catherine Ashton.

Ashton is due to issue a progress report on the situation on April 16 that will likely decide whether the EU launches Serbia on the long path of accession talks this year.

MORE NEGOTIATIONS?

Neighboring Croatia, Serbia's wartime foe during the collapse of Yugoslavia, is set to become the EU's 28th member on July 1, but Belgrade's progress has long been hamstrung by its refusal to come to terms with Kosovo's secession.

The West wants Belgrade to cede its fragile hold on a northern, Serb-populated pocket of Kosovo, where ethnic Albanians are the 90-percent majority - an ethnic partition that frequently flares into violence and has frustrated NATO plans to cut back its now 6,000-strong Kosovo peacekeeping force.

In a major U-turn in policy, Serbia has offered to recognize the authority of the Pristina government over the entire territory of Kosovo, but wants broad autonomy for the 50,000 Serbs living in the north.

Full details of the EU-brokered proposal have not yet been made public, but Belgrade made clear it fell short of its demands, particularly that the north control its own police and judiciary.

Ashton had said a marathon 12-hour meeting last week between the leaders of Kosovo and Serbia, which ended without result, would be the last. But the EU's envoy to Serbia appeared to hold out the possibility of another round.

"It's up to Ashton to decide if the process will be continued, since she herself said that the differences are small but the gaps are deep, and when the answers arrive tonight she will decide whether the process can be continued," Ambassador Vincent Degert said, according to the Tanjug state news agency.

Serbia lost control over Kosovo in 1999 when NATO launched 11 weeks of air strikes to halt the killing and expulsion of ethnic Albanians by Serbian forces waging a brutal counter-insurgency campaign under Milosevic.

Considered by many Serbs as the cradle of their nation and Orthodox Christian faith, the territory of 1.7 million people declared independence in 2008 and has been recognized by more than 90 countries, including the United States and 22 of the EU's 27 members.

(Writing by Matt Robinson)

Source: http://news.yahoo.com/serbia-reject-kosovo-deal-begs-eu-more-time-123502732.html

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Pentagon struggles with high cost of health care

WASHINGTON (AP) ? The loud, insistent calls in Washington to rein in the rising costs of Social Security and Medicare ignore a major and expensive entitlement program ? the military's health care system.

Despite dire warnings from three defense secretaries about the uncontrollable cost, Congress has repeatedly rebuffed Pentagon efforts to establish higher out-of-pocket fees and enrollment costs for military family and retiree health care as an initial step in addressing a harsh fiscal reality. The cost of military health care has almost tripled since 2001, from $19 billion to $53 billion in 2012, and stands at 10 percent of the entire defense budget.

Even more daunting, the Congressional Budget Office estimates that military health care costs could reach $65 billion by 2017 and $95 billion by 2030.

On Wednesday, when President Barack Obama submits his fiscal 2014 budget, the Pentagon blueprint is expected to include several congressionally unpopular proposals ? requests for two rounds of domestic base closings in 2015 and 2017, a pay raise of only 1 percent for military personnel and a revival of last year's plan to increase health care fees and implement new ones, according to several defense analysts.

Defense Secretary Chuck Hagel insisted this past week that the military has no choice as it faces a $487 billion reduction in projected spending over the next decade and possibly tens of billions more as tea partyers and other fiscal conservatives embrace automatic spending cuts as the best means to reduce the government's trillion-dollar deficit.

The greatest fiscal threat to the military is not declining budgets, Hagel warned, but rather "the growing imbalance in where that money is being spent internally." In other words, money dedicated to health care or benefits is money that's not spent on preparing troops for battle or pilots for missions.

Hagel echoed his predecessors, Leon Panetta, who said personnel costs had put the Pentagon on an "unsustainable course," and former Pentagon chief Robert Gates, who bluntly said in 2009 that "health care is eating the department alive."

In his speech last past week, Hagel quoted retired Adm. Gary Roughead, the former Navy chief, who offered a devastating assessment of the future Pentagon.

