Cellulari e computer di ultima generazione, lampade led, celle solari. Tutti gli oggetti elettronici e le applicazioni tecnologiche più all’avanguardia contengono metalli, come piombo, cadmio, oro, cobalto. Risorse in parte rare, estratte e trasformate con un grande impatto sull’ambiente e dispendio di energia. Ma, soprattutto, risorse esauribili. Quando termineranno, molte delle attuali tecnologie potrebbero finire con esse. Cosa fare allora? Per prima cosa, tirare fuori dai cassetti i vecchi cellulari e i computer in disuso. In una parola, riciclare. È il motto dell’United Nations Environment Programme (Unep) e del rapporto Recycling rates of metals: a status report, lanciato durante la Green Week dell’Unione europa. Secondo cui la percentuale di recupero è ancora drammaticamente bassa.

Soltanto 18 dei 60 metalli presi in esame ha un tasso di riciclo superiore al 50 per cento, con percentuali più basse in alcune economie emergenti; 34 elementi sono addirittura sotto l’1 per cento. Questo nonostante le grandi potenzialità del riutilizzo. “A differenza di altri materiali, i metalli sono interamente riciclabili”, ha dichiarato il direttore esecutivo dell’Unep Achim Steiner durante la conferenza di Bruxelles. “Possono essere usati più e più volte, minimizzando la necessità di nuove estrazioni e i processi di trasformazioni dei materiali vergini, evitando sprechi di acqua e di energia, e salvaguardando quindi l’ambiente”. Come sottolinea anche il rapporto infatti, riciclare i metalli è dalle due alle dieci volte più efficiente, dal punto di vista energetico, che fonderli dopo l’estrazione. Proprio l’estrazione mineraria, inoltre, da sola incide per il 7 per cento sul consumo mondiale di energia, con emissioni che contribuiscono significativamente al cambiamento climatico.

Il piombo è il metallo più riutilizzato: quasi l’80 per cento dei prodotti che contengono componenti in piombo, soprattutto batterie, va al riciclo. Più della metà del ferro e altri componenti principali di acciaio e acciaio inox, come anche platino, oro, argento e altri metalli preziosi, viene recuperato. Con delle differenze, però. Per esempio, il 70-90 per cento dell’oro utilizzato nelle applicazioni industriali viene riciclato, contro solo il 10-15 per cento di quello derivante dai beni elettronici. Tra i metalli con un tasso di riciclo che va dal 25 al 50 per cento abbiamo il magnesio, il molibdeno e l’iridio.

Tugsteno, rutenio (usato nell’elettronica e nell’elettrochimica) e cadmio, invece, fanno registrare tassi di riciclo dal 10 al 25 per cento. È inferiore al 10 per cento il recupero del mercurio e dell’antimonio, mentre ultimi in classifica troviamo metalli fondamentali per l’industria elettronica e per la green economy: l’indio (usato nei semiconduttori , nelle lampade a risparmio energetico, nel fotovoltaico), il gallio (diodi, led, celle solari), il selenio (led, fotovoltaico, ottica a infrarossi), il tellurio (termo-elettronica e celle solari), il neodimio e il diprosio (magneti per turbine solari) e il lantanio (batterie dei veicoli ibridi).

Di questo passo, le economie mondiali perderanno la possibilità di fare scorta in vista dell’esaurimento delle risorse, e buona parte delle tecnologie del futuro potrebbe non vedere mai la luce. Secondo un altro rapporto, “Decoupling: natural resource use and environmental impacts from economic growth”, illustrato sempre ieri dall’International Resource Panel dell’Unep, entro il 2050 l’umanità potrebbe arrivare a consumare ogni anno qualcosa come 140 miliardi di tonnellate di minerali, metalli, combustibili fossili e biomasse: tre volte ciò che consumiamo oggi. L’era degli approvvigionamenti facili e a prezzi ragionevoli, quindi, sembra che stia per finire.

