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| SCIENCE & TECHNOLOGY |
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Breakthrough
in green tech to extract hydrogen from water Climate
scientists struggle to explain slowdown in warming New
micro-batteries can jump-start a car Trends |
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Breakthrough in green tech to extract hydrogen from water
SCIENTISTS have harnessed the principles of photosynthesis to develop a new way of producing hydrogen — in a breakthrough that offers a possible solution to global energy problems. The researchers claim the development could help unlock the potential of hydrogen as a clean, cheap and reliable power source. Unlike fossil fuels, hydrogen can be burned to produce energy without producing emissions. It is also the most abundant element on the planet. Hydrogen gas is produced by splitting water into its constituent elements — hydrogen and oxygen. But scientists have been struggling for decades to find a way of extracting these elements at different times, which would make the process more energy-efficient and reduce the risk of dangerous explosions. In a paper published in the journal Nature Chemistry, scientists at the University of Glasgow outline how they have managed to replicate the way plants use the sun’s energy to split water molecules into hydrogen and oxygen at separate times and at separate physical locations. Experts heralded the “important” discovery, saying it could make hydrogen a more practicable source of green energy. Professor Xile Hu, director of the Laboratory of Inorganic Synthesis and Catalysis at the Swiss Federal Institute of Technology in Lausanne, said: “This work provides an important demonstration of the principle of separating hydrogen and oxygen production in electrolysis and is very original. Of course, further developments are needed to improve the capacity of the system, energy efficiency, lifetime and so on. But this research already offers potential and promise and can help in making the storage of green energy cheaper.” Until now, scientists have separated hydrogen and oxygen atoms using electrolysis, which involves running electricity through water. This is energy-intensive and potentially explosive, because the oxygen and hydrogen are removed at the same time. But in the new variation of electrolysis developed at the University of Glasgow, hydrogen and oxygen are produced from the water at different times, thanks to what researchers call an “electron-coupled proton buffer”. This acts to collect and store hydrogen while the current runs through the water, meaning that in the first instance only oxygen is released. The hydrogen can then be released when convenient. Because pure hydrogen does not occur naturally, it takes energy to make it. This new version of electrolysis takes longer, but is safer and uses less energy per minute, making it easier to rely on renewable energy sources for the electricity needed to separate the atoms. Dr Mark Symes, the report’s co-author, said: “What we have developed is a system for producing hydrogen on an industrial scale much more cheaply and safely than is currently possible. Currently much of the industrial production of hydrogen relies on reformation of fossil fuels, but if the electricity is provided via solar, wind or wave sources we can create an almost totally clean source of power.” Professor Lee Cronin, the other author of the research, said: “The existing gas infrastructure which brings gas to homes across the country could just as easily carry hydrogen as it currently does methane. If we were to use renewable power to generate hydrogen using the cheaper, more efficient decoupled process we’ve created, the country could switch to hydrogen to generate our electrical power at home. It would also allow us to significantly reduce the country’s carbon footprint.” Nathan Lewis, a chemistry professor at the California Institute of Technology and a green energy expert, said: “This seems like an interesting scientific demonstration that may possibly address one of the problems involved with water electrolysis, which remains a relatively expensive method of producing hydrogen.” — The Independent
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Climate scientists struggle to explain slowdown in warming Scientists are struggling to explain a slowdown in climate change that has exposed gaps in their understanding and defies a rise in global greenhouse gasemissions. Often focused on century-long trends, most climate models failed to predict that the temperature rise would slow, starting around 2000. Scientists are now intent on figuring out the causes and determining whether the respite will be brief or amore lasting phenomenon. Getting this right is essential for the short and long-term planning of governments and businesses ranging from energy to construction, from agriculture to insurance. Many scientists say they expect a revival of warming in coming years. Theories for the pause include that deep oceans have taken up more heat with the result that the surface is cooler than expected, that industrial pollution in Asia or clouds are blocking the sun, or that greenhouse gases trap less heat than previously believed. The change may be a result of an observed decline in heat-trapping water vapour in