The first Chevrolet Volt cars to roll off production lines at a General Motors Co. plant in Michigan are going 40 miles on a single battery charge as promised, the plug-in hybrid electric vehicle’s head engineer said yesterday.
“I’m very confident that the batteries are delivering the energy that they need to deliver and that the vehicle’s efficiencies are where it should be,” chief engineer Andrew Farah told the Detroit Free Press. “We’re still doing a few last-minute tweaks and tunes on the aerodynamics but, again, that’s just to stabilize some things.”
Pre-production of the Volt began about two weeks ago. The car is scheduled for launch in November.
Unlike the all-electric Nissan Leaf, also slated for launch late this year, the Volt is equipped with a gasoline engine to keep the car running once it uses up its electric charge. Total electric range varies depending on terrain and weather, but the car is meeting expectations, Farah said.
“This weekend alone, I had at least two cycles that were over 40 miles,” Farah said. “I think I drove one at 41.5 and another 42.5″ miles.
A new approach to fabricating light-emitting diodes (LEDs) could be used to increase their efficiency by 20 percent while yielding higher-quality light than conventional LEDs. Researchers at the National Renewable Energy Laboratory (NREL) in Golden, CO, have demonstrated the approach by making a yellow-green LED that could soon be combined with other colored LEDs to yield white light. The new LED could help replace current, inefficient methods of generating white light.
LEDs, devices that emit photons when an electrical charge is applied to them, are more efficient and last longer than incandescent lightbulbs. By varying the composition of the semiconductor LEDs, materials scientists can coax the devices into emitting different colors. At the minimum, producing white light requires combining red, blue, and green, but so far, only red- and blue-light-emitting diodes are well developed. To produce green light, LED manufacturers typically apply one or more phosphor materials to blue LEDs. The phospors convert high energy blue spectrum light into lower-energy light through a process that reduces overall luminosity by approximately 20 percent.
To eliminate this loss of efficiency, researchers have tried to develop efficient green LEDs that don’t require phosphors. But a major stumbling block is that the different known semiconductor materials that can be combined to emit green light, typically indium and gallium nitride, have different-sized crystal lattice structures. For semiconductors to work efficiently, each layer of the device has to have a similarly sized lattice structure as the layer above or below it.
To get around the lattice-size mismatch, NREL researchers used a fabrication method that they had previously developed for building highly efficient multi-junction solar cells. Their method relies on using additional layers of other semiconducting materials with intermediate-sized lattice structures that bridge the gap between the disparate-sized semiconductors. “If you try to do it in one shot, the whole thing will be defective,” says Angelo Mascarenhas, team leader for solid state spectroscopy in the Center for Basic Sciences at NREL. “You have to grow a sequence of layers in a step-wise fashion.”
The coal industry includes companies that profess to support climate legislation but are in fact operating behind the scenes in “stealth mode” to deny climate science and thwart needed action on climate change.
Consider two of the coal companies that keep their heads down and yet still do a lot of damage: Peabody Energy Company, the world’s largest private-sector coal producer, and Arch Coal, the second largest U.S. coal producer.
Peabody claims to support climate legislation, but it has been identified as a key figure in opposition to climate legislation.
Climate change could push the cost of U.S. allergies and asthma beyond the current $32 billion annual price tag, conservation and health groups reported on Wednesday.
A warming planet makes for longer growing seasons that would produce more allergy-provoking pollen in much of the heavily populated eastern two-thirds of the United States, the National Wildlife Federation and the Asthma and Allergy Foundation of America said in their report.
The cost of coping with allergies and allergen-driven asthma in the United States is at $32 billion in direct medical costs, lost work days and lower productivity, the report said.
“Climate change could allow highly allergenic trees like oaks and hickories to start replacing pines, spruces and firs that generally don’t cause allergies, exposing many more people to springtime allergy triggers,” said Amanda Staudt, a climate scientist at the wildlife federation.
President Obama today urged Americans to honor the upcoming 40th anniversary of Earth Day by acting to improve the environment around them and launched a Web site, Whitehouse.gov/EarthDay, compiling citizens’ success stories.
In the video message above, Mr. Obama describes how the first Earth Day was prompted in part by vivid incidents like a fire on the pollution-stained Cuyahoga River in Cleveland. He listed that era’s suite of environmental laws, most of which were enacted under a Republican president in a time of environmental bipartisanship that long ago vanished from Capitol Hill.
Clearly with today’s Washington paralysis in mind, Mr. Obama notes that people shouldn’t count on elected officials to solve all environmental problems and “should take steps in their own homes and their own communities.” That’s always a fine message. Little acts are valuable, even in the face of planet-scale problems.
That the American South is both a voracious consumer of energy and a laggard on implementing efficiency measures has long been a matter of some concern for policymakers and energy analysts.
A 2007 report by Forbes magazine, for example, ranked states according to a composite score in six categories: carbon footprint, air quality, water quality, hazardous waste management, policy initiatives and energy consumption.
Top honors went to states like Vermont, Oregon, Washington, Hawaii, Maryland, Connecticut and New Jersey. The first Southern state east of Texas listed was Florida “” at number 20. And as noted at the time by Robert Hawley “” then a renewable energy researcher at the Oak Ridge National Laboratory “” Tennessee, Arkansas, Kentucky, Mississippi, Louisiana, Alabama and West Virginia made up seven of the bottom eight on the list. (The were joined by Indiana.)
None of that would be a surprise to the authors of a study released Monday by researchers at the Georgia Institute of Technology and Duke University. Among the chief conclusions: introducing aggressive efficiency measures to industrial processes as well as to the residential and commercial building sectors (transportation was not considered) could well offset the expected growth in energy demand in the South over the next 20 years.