Archive for December, 2010

Skype says service stabilized

December 25, 2010 Leave a comment

23 December 2010 last updated at 6: 13 pm Skype sign in screen, AFP/Getty Skype was offline for almost two days for some people. Free Internet telephone service Skype says it ‘stabilize’ its service after a two-day outage.

Set in a blog post up too late to 23 December it said handling it 90% of its volume was typical call.

Audio, video and instant messaging systems running over the Skype network normally carried out, it was said.

Skype, said the error by a “software problem” to critical parts of its network was created.

“We take outages like this seriously and apologize for the inconvenience,” said Skype CEO Tony Bates BBC News.

The company said in a blog post that you its paying customers would offer compensation in the form of call credit vouchers.

The only services links for fix were offline instant messaging and video Group calls. He said that problems offline took the service were caused by a malicious attack. It hopes to publish a more detailed explanation in the near future.

Business failure

In a previous post, the company said that the problem is caused by a number of “Supernode” error. This “Act a bit like telephone directories” that said company, transfer traffic between users.

“If you want to talk to someone and can not find your Skype app immediately (for example, because you connect from another location or another device) your computer or phone will first try to find a supernode to figure you out like to achieve,” read it.

“Under normal circumstances, there are available a large number of supernodes.” “Unfortunately, many of you offline due to a problem today were some versions of Skype, taken.”

The company said its engineers tried had to “Supernodes of mega”, to create the problem.

BBC readers Igor Hnatko, who said his company an outsourcing company in Kuala Lumpar, Malaysia, “strongly affected by the failure was”.

“It made me realize how much hold to contact my business as a solution for customers and employees VOIP technology and Skype is,” he said.

“In General, Skype service is of a very high standard, but has not existence.”

He said, “not at all Skype join its employees” have been.

“We do accounting and tax for Australian accounting firms here in Kuala Lumpur, and during this crucial time in advance, we have seen the holidays if our capacity is up 100% Skype collapse, the mildly disappointing is.”

“We have started look at some alternatives, but Skype product is a part of our business for the last five years and having to switch to an alternative provider would be difficult, but we must, as a back-up plan, who after this incident.”

Om Malik, an industry commentator and editor of website, echo his statements.

“Skype is one of the most important applications of the modern Web,” he wrote.

“There is already a hit with consumers, and in the last few years there are part of the economic fabric for startups and small companies around the world.” I’m not sure that we can understand the productivity costs this outage.

“The failure comes at a time, when Skype starts to ask businesses for your business.” If I a big business, be extremely cautious about adopting Skype for business, particularly in the light of this current failure, I would be “Mr Malik added.”

Categories: Technology Tags: , ,

Microsoft warns on IE browser bug

December 25, 2010 Leave a comment

23 December 2010 last updated at 12: 27 pm Screengrab of Internet Explorer homepage, Microsoft Microsoft’s workaround for the IE bug protects all users of your Web browser. Microsoft has a warning about a serious vulnerability in all versions of its Internet Explorer (IE)-browser output.

If exploited from a booby-trapped website bug to allow over an unprotected computer attacker would.

Code that exploit the error has been published already, although Microsoft said it had no evidence to suggest it was currently used by tech criminals.

A workaround for the bug has produced were while Microsoft works on a permanent solution.

Code injection

The bug revolves around the way IE managed during processing of cascading a computer’s memory style sheets – a widely-used technology that defines the look and feel of pages on a site.

Tech criminals a computer have can, process long known that you use IE memory management to inject their own malicious code into the instruction how to use a browser. In this way the criminals can get your own code is executed and the abduction of a PC.

Microsoft has released updates that produced improves memory management but security researchers discovered that such protective systems will not be used when some older parts are called Windows.

In a statement, Microsoft said it was the error “Research” and work on a permanent solution. In the meantime he recommends a protection system that known as the enhanced mitigation experience Toolkit.

Installing and applying the Toolkit requires Windows XP users, update the version of the operating system use. But even if those who do some which gives it on Windows 7 and Vista user is protection not available.