Gli esperti propongono una serie di raccomandazioni: in primis ridurre il consumo di risorse per ciascuna attività economica, secondo, incoraggiare design che rendano più semplice la scomposizione dei prodotti, migliorare la gestione e il riciclo dei rifiuti nei paesi in via di sviluppo, e invogliare gli abitanti di quelli sviluppati a riciclare vecchi cellulari, cavi usb e computer. Solo questo permetterebbe di risparmiare miliardi di tonnellate di emissioni di gas serra e di creare nuovi posti di lavoro.

Fonte: galileonet.it

The National Renewable Energy Laboratory is the Department of Energy's green tech incubation lab, so perhaps it's no surprise that the research agency is attempting to lead America to greener pastures by example. The NREL just put the finishing touches on its new Research Support Facility (RSF) in Golden, Colo., -- the largest zero-energy office building in the nation -- hoping other developers will follow its lead.

The 220,000 square-foot facility will be home to more than 800 employees when it opens its doors in August, and is expected to achieve platinum LEED certification, the highest distinction a building can get from the U.S. Green Building Council. To create a structure that consumes no more energy than it produces in a year, the engineers behind the office complex took into account both the technologies of the future and the building practices of the past.

For instance, before electric lighting and climate control became ubiquitous architects situated and designed buildings to take advantage of natural light, with lots of windows that also provided ventilation. A slender 60-foot width and an east-west orientation allow lots of natural daylight to illuminate interior spaces of the RSF. That centuries-old building practice is coupled with smart technology that constantly compares interior and exterior temperatures, and even sends messages to occupants' computer screens when its time to open or close the windows for optimum natural climate control.

The building is also built largely of recycled or reclaimed materials, and the exterior is designed to absorb heat from the sun that can then either contain the heat during the day during warmer months or release it into the building during cooler months. The interior climate is further controlled using an radiant system that uses water pipes embedded in the floor to circulate either hot or cold water.

Of course, the NREL's new green building pales in comparison to China's ambitious 800,000 square-foot "Sun Dial" office building or the scope of projects like Masdar City outside Abu Dhabi. But it's a good -- and good looking -- first step toward better building practices. To make sure the drive for net-zero architecture doesn't stall in Golden, the NREL will be offering its design for the building to developers for free starting this fall.

Source: PopSci

Geoff Dembicki reports extensively on the growing political influence of Alberta's oil sands industry and other climate change-related issues for TheTyee.ca, an award-winning online newspaper based in Vancouver, Canada.

Driving south from Vancouver, Canada, towards Seattle, the scenery is perfectly pastoral with rolling hills and grazing cows. But suddenly, dominating the horizon, the view is interrupted by a phalanx of refinery towers shooting white-gray plumes into the sky. These industrial spires of BP's Cherry Point refinery loom high over Whatcom county, a lush border region a little more than 100 kilometers north of Seattle.

Washington State's largest refining complex provides jet fuel, gasoline and diesel to markets up and down the west coast of North America. I had driven there on a rainy morning last month, hoping to learn more about the economic alchemy that transforms crude oil from Alberta's oil sands and elsewhere into ever ubiquitous aluminum beverage cans.

Photo by Dustin Hicks

Cherry Point plays a little known but critical role in the manufacture of these cans - in fact one-sixth of the world's output would not be possible without an industrial substance produced here in massive volumes each day.

Every year 100 billion soda, beer, and juice cans are cracked open by North Americans each year, almost one can for every person every day. That vast market suggests that transitioning off fossil fuels to halt climate change will be more complicated than the oft-proclaimed solution of switching to a greener forms of transportation.

From Alaska to Alberta

Inside a low brick building at the front of the BP refinery, I shook hands with Bill Kidd, BP's local director of external affairs. “How're you doing?” he exclaimed with a broad smile that made lines appear at the corners of his eyes.

The 52-year-old Kidd, dressed smartly in sleeveless black sweater, slacks and white dress shirt, led me to what passes here as a spacious corner office. Here he explained how Cherry Point is a showcase of North America's oil-boom past and its more troubled future. With the dwindling of easy oil that has gushed from the ground for the last century, the energy industry is in a full-bore search for rich, new reserves, including the oil sands of western Canada.