the high atmosphere, for unknown reasons. It could be a combination of factors or some as yet unknown natural variations, scientists say. Weak economic growth and the pause in warming is undermining governments’ willingness to make a rapid billion-dollar shift from fossil fuels. Almost 200 governments have agreed to workout a plan by the end of 2015 to combat global warming. “The climate system is not quite so simple as peoplethought,” said Bjorn Lomborg, a Danish statistician and author of “The Skeptical Environmentalist” who estimates that moderate warming will be beneficial for crop growth and human health. Some experts say their trust in climate science has declined because of the many uncertainties. The UN’s Intergovernmental Panel on Climate Change had to correct a 2007 report that exaggerated the pace of melt of the Himalayan glaciers and wrongly said they could all vanish by 2035. “My own confidence in the data has gone down in the past five years,” said Richard Tol, an expert in climate change and professor of economics at the University of Sussex in England. Swedish chemist Svante Arrhenius first showed in 1890 that the man-made carbon dioxide, from coal for instance, traps heat in the atmosphere. Many of the exact effects are still unknown. Greenhouse gas emissions have hit repeated record highs with annual growth of about 3 per cent in most of the decade to 2010, partly powered by rises in China and India. World emissions were75 per cent higher in 2010 than in 1970, UN data show. — Reuters
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New micro-batteries can jump-start a car SMALL in size, big on power! Researchers claim to have developed the world’s most powerful batteries that can jump-start a dead car and recharge your phone in the blink of an eye. The micro-batteries are only a few millimetres in size, yet they pack such a punch that a driver could use a cell phone powered by these batteries to recharge a dead car battery. Developed by researchers at the University of Illinois at Urbana-Champaign, the new micro-batteries out-power even the best super capacitors and could drive new applications in radio communications and compact electronics. “This is a whole new way to think about batteries. A battery can deliver far more power than anybody ever thought,” William P. King, the Bliss professor of mechanical science and engineering, said. “In recent decades, electronics have gotten small. The thinking parts of computers have gotten small. And the battery has lagged far behind. This is a microtechnology that could change all of that,” he said in the study published in the journal Nature Communications. With currently available power sources, users have had to choose between power and energy. For applications that need a lot of power, like broadcasting a radio signal over a long distance, capacitors can release energy very quickly but can only store a small amount. The new micro-batteries offer both power and energy, and by tweaking the structure a bit, the researchers can tune them over a wide range on the power-versus-energy scale. The batteries owe their high performance to their internal three-dimensional micro-structure. Building on a novel fast-charging cathode design by materials science and engineering Professor Paul Braun’s group, researchers developed a matching anode and then developed a new way to integrate the two components at the microscale to make a complete battery with superior performance. — PTI
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Trends JOHANNESBURG: A two million-year-old ancestor of man had a mixture of ape and human-like features that allowed it to hike vast distances on two legs with as much ease as it could scurry up trees, according to research. Discovered in a cave near Johannesburg in 2008, the fossils of a species named "Australopithecus sediba" have given researchers clues about the evolution of man and which traits in our ancestors fell by the wayside. An Orthodox Jewish man stands next to giant globes displayed outside the walls of Jerusalem’s Old City on Wednesday. The globes exhibit, an initiative of the non-profit organisation Cool Globes which aims to raise awareness of climate change, will be on display through the summer. — Reuters photo Fish survive 5,000-mile trip across Pacific in tsunami boat SEATTLE: Scientists are baffled as to how a group of small fish native to Japan survived a journey across the Pacific after they were found on a boat swept away by the 2011 tsunami and washed up last month on the coast of Washington state. The batch of striped beak fish — five in all — were discovered submerged in the hold of the 20-foot-long fishing skiff, dubbed the Sai-shou-maru, on Long Beach in southwestern Washington.
Scientists find Antarctic ice is melting faster CANBERRA: The summer ice melt in parts of Antarctica is at its highest level in 1,000 years, Australian and British researchers reported, adding new evidence of the impact of global warming on sensitive Antarctic glaciers and ice shelves. Researchers from the Australian National University and the British Antarctic Survey found data taken from an ice core also shows the summer ice melt has been 10 times more intense over the past 50 years compared with 600 years ago. — Reuters |
Fish
survive 5,000-mile trip across Pacific in tsunami boat