“We are all possible attacks that attempt to use the alleged vulnerability or effect on customers, currently unaware,” said Dave forest Rome, the Director of Microsoft Trustworthy Computing Group, in a statement.

“As vulnerabilities are going this way most serious as allows remote execution of code,” said Rik Ferguson, senior security analyst at trend micro, “which means that the attacker can be executed programs, such as malware, directly on the computer of the victim.”

He added: “it’s very reminiscent of a vulnerability at the same time two years ago, several national Governments against using IE to warn and to an alternative browser, navigate to be asked.”

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Apple prohibits iPhone Wikileaks app

December 25, 2010 Leave a comment

22 December 2010 last updated at 11: 15 pm Wikileaks logo on iPhone material iPhone app free of charge can be accessed from the Wikileaks phone browser Apple offered has confirmed that it removed a Wikileaks iPhone app from your iTunes store.

Wikileaks app was an unofficial paid for download, gave it access of people to free Wikileaks Twitter feed and documents on your site.

It has been removed three days after it was launched on 17 December.

Apple said that the app which had became more than 4,000 downloads before his concluded “violated guidelines for developers”.

“Apps must comply with all local laws and may not individual or targeted group in harms way”, said a spokesman for the company.

Alien interest

The app Russian developer, Igor Barinov said that Apple had told him, two its guidelines specifically injured.

The first personal attacks States: “any app, that is defamatory, offensive, mean spirited or expected to be the targeted individual or group in harms way place is be rejected.”

The second says “apps with all legal requirements comply in any location where it shall be made users”.

“[Apple] said there is no way back for this application,” said Mr Barinov BBC News.

Reducing comes at a time when a number of companies – including Amazon, visa and MasterCard – services – including Web hosting and processing of donations – to Wikileaks removed.

They have on a number of attacks of corporate Web sites and services by a group of activists who invited call themselves anonymous.

Although the Wikileaks app was unofficial, Mr Barinov said that $1 for each $1.99 (£ 1.19) was channeled sales organization.

Mr Barinov said he created the app to support because he was interested in the leaked the organization can be included in documents, “Information about UFOs” Wikileaks.

Wikileaks apps are still available for other phones, such as running Google Android.

All material offered iPhone app by the wikileaks for free over the phone browser and other not Wikileaks applications accessible.

Categories: Technology Tags: , , ,

Web attacks plague rights sites

December 25, 2010 Leave a comment

22 December 2010 last updated at 09: 41 pm Burmese protesters, AFP/Getty many protest groups are from Web attacks that effectively, haunted says silence human rights research groups and activists are started by huge web attacks by their views, finds research opponents hit hard.

Many Web-based campaign groups knocked offline for weeks by the attacks is who found it.

The researchers expect to increase the pace of attacks such as the tools and techniques be disseminated.

It calls to avoid human rights groups and independent media groups beef up your body’s defences victims.

Flash flood

Research where tried Berkman Center for Internet and society at Harvard University, a feeling how often human rights groups receive the and distributed denial of service (DDoS) attacks is known defeated independent media organizations through what.

DDoS attacks try to a Web site offline tap of overwhelming it with data.

In the 12 months between August 2009 and September 2010, the research found references to 140 attacks against more than 280 different websites. The report confirms that these were probably the most high-profile attacks and that more likely unreported went many.

“These attacks do seem to be increasing,” said Ethan Zuckerman, one of the authors of the report.

While some attacks were triggered by certain events such as elections, others had no obvious cause, he said.

The main story A distributed denial of service (DDoS) attack aims the sites InaccessibleThe attackers often use networks of compromised computers make next – known read a bot that you control the AttacksBy starting overwhelming the target site with requests, the attacker can ensure real visitors can the site thesis requirements look not as real Web traffic so hard to OutTypically filters can reach, these attacks have been aimed high profile sites such as those include government agencies, banks and political OrganisationsThe report a sustainable DDoS attack on Novaya Gazeta, the site of Russia’s most liberal independent newspaper cited.

Deputy executive editor Sergey Sokolov is unsure, who his site but suspect attacked government-funded Kremlin youth organisations.