Built by the Atlantic Richfield Company (ARCO) in 1971 specifically to process crude oil shipped from Alaska's North Slope, Cherry Point was acquired by British Petroleum after the two companies merged in 2000. Today BP (the company dropped the original name in 2001) has become North America's largest oil and gas producer. The company generated profits of US$16.6 billion in 2010 even after a deadly explosion at its offshore Gulf of Mexico Macondo rig created the worst environmental disaster in U.S. history.

For over a decade, the massive Prudhoe Bay reserves and other frigid deposits nearby helped supply refineries on the west coast. Indeed Cherry Point still memorializes those early glory days with a four-foot tall sculpture of a flower with sheet metal petals surrounding an old Prudhoe Bay drill bit.

But production, which peaked at 2.1 million barrels per day in 1989, “has fallen off a cliff,” Kidd told me. Today, daily yield has plummeted to just over 600,000 barrels.  

The refinery now sources only half its oil from Alaska, with places as varied as West Africa and Russia helping make up the difference, Kidd said. Most significantly, up to 14 percent of Cherry Point's current crude supply can be traced back to Alberta's vast oil sands reserves, according to trade research conducted by the Borealis Centre for Environment and Trade Research, based on data from the U.S. Department of Energy.

“How much we use specifically is sensitive information,” Kidd told me when I asked him about the figure. “But that is not an outlandish number.”

From Crude to Can

About 90 percent of the crude oil that gets pumped into Cherry Point comes out as gasoline, diesel and jet fuel - the bread and butter of North America's refining industry. But the Washington state complex is unique in that it is one of the world's leading providers of a substance essential to the aluminum industry.

When transportation fuels are separated from crude oil, they leave behind a tarry residue. Break down that substance with high temperatures and pressure, and it becomes petroleum coke, a valuable industrial solid. Petcoke, as it is known, gives off intense heat when it burns, making it ideal for the production of cement, steel and certain specialty chemicals. It is also extremely carbon-intensive, releasing almost double the greenhouse emissions of natural gas.

At Cherry Point, some of this petcoke is sent via conveyor belt to the calciner, a collection of large hearths that Kidd compared to a “2,300F degree coffee roaster.”

The finished product, “calcined coke,” is then loaded onto tankers and shipped to aluminum smelters in Australia, Brazil, New Zealand, Canada, and South Africa, according to Borealis. Those smelters in turn outsource their metal to beverage can producers around the world.

When you follow the supply chain all the way back, “one in six aluminum cans is made using BP Cherry Point's calcinated coke,” the company's website brags.

It used to be that most of the refinery's output stayed onshore, Kidd said. Only a generation ago, the U.S. aluminum industry was thriving, shipping 7.3 million tons of metal in 1973, up 21 percent from the year before.

But a booming trend towards global trade hit domestic smelters fast and hard. “Nearly all our aluminum in the next century is probably going to come from offshore countries,” a spokesperson from Ferndale's smelter, only a few kilometers south of Cherry Point, lamented in 1986. The industry could not escape the same economic factors that killed off domestic steel production: relatively high labor and energy costs.

Energy Security

Tune into any discussion on the future of U.S. oil supply and you're going to hear the phrase “energy security” an awful lot. . The debate's gained even more urgency since the Paris-based International Energy Agency (IEA) announced late last year that world conventional oil production likely peaked in 2006.

Critics of continued reliance on fossil fuels argue that these dwindling conventional oil reserves mandate a switch to renewable or even nuclear power. The oil industry however is banking on a different strategy. Notably Republican legislators in the U.S., oil industry lobbyists and Canada's own prime minister, Stephen Harper, have seized onto this fear as a way to promote the oil sands business.

Cherry Point, by relying on the oil sands for up to 14 percent of its crude supply, is helping push the shift from crude oil to unconventional sources. And though the refinery isn't currently considering the pricey upgrades that would let it process even more, BP's Kidd said the prospect isn't too hard to imagine.

“This refinery was built when you had a huge pool of crude in Alaska, the biggest gasoline markets in the world in California and we were right in between. Now you're just moving the supply a little bit east,” he said. “I think it's reasonable to think that more [oil sands] will come this way.”

