REACT now

Miniaturizing Solar Panel

2009-07-02T10:18:00.001-07:00

PHOTOVOLTAIC cells are already a familiar sight on rooftops. But one day, miniature cells may also be found in more unconventional places: power-generating windows, car sunroofs or a T-shirt. John A. Rogers, a professor of materials science and engineering at the University of Illinois, Urbana-Champaign, and his team have figured out a new way to define solar energy.They have successfully printed out solar cells on plastic rolls and have made them a tenth of the size of conventional semiconductor cells. This is a groundbreaking discovery and may lead to becoming a major game changer for the solar industry since the material is flexible, cheap and can be applied to almost anything as you can see in the photo below.Dr. Rogers “has figured out how to grab thin layers of silicon or other inorganics, and put them on whatever substrates you want,” Dr. Javey said. Traditional silicon solar cells are rigid, heavy and opaque, but they dominate the technology because they are very reliable and efficient, he said, and because silicon is abundant. Still, the brittleness of silicon limits its uses. Dr. Rogers has figured out how to grab thin layers of silicon or other inorganics, and put them on whatever substrates you want. According to the NY Times interview, Dr. Rogers said he was pleased with the new cells’ flexibility and thinness but said that they offered another even more critical advantage. “That the technology is rollable and transparent is important,” he said. “But cost is the paramount consideration for a lot of solar applications, which have to be low-cost per watt generated.” The technology is producing cells that are often only two microns thick (a micron is one-millionth of a meter). “Thinner allows cheaper,” he said.

See video in side panel (courtesy sciencecentral.com )

The threat of Black Carbon

2009-07-01T22:03:00.001-07:00

With no cars and little electricity, emissions of carbon dioxide (the main heat-trapping gas linked to global warming) from any small Indian village, are near zero. But soot — also known as black carbon — from millions of villages in developing countries, is emerging as a major and previously unappreciated source of global climate change. While carbon dioxide might be the top contributor to rising global temperatures, scientists say, black carbon has emerged as an important second, with recent studies estimating that it is responsible for 18 percent of the planet's warming, compared with 40 percent for carbon dioxide. In Asia and Africa, stoves produce the bulk of black carbon, although it also emanates from diesel engines and coal plants there. The environmental and geopolitical implications of soot emissions are enormous. Many studies point out that at the current rate of emissions, Himalayan glaciers are expected to lose 75 percent of their ice by 2020,which could dry up rivers resulting in not only human suffering but potential new Geo-political conflicts.

Turn a Blind Eye !

2009-07-01T21:56:00.000-07:00

If global warming is the biggest problem humans have ever caused and the sole civilization-challenging trial the modern world has ever faced,what do most of us do- just watch the slow-motion horror unfold . So far, the planet’s temperature has gone up little more than one degree Fahrenheit,1 but Earth is more finely balanced than we’d realized, and that one degree has been enough to knock it off-kilter. Hydrological cycles have been destabilized—we see massive increases in both droughts and flooding because warm air holds more water vapor than cold. We see increasingly intense storms. And in the last two years we’ve seen a jaw-dropping sight: the runaway melt of Arctic sea ice. This is a sign that the warming human beings kick-started has begun to take on a life of its own; the open Northwest Passage not only proves that the planet is heating up but, because blue water absorbs sunlight that the white ice once reflected, amps up the warming One degree so far, but the consensus suggests that, without truly dramatic action very soon, Earth’s temperature will rise by something on the order of an additional five degrees within this century. And if anything like that happens? Picture this: monsoons shifted off their historic paths. Sea levels rising so high and so fast that you can pretty much forget the coastlines where civilization developed. In fact, we may well end up losing much of civilization. That strikes you as overblown, right? Yet the US National Aeronautics and Space Administration’s James Hansen, our foremost climatologist, wrote in 2008 that “if humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that carbon dioxide will need to be reduced” 2 to no more than 350 parts per million. The key word in that sentence is the last one: reduced. Almost all climate policy work has focused on the idea that we’ll eventually need to cap the amount of carbon in the atmosphere, at 550 parts per million, say, or 450 parts per million. But the melt of the Arctic should kill those cozy plans. We’re at 385 parts per million of carbon dioxide right now, up from 275 before the industrial revolution. Any number above 350 parts per million will push us past all the tipping points. The world comes together in Copenhagen, in December 2009, to strike a new climate deal, a successor to the Kyoto treaty. We have just one last chance to get it right.

Summer Ice in Retreat

2009-07-01T21:46:00.000-07:00

Climatologists at the NASA Goddard Institute for Space Studies (GISS) in New York City have found that 2007 tied with 1998 for Earth’s second warmest year in a century.

The temperature data used came from weather stations on land, satellite measurements of sea ice temperature since 1982 and data from ships for earlier years. The eight warmest years in the GISS record have all occurred since 1998, and the 14 warmest years in the record have
all occurred since 1990.

Over the past 30 years the Earth has warmed by about 0.6°C or 1.08°F. The greatest warming in 2007 occurred in the Arctic, and neighboring high latitude regions. Global warming has a larger affect in polar areas, as the loss of snow and ice leads to more open water, which absorbs more sunlight and warmth. Snow and ice reflect sunlight; when they disappear, so too does their ability to deflect warming rays. The large Arctic warm anomaly of 2007 is consistent with observations of record low geographic extent of Arctic sea ice in September 2007.The concentration of CO2 in atmosphere has risen by 70% since 1970. More Greenhouse gases means higher temperature which causes ice cover to melt and thereby increasing heat absorption which further increases temperature...the cycle goes on.

1891 to 2006: The animation to the right shows a basic demonstration of the increase in annual mean temperature in ten year increments from 1891 through 2006. Warmest temperatures are shown in red