The report notes that DDoS is used increasingly as a political tool and as a form of protest.

Recruit attacks of participants in so-called voluntary DDoS are popular prove.

The report gives the example of the organization ‘ help Israel win a software package or Patriot DDos, on their computers so that the machine could be used would invited to install individuals recently attacks which editors are in Palestinian objectives.

The most recent example of a voluntary DDoS comes by anonymous, a loose-knit group of activists who uses the method to launch attacks on the websites of the companies it perceived anti Wikileaks.

DDoS attacks take small groups of media could and difficult because the organizations have such limited resources, Mr Zuckerman said activists.

“If you are a human rights organization or independent media organization you may £ 20 per month include an account you paying for and its very difficult use at this level of hosting to DDoS prevent,” he told the BBC.

The attacks have not renewed he said will cause real problems for small campaigning groups.

“You have just it do long enough to annoy your ISP and you will kick-off and then at another place host, you will find”, said Mr Zuckerman. Simple tools

The work of some groups appears only on the Web, said Mr Zuckerman, so offline effectively tapping the activists to silence. It takes a long time for some finding a new host, content and build a Web site again.

He said: “We see sites that are not for two or three weeks back online.”

The report also found that DDoS attacks are often the most visible part of a much larger attack on a site or group.

“It is a very good chance if you experience DDoS filter you get targeted E-mail to your system or your passwords to snatch sent,” he said.

Mr Zuckerman said some report logged hundreds or thousands of PCs in a botnet DDoS attacks used – networks of hijacked computers – but others had just as big an effect with far fewer resources.

“There are certain attacks that seem to work if you have only one or two machines,” he said.

What can cause problems in the future he suggested would be easy to use tools such as the employees of anonymous activists support the Wikileaks.

“It seems like DDoS has become easier for more people to engage in,” he said. “The threats to do seem to be increasing.”

In response he said rights required groups work too hard to understand the threats and preparation in the event that you have been taken.

“This community needs to much smarter to get much much kenntnisreicher”, he said.

Categories: Technology Tags: , , ,

Cull ‘will not halt bat killer’

December 25, 2010 Leave a comment

24 December 2010 Last updated at 09:51 GMT By Mark Kinver Science and environment reporter, BBC News Group of little brown bats displaying symptoms of WNS (Nancy Heaslip/New York Department of Environmental Conservation) A study has warned that if WNS continues unabated, there is a danger that species will be wiped out in less than two decades Culling will not halt the spread of a disease that has killed a million bats in the US since 2006, a study says.

Researchers reached their conclusion by modelling how white-nose syndrome (WNS) is passed from bat to bat.

Writing in Conservation Biology, they add that a cull would not work because the source of the fungal pathogen is believed to occur in the environment.

Earlier studies have warned that WNS could wipe out bat populations in the north-east of the US within 20 years.

Carrying out a cull of bats in areas where the disease is known to be present is one of the options available in an attempt to contain the spread of the killer fungus.

Continue reading the main story Little brown bat displaying symptoms of WNS (Ryan von Linden/New York Department of Environmental Conservation) WNS is associated with a fungus known as Geomyces destructansOnce present in a colony, WNS can wipe out the entire populationIt was first reported in a cave in New York in February 2006The most common visible symptom of an infected bat is a white fungus on the animal’s nose, but it can also appear on its wings, ears or tailOther symptoms include weight loss and abnormal behaviour, such as flying in daylight or sub-zero temperaturesSpecies known to be vulnerable to WNS include: tri-coloured, little brown, big brown, northern long-eared, small-footed and Indiana batsThere is no known risk to human health

(Source: US Fish & Wildlife Service)

“We developed a model taking into account the complexity of the bat life history, looking at the roosts and the areas where there are large contacts between the bats,” said co-author Thomas Hallam from the Department of Ecology and Evolutionary Biology at the University of Tennessee.

“Given the dispersal aspect of the problem and the complexity of hibernating bat ecology, it was a case that these things together certainly meant that culling would not work in the case of bats.”

WNS, described by some as the worst wildlife health crisis in the US in living memory, is named after a white fungus that appears on the muzzle and/or wings of infected animals.