The refinery's supply-chain narrative - once mighty oil fields in decline, greater reliance on higher-carbon unconventional sources - is being replayed globally. Other North American refineries - such as BP's Whiting complex in Indiana - have invested billions of dollars to handle fast-growing shipments of oil sands crude.

The plan to bring the oil industry into line with changing conditions also includes Keystone XL, a proposed 3,200 kilometer mega-pipeline that travels south from the Canadian province of Alberta to refineries lining the Gulf coast of Texas.

Supporters such as TransCanada, the company proposing to build it, say Keystone XL would “reduce dependence on foreign oil from the Middle East and Venezuela,” and thereby “improve U.S. energy security.”

Toxic “Mordor”

One of the main reasons why environmental activists oppose this strategy is the impact that the extraction of oil sands have on the province of Alberta, a thousand kilometers to the north west of Cherry Point.

There are up to an estimated 2.5 trillion barrels of crude waiting to be extracted in Alberta. This makes the oil sands North America's largest single source of petroleum, far surpassing Saudi Arabia. But developing those reserves is not an easy - or pretty -- task. Each barrel of oil sands crude must either be clawed from frigid muskeg bogs with industrial-scale shovels, or melted out of underground formations with high-pressure steam and toxic chemicals.

A United Nations water advisor in 2008 compared the region's strip-mined panoramas and sprawling toxic lakes to Mordor, the fictional dark realm of Middle Earth created by J. R. R. Tolkien.

“The air is foul, the water is being drained and poisoned and giant tailing ponds line the Athabasca River,” Canadian environmentalist and author Maude Barlow said at the time.

Alberta's oil sands industry also produces 23 percent more greenhouse gas emissions per barrel than more conventional operations such as those in Prudhoe Bay, a recent European Union report estimated.

The provincial government has argued that report is “unfair” because it uses out-of-date figures. And in 2009 outgoing premier Ed Stelmach told an economic forum in Geneva, Switzerland, that “no matter which extraction method is used, Alberta has some of the most stringent environmental regulations in the world.”

Climate Change Threat

The other reason that critics cite in opposing the oil sand industry is global warming. Only days after I drove to Cherry Point, delegates from more than 180 countries were gathering in Bonn, Germany, for two weeks of climate talks. The mood on day one was sombre as they were confronted by an IEA report showing that greenhouse gases were at record highs, despite 20 years of attempts to control them.

“A serious setback,” is how the IEA's chief economist, Fatih Birol, described the figures.

Part of the reason is that global oil consumption is not going down even though supplies of easy-to-access conventional oil, the very commodity that made a global trade in aluminum cans possible, likely peaked five years ago, as the IEA pointed out last November.

Instead the IEA expects that oil sands, oil shale and extra heavy crude - among the most greenhouse gas-intensive fuel sources on the planet - are filling the gap and are projected to make up roughly 11 percent of global supply by 2030.

This trend “risks tipping the world over the brink in terms of climate damage,” according to a 2010 report by Friends of the Earth Europe.

Yet a radical shift in global efforts to fight climate change -one of the most pressing crises in human history -- seems less and less likely each year. If the world's nations can't limit the Earth's average temperature rise to two degrees above pre-industrial levels, scientists predict that everything from global agriculture to the world's coastal cities will be in peril.

Many environmentalists believe the Obama administration can make a difference by canceling TransCanada's Keystone XL proposal, a pipeline that would pump 800,000 barrels of high-carbon Alberta oil sands crude into the U.S. every day.

“The best way to build energy security in America is through clean, home-grown sources of energy that won't run out -- such as wind and solar for electric vehicles and fuel efficiency and smart growth to reduce our dependence on oil,” Natural Resources Defense Council's Susan Casey-Lefkowitz wrote earlier this year.

Yet switching power and transportation sources are only part of the answer. Closing up my interview at the Cherry Point refinery, I asked Kidd how North America can possibly square its global warming goals with a fossil fuel industry so ubiquitous it's difficult to imagine life without it.

“Obviously,” he replied, the smile now gone from his face, “we're going to have to do something radically different.”

I asked Kidd one final question: “Could we have a global pop, beer and juice can industry without crude oil?”

