Hybrid power plants running on sun power

The success of hybrid cars is inspiring yet another way of going green but on a more ambitious scale harnessing solar energy to drive hybrid power plants under an India-Israel project. Avi Kribus, Professor of Mechanical Engineering at Tel Aviv University in Israel, inked the project with S Iniyan, Professor and Director, Institute of Energy Studies, Anna University, Chennai, in October last year to study how solar energy can augment power output. This collaboration is the outcome of a call for proposals for developing alternative energy sources by the Indian government’s department of science and technology and is funded by both the countries. “Sunlight can provide power and heat in amounts far surpassing all of humanity’s needs, but the prohibitively high production cost limits its use worldwide,” Iniyan told IANS . Production of solar-powered electricity “is still two to three times costlier than with fossil fuels,” said Iniyan. “This cost can be brought (down) to competitive levels if the conversion efficiency from sunlight to electricity is boosted and made available in a reliable way,” he added. In this context, the solar- powered steam injected gas turbine (STIG), a technology developed by Kribus, works with much lower steam pressures and temperatures than those required by conventional coal-fired plants. The proposed STIG cycle, which permits the solar part to use cheaper metals and low-cost solar collectors, can cut fossil fuel use by 25 to 50 per cent, bringing down production costs. It will drive hybrid power plants of tomorrow, which will be as competitive as coal-fired ones, according to Iniyan. Kribus explained, “We combine a gas turbine, which works on hot air, and not steam, and inject the solar-produced steam into the process.” “We still need to burn fuel to heat the air, but we add steam from low-temperature solar energy, approximately 200 degrees centigrade,” he added.

World peaks lost no ice in 10 years

The world’s greatest snow-capped peaks, which run in a chain from the Himalayas to Tian Shan on the border of China and Kyrgyzstan, have lost no ice over the last decade, new research shows. The discovery has stunned scientists, who had believed that around 50bn tonnes of melt water were being shed each year and not being replaced by new snowfall. The study is the first to survey all the world’s icecaps and glaciers and was made possible by the use of satellite data. Overall, the contribution of melting ice outside the two largest caps Greenland and Antarctica is much less than previously estimated, with the lack of ice loss in the Himalayas and the other high peaks of Asia responsible for most of the discrepancy.

Bristol University glaciologist Prof Jonathan Bamber, who was not part of the research team, said, “The very unexpected result was the negligible mass loss from high mountain Asia, which is not significantly different from zero.” The melting of Himalayan glaciers caused controversy in 2009 when a report from the UN’s Intergovernmental Panel on Climate Change mistakenly stated that they would disappear by 2035, instead of 2350. However, the scientist who led the new work is clear that while greater uncertainty has been discovered in Asia’s highest mountains, the melting of ice caps and glaciers around the world remains a serious concern. “Our results and those of everyone else show we are losing a huge amount of water into the oceans every year,” said Prof John Wahr of the University of Colorado.

His team’s study, concludes that between 443- 629bn tonnes of melt water overall are added to the world’s oceans each year. This is raising sea level by about 1.5mm a year, the team reports. The scientists are careful to point out that lower-altitude glacier in the Asian mountain ranges sometimes dubbed the “third pole” are definitely melting. Satellite images and reports confirm this. But over the study period from 2003- 10, enough ice was added to the peaks to compensate. The impact on predictions for future sea level rise is yet to be fully studied but Bamber said, “The projections for sea level rise by 2100 will not change by much, say five cm or so, so we are talking about a very small modification.” Existing estimates range from 30cm to one m. Wahr warned that while crucial to a better understanding of ice melting, the eight years of data is a relatively short time period and that variable monsoons mean year-to-year changes in ice mass of hundreds of billions of tonnes. “It is awfully dangerous to take an eight-year record and predict even the next eight years, let alone the next century,” he said.

Biggest tree in danger

The world’s biggest and most magnificent trees face a dire future, thanks to logging, deforestation, pest invasions and effects of climate change. William Laurance, Professor at James Cook University, warned that their demise will have substantial impact on bio diversity and forest ecology and worsen climate change too. Reviewing research from forests around the world, Laurance wrote in the New Scientist magazine that “big trees need a safe place to live and long periods of stability. But time and stability are becoming very rare commodities in our modern world”.

Giant trees offer critical habitat and forage for wildlife, while transpiring massive amounts of water through their leaves contributing to local rainfall. Old trees also lock up massive amounts of carbon. “But their ability to sequester carbon and render other ecosystem services is threatened by human activities. Some of the world’s largest trees are particularly targeted by loggers. “The oldest trees are among the most valuable and therefore the first to be cut in ‘virgin’ forest areas,” he said, according to a university statement. “Big trees are also sensitive to habitat fragmentation, which exposes them to stronger winds and drier conditions,” he said.

Green Dating sites

For the environmentally conscious soul in search of romance, here are reviews of some of the most popular online sites aimed at the green heart

Green friends: Claiming to be ‘the world’s first, largest and most effective site for singles green_datinginterested in vegetarianism or environmental protection’, Green Friends’ database is searchable only after joining. Membership appears small, but the site offers many features: sending a ‘wink’, blogs, greeting cards, forums, and linking to other friends in Facebook, MySpace and other community sites.

Green singles: Launched by a sweet looking couple in the 1980s first as a newsletter, then blossoming into a website, Green Singles boasts more than 15,000 members and success stories from recently married couples to punk rock teenagers enjoying their first experience of love.

Concerned singles: Launched in 1984, the site is home to mostly 50+ straight women interested in nature and meditation. Most are from America, but a few reside in other countries. If you’re a man looking for a female hiking enthusiast over 50, this site is where you should start.

Eco dater: A young but enthusiastic site, Eco Dater currently offers its premium membership free. This provides advanced search options and allows unlimited photos, along with its standard membership features of contacting other free members and contributing to the site’s blog. While the membership is relatively small, its pleasant interface, friendly attitude and encouragement of user feedback should quickly draw more users.