However, bats with WNS do not always have the characteristic visual symptoms, but may display abnormal behaviour around their hibernacula (caves and mines where bats hibernate during winter months).

These behaviours include flying outside during the day (when their insect prey is not available) in sub-zero temperatures, or clustering near the entrance to the hibernaculum.

Professor Hallam explained that there was a high degree of bat-to-bat interaction, which has been identified as the main way the disease is transmitted, during the course of a year.

In autumn, the mating season brings together large numbers of males and females.

This occurs shortly before colonies enter hibernacula, some of which are large enough to house in the region of half-a-million bats.

In the spring, females head to a maternity roost to have their young. Again, this brings bats into contact with members of different colonies.

Since WNS was first recorded in February 2006 in a commercial cave in New York, it has spread to at least 14 states. Cases have also been recorded in a number of Canadian provinces.

Researchers say the fungus associated with the disease, Geomyces destructans, thrives in the dark, damp conditions – such as caves and mines.

Out of control

In their paper, Professor Hallam and co-author Gary McCracken write: “Because the disease is highly virulent, our model results support the hypothesis that transmission occurs in all contact arenas.”

They add: “Our simulations indicated culling will not control WNS in bats primarily because contact rates are high among colonial bats, contact occurs in multiple arenas, and periodic movement between arenas occurs.”

Jeremy Coleman, the national white-nose syndrome co-ordinator for the US Fish and Wildlife Service (FWS), said that culling was a potential tool available to agencies attempting to curb the spread of the disease.

“The spread has been very rapid and very alarming,” he told BBC News.

“The initial comment that spawned all of the ideas of culling was that if we had known what would happen, then we would have gone in and killed every bat and we would not be facing this problem.

“That had a real resonance among researchers and land managers,” Dr Coleman recalled. But he added: “Most people, I would say, feel it is too late for any culling to be effective.”

He explained that the final decision on whether to cull would rest with state or federal agencies.

It is believed that the fungus associated with WNS arrived in the US after it was somehow transported from Europe or possibly Asia.

Map showing the 14 affected states in the US (Image: BBC) To date, 14 states have recorded cases of white-nose syndrome and the fungus

“It was possibly brought over via ‘human-assisted spread’ of some sort – like on somebody’s boots,” Dr Coleman suggested.

“Another possibility is that a bat was somehow transported to North America, perhaps by a cargo plane or freight container, and mixed with bats in New York State.”

A team of European researchers followed up unconfirmed reports in Europe that bats had white fungal growths appearing to match the symptoms of WNS.

In a paper in the Emerging Infectious Diseases journal, they suggested that the Geomyces destructans fungus was present throughout Europe.

However, they added, it seemed as if species of bats in Europe were possibly more immunologically or behaviourally resistant to the fungus than North American species, as it did not increase mortality.

No magic bullet

European bats may be resistant to the disease because they are generally bigger than comparable species in the US. Also, European colonies tend to be not as large as ones found on the other side of the Atlantic.

“What we hope to learn, through genetic means, is the similarities and differences between the North American strains and the European strains,” explained Dr Coleman, who is overseeing the formation of a national management plan that hopes to bring together the efforts of state and federal agencies under one umbrella.

US researchers based at MIT recently sequenced the genome of the US strain of G. destructans and made the data publicly available in a hope that it would “jumpstart work on this problem, to help devise ways to track and combat this fungus”.

“There are a lot of questions where some answers could potentially could give us some hope,” observed Dr Coleman.

Professor Hallam said it was difficult to know if anything could be done to prevent the current outbreak from spreading further and wiping out millions more US bats.

“We have a lot of chemical agents that will get rid of the fungus,” he told BBC News.

“The difficulty is the complexity of bats’ life histories; it is almost impossible to treat enough bats to make it worthwhile.

“I don’t see any easy solution on the horizon.”


Categories: Science Tags:

Obama to regulate refinery gases

December 25, 2010 Leave a comment


23 December 2010 Last updated at 18:06 GMT An oil refinery in California Mr Obama is pushing the EPA to cut greenhouse gas emissions after a climate bill failed earlier this year The Obama administration has said it will regulate greenhouse gas emissions from power plants amid opposition from industry and Republicans in Congress.