“Nope,” he replied. “Hydrocarbons in general are incredibly ubiquitous in our economic engine. It isn't just transportation fuel that will be the issue.”

On my drive back to Vancouver I saw crude oil wherever I looked - like an invisible coating on every concrete overpass, eighteen-wheeler semi-truck and pop can discarded on the side of the road.

The question of “energy security” had never seemed so complex.

Source: CorpWatch.org

A rivelare l'evento è stata l'individuazione dei raggi gamma (Grb) relativi all'esplosione da parte del satellite Swift della Nasa. Si tratta del più antico fenomeno cosmico mai osservato e, forse, dell'oggetto più lontano nel tempo e nello Spazio conosciuto finora. Il team internazionale di astronomi che sta studiando i Grb, di cui fanno parte due italiani dell’Istituto Nazionale di Astofisica (Inaf), ha presentato al congresso nazionale dell’American Astronomical Society (conclusosi ieri a Boston) i primi dati; lo studio sarà poi pubblicato su The Astrophysisical Journal.

Dopo la segnalazione da parte del satellite Swift, avvenuta il 29 aprile del 2009, le prime osservazioni terrestri sono state effettuate grazie ai telescopi Grond e Vlt, installati sulle Ande cilene. Subito dopo è entrato in azione anche il telescopio Gemini, sul vulcano Mauna Kea, nelle Hawaii, coordinato da Antonino Cucchiara, ricercatore italiano trasferitosi da poco a Berkeley. Per dissipare ogni dubbio sulla distanza dell'esplosione è stato chiamato in causa anche il telescopio spaziale Hubble, che ha fornito un'immagine a colori del cielo nelle vicinanze della sorgente dei Grb. Tutti i dati raccolti da questi strumenti sono stati esaminati da un gruppo di ricercatori guidato da Lorenzo Amati dell’Inaf-Iasf di Bologna; Ora i risultati sono stati resi pubblici.

L'esplosione sarebbe avvenuta esattamente 13 miliardi e 104 milioni di anni fa, quando l'Universo era ancora molto giovane. I due lampi di raggi gamma che ne sono scaturiti – ognuno della durata di una decina di secondi – hanno attraversato lo Spazio raggiungendo solo qualche settimana fa la Terra, a distanza di sei giorni l'uno dall'altro. Unificati sotto il nome di GRB 090429B, si contendono il titolo di "oggetto più lontano nell'Universo" con un altro lampo di raggi gamma chiamato GRB 090423 e con due galassie: Lehnert e Bouwens (la più quotata).

“La scoperta di un’esplosione cosmica così distante, avvenuta in un’epoca in cui l’Universo aveva meno del 4 per cento dell’età attuale, è di grande interesse per lo studio della sua storia”, ha commentato Paolo D'Avanzo dell’Osservatorio Astronomico Inaf di Brera, coatuore dello studio.

Fonte: galileonet.it - Riferimenti: Inaf

Next-generation soap!

Waterborne disease kills three children every minute. This handheld device, called Kopper – which costs only $A2.50 to make – could prevent some of these deaths.

Designed by Balin Lee, a graduate of the University of Western Sydney, it removes 99.99 per cent of all parasites, viruses and bacteria found in contaminated water.

The device works by squeezing water through a microfilter, removing anything larger than 0.1 micrometre, which includes Escherichia coli and Giardia. It then fries anything left with electrolysis, which splits the oxygen and hydrogen molecules, removing tinier pathogens in the water.

Kopper is powered by piezoelectric generators that convert kinetic energy into an electrical current: powering the device requires only a few shakes.

(Image: Balin Lee/SRD Change)

Slum reshaping, breathing buildings and next-generation soap are just some of the ideas on display at the annual SRD Change Exhibition in Sydney, Australia. The show flaunts the best in sustainable and environmental design aiming "to create products and services that focus on tangible and positive benefits for society in every possible aspect", says Greg Campbell, the SRD Change curator.

