www.nature.com/nature Vol 466 | Issue no. 7307 | 5 August 2010 Domestic science Although China is a world leader in renewable-energy technology, it is missing the chance to deploy this equipment on a suitably grand scale at home. he United States’ lengthy reign as the world’s number-one of 500 gigawatts of renewable-energy capacity by 2020 — nearly one- energy consumer came to an end last year, according to the third of the nation’s projected power capacity for that year. TParis-based International Energy Agency on 20 July. But the Yet the reality of China’s sustainable energy falls considerably short agency’s revelation that China had finally taken the top slot swiftly of the promise. For example, the installation of wind turbines con- drew denials from officials in Beijing. tinues to outstrip China’s ability to hook them up to the power grid, China’s protests are perhaps understandable given the huge inter- and the sites chosen are not always where the best winds blow. The national sensitivities over which nations have been — and will be — upshot is that the capacity factor, a measure of a turbine’s efficiency responsible for most carbon emissions. But even if China is not yet and ultimately its profitability, is estimated to be at least 10% lower number one, its population of 1.3 billion and its fast-growing economy in China than in the best countries. mean that it will very soon be consuming far more energy than the There are problems with solar power too. China may be the world’s United States. The only real questions are by how much will that usage leading producer of photovoltaic cells, with more than 40% of the glo- grow, and how much environmental damage will it do in the process? bal market, but it is not even among the top five countries for install- One fact China is not disputing is that it extended its lead in sus- ing those cells domestically. And when the Chinese government and tainable energy last year, adding 37 gigawatts of renewable capacity, utilities do deploy photovoltaics, they prefer big, centralized, easily nearly half of the 80 gigawatts added globally in 2009. That brought its managed installations, which limits a technology that is ideally suited total renewable capacity to 226 gigawatts, dwarfing the 144 gigawatts to broad but small-scale use in places such as farms and villages. China of its nearest rival, the United States (see go.nature.com/vgU3mn). has likewise done little to encourage the use of concentrated solar China’s sustainable future has solid support from the government and thermal energy, a low-tech but effective approach that uses lenses and the industrial and financial sectors. For example, investment in China’s mirrors to focus sunlight to run conventional steam turbines. clean-energy companies by the financial sector hit US$33.7 billion China’s success with wind and solar manufacturing has given it last year — a 53% increase over 2008 and more than the $32.3 billion good credentials in sustainable energy. But its focus on green tech- invested in North and South America combined. And last month, Chi- nologies that are also immediately lucrative for export needs to give na’s National Energy Administration announced a ten-year, 5-trillion- way to a more comprehensive effort to ensure that its ambitious yuan (US$738-billion) plan that will help China realize its stated target investments in domestic green energy are as effective as possible. ■ electric utility companies — not least because many of the utilities are Slow progress keen to end years of regulatory and economic doubt. It is unlikely that the group’s discussions will bear fruit this year, but lawmakers are pay- US cap-and-trade legislation has fallen victim to ing attention. And it is clear that a solid majority of senators has become politics. But all is not lost. convinced that something needs to be done about carbon emissions. Meanwhile, political pressure for action continues to come from s China surges ahead with renewable energy (see above), all for- states, communities, environmentalists and many businesses. And ward motion seems to have stalled in the US Senate. Two weeks everyone on Capitol Hill knows that if Congress fails to move, Presi- Aago, with the November elections in mind and the Republican dent Barack Obama’s administration will regulate industrial green- minority in no mood to compromise, the Senate’s Democratic leaders house-gas emissions using the Environmental Protection Agency’s admitted that they would not have the votes this year to pass any kind existing authority under the Clean Air Act — a process that is the first of cap-and-trade system to curb carbon emissions. Instead, they opted choice of no one, including Obama. for a scaled-back energy bill that addresses issues such as the Gulf of Although the political discussion has stalled at the top, there is Mexico oil spill without doing anything