The Environmental Protection Agency (EPA) said it would regulate emissions from fossil fuel power plants by 2011 and petroleum refineries by 2012.

President Barack Obama is pushing the EPA to cut emissions after a climate bill failed in Congress this year.

But Republican lawmakers have said the EPA’s new rules will harm the economy.

The EPA said it would propose figures for emissions cuts in 2011 and finalise them in 2012.

The new rules are expected to limit the amount of carbon dioxide a plant can emit per each megawatt hour of electricity produced.

“We are following through on our commitment to proceed in a measured and careful way to reduce greenhouse gas pollution that threatens the health and welfare of Americans and contributes to climate change,” EPA chief Lisa Jackson said in a statement.

Collectively, fossil fuel power plants and petroleum refineries release nearly 40% of the total greenhouse gases emitted in the US.

Republican objections

Republicans, who will take control of the House of Representatives when the new Congress convenes on 5 January, have already expressed opposition to the new regulations.

“I think we ought to start with a two-year pause” in upcoming EPA regulations, said Republican Representative Mike Simpson, who is expected to lead a House panel that controls the EPA’s budget.

Mr Obama said last year that the US would curb emissions by 17% by 2020 compared with 2005 levels.

Legislation forcing reductions in carbon dioxide and other greenhouse gas emissions, which are believed by most climate scientists to contribute to global warming, was struck down in Congress this summer.

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Solar plane’s records confirmed

December 25, 2010 Leave a comment

24 December 2010 Last updated at 11:22 GMT Zephyr at launch The 50kg Zephyr is launched by hand The UK-built solar-powered Zephyr aeroplane has been confirmed as a record-breaker following its non-stop two-week flight earlier this year.

The world governing body for air sports records, the Federation Aeronautique Internationale (FAI), gave Zephyr three records including longest time aloft.

Built by defence technology company Qinetiq, the craft completed its two-week flight in the US in July.

The company sees applications in surveillance and communications.

The July feat led to Zephyr being dubbed the “eternal plane”.

“This aircraft can help track pirates off the Horn of Africa, alert the authorities about where and how fast forest fires are spreading, and ensure that soldiers’ communications remain unaffected when fighting in mountainous or hilly terrain,” said Qinetiq’s chief designer Chris Kelleher.

The FAI noted that Zephyr smashed the previous record for the absolute duration of an unmanned autonomous vehicle (UAV) flight – set by Northrop Grumman’s Global Hawk in 2001 – by a factor of 11.

The organisation set the official duration at 336 hours, 22 minutes and eight seconds.

Zephyr’s flight also set a new mark for flight duration for a UAV of its class – unmanned craft weighing 50-500kg – and, for that class, the altitude record of 21,562m (70,741ft).

Wing-to-tail guide to a prototype of the ‘eternal’ plane

Launched by hand, the aircraft flies during daytime on electricity generated by photovoltaic arrays – solar panels – on its wings.

Made of amorphous silicon, the arrays are about as thick as a sheet of paper. They also charge lithium-sulphur batteries that power the craft by night.

During the flight in July, engineers found that Zephyr lost some altitude during the night as power to the engines reduced – but the batteries stored enough to keep the craft aloft.

Key to its success is the ultra-light design, based on carbon fibre, which means that with a wingspan of 22.5m (74ft) it weighs little more than 50kg (110 lb).

Solar-powered high-altitude long-endurance (Hale) UAVs are expected to have a wide range of applications.

The military will want to use them as reconnaissance and communications platforms. Civilian and scientific programmes will equip them with small payloads for Earth observation duties.

Their unique selling point is their persistence over a location. Low-Earth orbiting satellites come and go in a swift pass overhead, and the bigger drones now operated by the military still need to return to base at regular intervals for refuelling.


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Russian tiger team hails success

December 24, 2010 Leave a comment

By Victoria Gill
Science and nature reporter, BBC News
Amur tiger (Image: John Goodrich/WCS) Critically endangered Amur tigers occasionally wander into remote villages
Living within the habitat of a dangerous animal is not easy.