Source: NewScientist.com

Spintronics — also known as magnetoelectronics — may replace electronics as the medium of choice for computer memory. The discovery of a mechanism that produces permanent magnets at room temperature, without any external influence, may soon improve the design of spintronic devices. Takumi Ohtsuki from the RIKEN SPring-8 Center, Harima and his colleagues in Japan, made the discovery in a class of material called a dilute ferromagnetic oxide.

A representation of a thin film of Co:TiO2 in which ferromagnetism arises because titanium 3d electrons (green) travel around the material aligning the spin of cobalt atoms (pink) so that they all point in the same direction. The blue and brown spheres correspond to titanium and oxygen atoms, respectively. Credit: 2011 Takumi Ohtsuki

Ferromagnetism is the mechanism responsible for making some materials magnetic without any external influence. In a ferromagnet, the axes about which a majority of the electrons spin are all parallel, but the underlying cause for this alignment is not always clear. A dilute ferromagnetic oxide is an oxide material doped with a small amount of a transition metal, which represents a marriage between magnetic materials and those used in electronics. Crucially, and unlike the ferromagnetic-semiconductors, dilute ferromagnetic oxides remain in a ferromagnetic state at room temperature.

Some materials have ferromagnetic constituents but exhibit no magnetism. However, some ferromagnets consist of substances that, on their own, are nonmagnetic. A full understanding of this enigma is vital for designing efficient spintronic devices and requires determining which electrons, or other type of charge carrier in a material, mediate the ferromagnetism. To resolve this question in dilute ferromagnetic oxides, Ohtsuki and his co-workers examined one commonly used example: cobalt-doped titanium dioxide (Co:TiO2). “Several mechanisms have been suggested for the origin of ferromagnetism in Co:TiO2, but no firm conclusion has been established,” says Ohtsuki.

The researchers used a powerful material characterization technique known as x-ray photoemission spectroscopy. A beam of x-rays, in this case from the SPring-8 synchrotron radiation facility, excited electrons from the sample of Co:TiO2. “The number of excited electrons versus their kinetic energies provided detailed information about the atomic composition and electronic state of the material,” explains Ohtsuki.

Ohtsuki and his team established that ferromagnetism is mediated by the electrons in the third shell—so-called 3d electrons—of the titanium ions (Fig. 1), a mechanism that has never been considered as a possibility by scientists before. The titanium 3d electrons align the spin of the cobalt atoms as they travel through the material.

The team’s discovery enhances the likelihood that dilute ferromagnetic oxides will be used as spintronic devices. “Our results have proven that magnetism and conductivity are correlated in Co:TiO2 thin films,” explains Ohtsuki. “This could make them applicable to magnetic random access memory (MRAM) or spin transistors.”

Source: PhysOrg

In the arid Namib Desert on the west coast of Africa, one type of beetle has found a distinctive way of surviving. When the morning fog rolls in, the Stenocara gracilipes species, also known as the Namib Beetle, collects water droplets on its bumpy back, then lets the moisture roll down into its mouth, allowing it to drink in an area devoid of flowing water.

What nature has developed, Shreerang Chhatre wants to refine, to help the world's poor. Chhatre is an engineer and aspiring entrepreneur at MIT who works on fog harvesting, the deployment of devices that, like the beetle, attract water droplets and corral the runoff. This way, poor villagers could collect clean water near their homes, instead of spending hours carrying water from distant wells or streams. In pursuing the technical and financial sides of his project, Chhatre is simultaneously a doctoral candidate in chemical engineering at MIT; an MBA student at the MIT Sloan School of Management; and a fellow at MIT's Legatum Center for Development and Entrepreneurship.

Access to water is a pressing global issue: the World Health Organization and UNICEF estimate that nearly 900 million people worldwide live without safe drinking water. The burden of finding and transporting that water falls heavily on women and children. "As a middle-class person, I think it's terrible that the poor have to spend hours a day walking just to obtain a basic necessity," Chhatre says.

A fog-harvesting device consists of a fence-like mesh panel, which attracts droplets, connected to receptacles into which water drips. Chhatre has co-authored published papers on the materials used in these devices, and believes he has improved their efficacy. "The technical component of my research is done," Chhatre says. He is pursuing his work at MIT Sloan and the Legatum Center in order to develop a workable business plan for implementing fog-harvesting devices.