to deal with global warming. reason to believe that momentum is gradually building from below As Nature went to press, it was unclear whether even that bill would — to the extent that at least some Republicans might be more willing pass. And with the midterm election almost certain to shift a substan- to strike a deal next year. They should do so. But if the result is not tial number of seats to the Republicans, who have so far been united in the comprehensive attack on global warming that many had wished their opposition to what they call ‘cap-and-tax’, the prospects for more for, perhaps that is inevitable: with an issue as big and complex as substantive climate legislation next year seem dim. climate change, there may be no way to reach consensus on a single But behind the scenes, an informal group of energy-industry officials piece of legislation that solves every problem for everybody. Instead, and environmentalists is quietly working on a proposal for compro- policy-makers both in the United States and at the international level mise legislation that would impose a cap-and-trade regimen on just the will have to keep putting the solutions together one step at a time. ■ 667 © 2010 Macmillan Publishers Limited. All rights reserved Vol 466|5 August 2010 RESEARCH HIGHLIGHTS S ECOLOGY D WAR Life after logging D D. E D. Proc. R. Soc. B doi:10.1098/rspb.2010.1062 (2010) Take a biodiverse rainforest in Southeast Asia. Log it, let the area regrow, then repeat. What do you have? Not much of ecological value, many scientists would say. As a result, such ‘degraded’ lands have often been turned into oil palm plantations. But David Edwards at the University of Leeds, UK, and his co-workers have now found that such twice-logged forests retain a surprising amount of biodiversity. Using birds and dung beetles as proxies for biodiversity, the researchers surveyed 18 sites in Borneo — some never logged, some logged once, some twice. From their nets, traps and by using binoculars, the authors determined that more than 75% of species found in unlogged forests continued to live in doubly logged forests. BIOTECHNOLOGY report that the neurons release a signalling this structure is curved rather than coiled. molecule to control the formation and Zhe-Xi Luo at the Carnegie Museum of Fuel from microbes maintenance of these ‘tunnels’. Natural History in Pittsburgh, Pennsylvania, Science 329, 559–562 (2010) Kazunobu Sawamoto at Nagoya City and his colleagues suggest that the cochlea Many plants, insects and microbes naturally University in Japan and his colleagues studied was innervated before it evolved into today’s produce small quantities of alkanes and neuronal movement in the brain tissue of curved shape. alkenes — long-chain carbon and hydrogen mice in which the gene for a protein called molecules that are major components of SLIT1 had been deleted. They noticed slowed ASTRONOMY fossil fuels. The biotechnology company LS9, neuronal migration. The team also found based in South San Francisco, California, has that the receptors for SLIT1 were expressed Powerful space lens pinpointed the biochemical pathway that in astrocytes and were also required for Astron. Astrophys. doi:10.1051/0004- bacteria use to do this. proper movement. The interaction of SLIT1 6361/201014376 (2010) Andreas Schirmer and his colleagues with its receptors resulted in a change in the Brighter than a hundred billion stars have discovered and patented two genes in astrocytes’ shape and organization, leading to combined, quasars — extremely energetic cyanobacteria that encode enzymes that faster neuronal migration. galactic nuclei — typically outshine and convert fatty-acid metabolites into fuel- obscure everything in their vicinity. Now grade alkanes and alkenes. They expressed EVOLUTION astronomers have spotted a quasar that acts these genes in the bacterium Escherichia coli, as a gravitational lens, and have used this fed it glucose, and showed that it secreted Ear roots property to uncover information about the diesel-like fuel that did not need any further Proc. R. Soc. B doi:10.1098/rspb.2010.1148 (2010) galaxy that it inhabits. chemical conversions. The company is Some of the best hearing in the animal Malte Tewes at the Swiss Federal Institute currently scaling up this process. kingdom belongs to mammals, of Technology (EPFL) in Lausanne and his including humans and bats, colleagues sifted through more than 22,000 . NEUROSCIENCE C thanks to the snail-shaped potential candidates to find the exotic O S . coiling of the cochlea, a object, which is about 490 megaparsecs R Tunnelling brain cells key part of the inner ear. A away. With its strong gravitational pull, the Neuron 67, 213–223 (2010) 150-million-year-old fossil quasar redirects and magnifies the light Developing neurons must migrate of a mammal, Dryolestes of a galaxy located almost exactly behind BONN)/ NIV.