But it is particularly challenging when that animal is the critically endangered Amur tiger.

If a tiger wanders into a remote Russian village it poses a threat, but also raises a difficult quandary: how can people protect themselves without resorting to killing a creature that is on very the brink of extinction?

A special Tiger Response Team in Russia has sought to solve that problem.

The World Conservation Society (WCS) and an anti-poaching patrol dubbed Inspection Tiger are working closely with the team.

It was set up by the government in 1999 to help resolve “human- tiger conflict”.

Amur tigers live in the mosaic of forests in Russia’s Far East – an expanse of more than 150,000 sq km of tiger habitat that is dotted with small human settlements.

“There’s a grey area where both tigers and humans co-exist,” explains Dale Miquelle, director of the WCS Russia Programme.

“So, even though the tigers are incredibly scarce, they do pass through or close to villages on a regular basis.”

When a tiger does come too close, it might prey on a domestic animal – most commonly a pet dog or a cow.

Much more rarely it might attack a human.

Danger signal

In the past 10 years, Amur tigers have killed at least 254 domestic animals, 160 of which were dogs.

Official records show 19 attacks on humans, resulting in 11 injuries and two deaths.

And this is where the response team’s very hands-on approach comes in.

When someone sees a tiger or discovers an animal that has clearly been mauled by one, they can alert the local authorities, who then contact the team.

“The local authorities assess the situation and, if necessary, a team is despatched,” explained Dr Miquelle.

“But we’re dealing with a vast area, so it can take several days to reach the village.”

Once there, the response team has a number of options.

The most straightforward is to scare the tiger away, using rockets or flares. But sometimes it is necessary to capture the animal.

“We do that quite often,” says Dr Miquelle. “What we do once we capture it depends on the situation.

“Sometimes we’ll put a radio collar on it and put it back where it is.

“Sometimes we’ll move it to another location – if we think that will reduce the likelihood of it [returning to the village].”

But if a tiger is wounded, the situation is more complicated.

Amur tiger being fitted with a radio collar (Image: John Goodrich/WCS) Radio collars allow conservationists to track the critically endangered tigers

John Goodrich, a conservationist and wildlife photographer, has worked with the team during some of their tiger rescue missions.

He says most tigers that attack people in Russia have been shot by poachers or injured by traps.

And these injuries change the tigers’ behaviour – driving the animals into human populations to pick on domesticated prey, if they are incapacitated and unable to hunt.

According to Dr Goodrich, wounds from from botched poaching attempts are a leading cause of Amur tiger attacks on people.

Tiger rehabilitation

Injured tigers can sometimes be rehabilitated and released into the forest.

But when one is too badly hurt or too dangerous, the team has to remove it from the wild altogether – for its own safety, as well as to protect humans.

Dr Goodrich followed the rehabilitation of one young male tiger called Volya, which was shot in the face by poachers.

“The bullet broke three canines and shattered his lower jaw,” he recalled.

Vets at the Utyos Wildlife Rehabilitation Center wired it together as best they could: “But the injury condemned Volya to a life in captivity”.

Dr Goodrich and his colleagues are now attempting to survey the prevalence of infectious diseases in the Amur tiger population, which might also affect their behaviour and make them more aggressive to humans.

Counting tigers

Amur tiger at the Utyos Wildlife Rehabilitation Center (Image: John Goodrich/WCS) The team sometimes transports injured tigers to a wildlife rehabilitation centre

It is tricky to quantify exactly how many tigers the team’s efforts have saved; but at this stage, every individual counts.

The latest survey estimated that there were just 350 Amur tigers remaining in the wild.

“There’s some indication that we’ve been able to reduce the number of tiger losses associated with conflicts,” said Dr Miquelle.

He says there is definitely room for improvement. Efforts to scare animals away from human-dominated areas have not been as successful as hoped.

“But with so few tigers remaining, we know we have to turn that declining trend around,” he tells BBC News.