Interest in fog harvesting dates to the 1990s, and increased when new research on Stenocara gracilipes made a splash in 2001. A few technologists saw potential in the concept for people. One Canadian charitable organization, FogQuest, has tested projects in Chile and Guatemala.

Chhatre's training as a chemical engineer has focused on the wettability of materials, their tendency to either absorb or repel liquids (think of a duck's feathers, which repel water). A number of MIT faculty have made advances in this area, including Robert Cohen of the Department of Chemical Engineering; Gareth McKinley of the Department of Mechanical Engineering; and Michael Rubner of the Department of Materials Science and Engineering. Chhatre, who also received his master's degree in chemical engineering from MIT in 2009, is co-author, with Cohen and McKinley among other researchers, of three published papers on the kinds of fabrics and coatings that affect wettability.

One basic principle of a good fog-harvesting device is that it must have a combination of surfaces that attract and repel water. For instance, the shell of Stenocara gracilipes has bumps that attract water and troughs that repel it; this way, drops collects on the bumps, then run off through the troughs without being absorbed, so that the water reaches the beetle's mouth.

To build fog-harvesting devices that work on a human scale, Chhatre says, "The idea is to use the design principles we developed and extend them to this problem."

To build larger fog harvesters, researchers generally use mesh, rather than a solid surface like a beetle's shell, because a completely impermeable object creates wind currents that will drag water droplets away from it. In this sense, the beetle's physiology is an inspiration for human fog harvesting, not a template. "We tried to replicate what the beetle has, but found this kind of open permeable surface is better," Chhatre says. "The beetle only needs to drink a few micro-liters of water. We want to capture as large a quantity as possible."

In some field tests, fog harvesters have captured one liter of water (roughly a quart) per one square meter of mesh, per day. Chhatre and his colleagues are conducting laboratory tests to improve the water collection ability of existing meshes.

FogQuest workers say there is more to fog harvesting than technology, however. "You have to get the local community to participate from the beginning," says Melissa Rosato, who served as project manager for a FogQuest program that has installed 36 mesh nets in the mountaintop village of Tojquia, Guatemala, and supplies water for 150 people. "They're the ones who are going to be managing and maintaining the equipment." Because women usually collect water for households, Rosato adds, "If women are not involved, chances of a long-term sustainable project are slim."

Whatever Chhatre's success in the laboratory, he agrees it will not be easy to turn fog-harvesting technology into a viable enterprise. "My consumer has little monetary power," he notes. As part of his Legatum fellowship and Sloan studies, Chhatre is analyzing which groups might use his potential product. Chhatre believes the technology could also work on the rural west coast of India, north of Mumbai, where he grew up.

Another possibility is that environmentally aware communities, schools or businesses in developed countries might try fog harvesting to reduce the amount of energy needed to obtain water. "As the number of people and businesses in the world increases and rainfall stays the same, more people will be looking for alternatives," says Robert Schemenauer, the executive director of FogQuest.

Indeed, the importance of water-supply issues globally is one reason Chhatre was selected for his Legatum fellowship.

"We welcomed Shreerang as a Legatum fellow because it is an important problem to solve," notes Iqbal Z. Quadir, director of the Legatum Center. "About one-third of the planet's water that is not saline happens to be in the air. Collecting water from thin air solves several problems, including transportation. If people do not spend time fetching water, they can be productively employed in other things which gives rise to an ability to pay. Thus, if this technology is sufficiently advanced and a meaningful amount of water can be captured, it could be commercially viable some day."

Quadir also feels that if Chhatre manages to sell a sufficient number of collection devices in the developed world, it could contribute to a reduction in price, making it more viable in poor countries. "The aviation industry in its infancy struggled with balloons, but eventually became a viable global industry," Quadir adds. "Shreerang's project addresses multiple problems at the same time and, after all, the water that fills our rivers and lakes comes from air."

That said, fog harvesting remains in its infancy, technologically and commercially, as Chhatre readily recognizes. "This is still a very open problem," he says. "It's a work in progress."

Source: EurekAlert