Without changes, Roughead said, the department could be transformed from "an agency protecting the nation to an agency administering benefit programs, capable of buying only limited quantities of irrelevant and overpriced equipment."

The military's health care program, known as TRICARE, provides health coverage to nearly 10 million active duty personnel, retirees, reservists and their families. Currently, retirees and their dependents outnumber active duty members and their families ? 5.5 million to 3.3 million.

Powerful veterans groups, retired military officer associations and other opponents of shifting more costs to beneficiaries argue that members of the armed forces make extraordinary sacrifices and endure hardships unique to the services, ones even more pronounced after a decade-plus of wars in Iraq and Afghanistan.

Members of the military have faced repeated deployments, had to uproot their families for constant moves and deal with limits on buying a home or a spouse establishing a career because of their transient life. Retirement pay and low health care costs are vital to attracting members of the all-volunteer military.

"If you don't take care of people, they're not going to enlist, they're not going to re-enlist," said Joe Davis, a spokesman for the Veterans of Foreign Wars.

Resistance in Congress to health care changes was evident in the recently passed spending bill to keep the government running through Sept. 30. Tucked into the sweeping bill was a single provision stating emphatically that "none of the funds made available by this act may be used by the secretary of defense to implement an enrollment fee for the TRICARE for Life program."

The program provides no-fee supplemental insurance to retirees 65 and older who are eligible for Medicare. The Pentagon repeatedly has pushed for establishment of a fee, only to face congressional opposition.

The provision in the spending bill blocking an enrollment fee had widespread support among Republicans and Democrats, according to congressional aides. The Pentagon, nonetheless, is expected to ask again in the 2014 budget for an enrollment fee.

The department also is likely to seek increases in fees and deductibles for working-age retirees and try again to peg increases in them to rising costs as measured by the national health care expenditure index produced by the Centers for Medicare and Medicaid Services. That index rose 4.2 percent in 2012 and is projected rise by 3.8 percent this year.

In recent years, Congress has agreed to tie any future increases to the typically smaller percentage increase in military retirees' cost-of-living adjustment, which this year is 1.7 percent.

Either way, a military retiree under age 65 and their family members pay a far smaller annual enrollment fee than the average federal worker or civilian ? $230 a year for an individual, $460 for a family. There is no deductible.

Lawmakers' other response was to establish the Military Compensation and Retirement Modernization Commission to study the issue of benefits and offer recommendations on how the Pentagon can address the problem. The commission was created in this year's defense authorization bill.

"Nobody wants to touch it because people are confused about who it impacts," said Lawrence Korb, a former assistant defense secretary and now a senior fellow at the liberal-leaning Center for American Progress. "It's not going to impact people on active duty. It's not going to impact veterans because they're taken care of by the VA. Basically (it's) working-age retirees."

Korb said he wished Hagel has been more explicit in his warning about the impact of benefit costs.

"He did lay it out that we're going to have to do something or we're going to end up like General Motors and spending everything on people not working for us anymore."

Gordon Adams, a professor at American University who was a senior official at the Office of Management and Budget, said limited savings in the short term from changes in retirement rules or other benefits present a challenge in making the case for change.

"The savings are downstream, but you only get downstream if you get in the boat now," Adams said. "Otherwise you never get downstream, you're just waiting at the dock all the time because you don't think it'll save you money up front."

_____

Follow Donna Cassata on Twitter: http://twitter.com/DonnaCassataAP.

Source: http://news.yahoo.com/pentagon-struggles-high-cost-health-care-075320388--politics.html

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Reducing waste of food: A key element in feeding billions more people

Apr. 7, 2013 ? Families can be key players in a revolution needed to feed the world, and could save money by helping to cut food losses now occurring from field to fork to trash bin, an expert said in New Orleans on April 7. He described that often-invisible waste in food -- 4 out of every 10 pounds produced in the United States alone -- and the challenges of feeding a global population of 9 billion in a keynote talk at the 245th National Meeting & Exposition of the American Chemical Society, the world's largest scientific society.