“And we do see human caused mortality as a really important component of that – 20 years ago, the main intervention was a bullet.”

In such isolated communities, the response team hopes to give local people a signal that there is a group that cares about their welfare.

“It really can be extremely threatening when an animal the size of a tiger walks into you neighbourhood,” says Dr Miquelle.

“So having a team that can deal with that is really important.”


Categories: Nature Tags: , , ,

New solar fuel machine unveiled

December 24, 2010 Leave a comment

23 December 2010 Last updated at 19:11 GMT By Neil Bowdler Science reporter, BBC News In the prototype, sunlight heats a ceria cylinder which breaks down water or carbon dioxide In the prototype, sunlight heats a ceria cylinder which breaks down water or carbon dioxide A prototype solar device has been unveiled which mimics plant life, turning the Sun’s energy into fuel.

The machine uses the Sun’s rays and a metal oxide called ceria to break down carbon dioxide or water into fuels which can be stored and transported.

Conventional photovoltaic panels must use the electricity they generate in situ, and cannot deliver power at night.

Details are published in the journal Science.

The prototype, which was devised by researchers in the US and Switzerland, uses a quartz window and cavity to concentrate sunlight into a cylinder lined with cerium oxide, also known as ceria.

Ceria has a natural propensity to exhale oxygen as it heats up and inhale it as it cools down.

If as in the prototype, carbon dioxide and/or water are pumped into the vessel, the ceria will rapidly strip the oxygen from them as it cools, creating hydrogen and/or carbon monoxide.

Hydrogen produced could be used to fuel hydrogen fuel cells in cars, for example, while a combination of hydrogen and carbon monoxide can be used to create “syngas” for fuel.

It is this harnessing of ceria’s properties in the solar reactor which represents the major breakthrough, say the inventors of the device. They also say the metal is readily available, being the most abundant of the “rare-earth” metals.

Methane can be produced using the same machine, they say.

Refinements needed

The prototype is grossly inefficient, the fuel created harnessing only between 0.7% and 0.8% of the solar energy taken into the vessel.

Most of the energy is lost through heat loss through the reactor’s wall or through the re-radiation of sunlight back through the device’s aperture.

But the researchers are confident that efficiency rates of up to 19% can be achieved through better insulation and smaller apertures. Such efficiency rates, they say, could make for a viable commercial device.

“The chemistry of the material is really well suited to this process,” says Professor Sossina Haile of the California Institute of Technology (Caltech). “This is the first demonstration of doing the full shebang, running it under (light) photons in a reactor.”

She says the reactor could be used to create transportation fuels or be adopted in large-scale energy plants, where solar-sourced power could be available throughout the day and night.

However, she admits the fate of this and other devices in development is tied to whether states adopt a low-carbon policy.

“It’s very much tied to policy. If we had a carbon policy, something like this would move forward a lot more quickly,” she told the BBC.

It has been suggested that the device mimics plants, which also use carbon dioxide, water and sunlight to create energy as part of the process of photosynthesis. But Professor Haile thinks the analogy is over-simplistic.

“Yes, the reactor takes in sunlight, we take in carbon dioxide and water and we produce a chemical compound, so in the most generic sense there are these similarities, but I think that’s pretty much where the analogy ends.”

The PS10 solar tower plant near Seville, Spain. Mirrors concentrate the sun's power on to a central tower, driving a steam turbine The PS10 solar tower plant near Seville, Spain. Mirrors concentrate the sun’s power on to a central tower, driving a steam turbine

Daniel Davies, chief technology officer at the British photovoltaic company Solar Century, said the research was “very exciting”.

“I guess the question is where you locate it – would you put your solar collector on a roof or would it be better off as a big industrial concern in the Sahara and then shipping the liquid fuel?” he said.

Solar technology is moving forward apace but the overriding challenges remain ones of efficiency, economy and storage.

New-generation “solar tower” plants have been built in Spain and the United States which use an array of mirrors to concentrate sunlight onto tower-mounted receivers which drive steam turbines.

A new Spanish project will use molten salts to store heat from the Sun for up to 15 hours, so that the plant could potentially operate through the night.


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