"We will need another 'Green Revolution' to feed the world by 2050," said John Floros, Ph.D., referring to the development of high-yield, disease-resistant breeds of grain and other agricultural innovations that took root in the 1960s. "That will mean scientific innovations, such as new strains of the big three grains -- rice, wheat and corn -- adapted for a changing climate and other conditions. It also will require action to reduce a terrible waste of food that gets too little attention."

Floros cited estimates that in many developing countries up to half of the food harvested from farmers' fields is lost before reaching consumers. He is dean of the College of Agriculture at Kansas State University. That waste can occur due to spoilage from improper storage of grain during transportation or from pests. Rats and mice alone eat or spoil 20 percent of the world's food supply due to contamination with their urine and feces.

"A different kind of waste occurs in the United States and some other developed countries," Floros said. "Developed countries have much more efficient systems for preserving, storing, transporting and protecting food from spoilage and pests. But as a nation -- households, supermarkets, restaurants, other food-service providers -- we throw away about 4 out of every 10 pounds of food produced each year."

Government studies show, for instance, that the average family in the United States throws away 20 pounds of food a month, more than $2,000 worth every year for a family of four. It includes food that has gone uneaten and spoiled in refrigerators and on pantry shelves, as well as food that people throw away after cooking. Uneaten food actually rivals paper, plastic and other refuse as the No. 1 material in some municipal landfills.

Scientists know that food waste in landfills, for instance, releases methane gas as it decomposes. Methane is about 20 times more potent than carbon dioxide as a greenhouse gas that fosters global warming. Floros pointed out that reducing food waste would contribute to solving other great global challenges that society faces in the 21st century, beyond feeding a booming population. Wasting food wastes the freshwater needed to grow it, at a time when 1.2 billion people lack access to clean water. It also wastes energy, fertilizers, pesticides and other resources used in the food supply.

Supplying more food, however, is only part of the challenge, Floros emphasized. "Millions of people in some developing countries are becoming more affluent. In the past, people were satisfied with food that filled them up and sustained life. Increasingly, they will demand food that is convenient to prepare, certified as safe and highly nutritious and tastes good."

He cited the People's Republic of China as an example. The middle class in China is now larger than the U.S. population and is increasing in size year by year. And people in China are now consuming almost 3 times as much meat compared to a few decades ago. Demand for convenience foods also is rising with the growth of the urban population.

Several other food-related challenges lie ahead, Floros pointed out. Water, for instance, is becoming scarcer, as is fertile farmland. Global climate change may stress those resources even further. The demand for sustainable energy may divert more cropland to production of crops for biofuel production. Economic conditions threaten less investment in agricultural research and development. Drought and other extreme weather could impact food production. And consumption of too much food and less nutritious foods underpins epidemics in obesity and type 2 diabetes.

"We're not doing enough to resolve these complex issues that are critical for providing 9-10 billion people with a nutritious diet," said Floros. "Consumers, industry, universities and governments all need to pitch in. The first step is more awareness of these issues and the need for action on multiple levels of society."

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The Engadget Interview: Mark Setrakian of Syfy's Robot Combat League (video)

From the latest harbinger of the robopocalypse from Boston Dynamics to more friendly looking machines like Romo, Engadget has a longstanding love affair with all forms of robots. Syfy channel's newest show, Robot Combat League (RCL), has provided us with twelve new objects of robotic affection --and the best part is, we get to watch them destroy each other in gladiatorial fashion. RCL isn't the first show to have 'bots do battle on TV, of course, but it is the first to have the robots be humanoid avatars that mimic the movements of the people operating them. Mark Setrakian is the man who designed and built the dozen robots on the show, and we recently got the opportunity to chat with him about how he did it.

Filed under: Robots

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Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/MTc1RIuQdjs/

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