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- I performed the small but wiry role of Sheriff Deon Gilbeau in Reston Community Players’ production of August: Osage County.
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Category Archives: Energy Sources and Consumption
Not so green
Willie D. Jones reports on research (preliminary, apparently not yet published) by the Virginia Water Resources Research Center that compares various energy sources and means of power generation in their efficiency of water consumption. That certain high-tech darlings of alternative energy, like ethanol, are relative water hogs is less surprising than the wide spread of computed values, spanning four orders of magnitude. While natural gas requires only 38 liters of water per 1000 kilowatt-hours generated, biodiesel was measured at 180.9 to 969 kiloliters of water per 1000 kW-h. On the generation side, the range is from 260 l/kW-h for hydroelectricity to 31000 to 74900 l/kW-h.
The Green 500
Wu-Chun Feng and Kirk W. Cameron of Virginia Tech have initiated a new system of league tables for supercomputers based on energy efficiency, The Green500 List. They introduce the rankings in an article in the December, 2007 issue of Computer. The article abstract:
The performance-at-any-cost design mentality ignores supercomputers’ excessive power consumption and need for heat dissipation and will ultimately limit their performance. Without fundamental change in the design of supercomputing systems, the performance advances common over the past two decades won’t continue.
As the methodology is still new, and requires some apples-to-oranges comparisons, it’s not surprising that the listings are dominated by one vendor’s architecture. IBM’s Blue Gene takes the top 26 spots in the table, with energy consumption of 204 to 357 megaFLOPS per watt. Slot #500 comes in 2 orders of magnitude lower, at 3.65 megaFLOPS per watt.
It might work
J Luc Pitard hops in the backseat of one of GM’s hydrogen fuel cell demonstrator vehicles. Robert Seigel takes the wheel of the specially-fitted Chevy Equinox.
Form follows function
Phil Patton previews new designs for hybrid and electric cars. Toyota is showing a spiffy 2-door concept car called the X that features a lot of glass.
Still counting
A new report from the National Academies of Sciences, Environmental Impacts of Wind-Energy Projects, is in pre-publication. As summarized in the press release, the study examined onshore projects only, and concluded that wind projects will have a measurable impact on CO2 emissions by 2020 but will not reduce sulfur dioxide or nitrogen oxide levels.
The report seems to haver on the effects on vertebrate populations—birds and bats:
… the committee saw no evidence that fatalities from existing wind facilities are causing measurable changes in bird populations in the United States. A possible exception is deaths among birds of prey, such as eagles and hawks, near Altamont Pass, Calif.—a facility with older, smaller turbines that appear more apt to kill such birds than newer turbines are.
Too little information is available to reliably predict how proposed new wind projects in the mid-Atlantic highlands would affect bird populations…
Gassing up
Revised testing methodology from the Environmental Protection Agency means substantially reduced gas mileage estimates for hybrid vehicles, as John Gartner reports. This reduction is in keeping with anecdotal reports that mileage estimates for hybirds had been inflated. As an example: while the previous estimates for the Toyota Prius were 60 mpg City/51 mpg Highway/55 mpg Combined, the new numbers are 48/45/46. (Remember that hybrids paradoxically get better mileage for EPA City conditions.)
What Gartner’s report doesn’t point out is that estimates for conventionally-powered cars are also being reduced. The old numbers for the 4-cylinder manual transmission Honda Accord were 26/34/29, dropping about 10% to 23/31/26.
Wildlife & Wind Energy Conference
Wind power isn’t quite the unambiguously benign source of electricity that some have made it out to be—for example, the author of the article for Worldchanging. That’s our big takeaway from the Wildlife & Wind Energy Conference, hosted by the Geography Department of Kutztown University and organized by Donald S. Heintzelman. It was perhaps fitting that attendees encountered blustery weather conditions enroute to the venue, located in Berks County, Pennsylvania, in the Appalachian Mountains, not far from the renowned Hawk Mountain Sanctuary.
The first surprising thing that I learned is how large a state-of-the-art wind turbine is. A typical wind turbine is rated at 1.5 MW, stands 70 meters tall, and its three blades span a diameter of approximately 50 meters. Perhaps, then, it’s not surprising that many consider a row of these turbines arranged along a ridgeline to be a blot on the landscape, although I find the monopole towers supporting three thin blades to be one of the more graceful engineered objects that you might encounter: certainly more attractive than a bristling microwave tower or spiderly powerline structure. The language we use to describe a wind generation facility has become politicized: while supporters popularize the term “wind farm,” cons favor “wind plant.” Finally, most troubling is that wind turbines pose a real threat to flying wildlife, primarily birds and bats. And hence the conference.
Unfortunately, the sessions appeared to be designed more to muster opposition to new wind projects in Pennsylvania and elsewhere in the Appalachians than to entertain a wide spectrum of viewpoints. Two speakers from government were briefly heard, plus a last-minute replacement, out of more than two dozen speakers on the printed agenda, and no industry or trade association officials spoke. Q&A time was given short shrift. We heard from citizen scientists but no engineers.
And it’s too bad, because almost everyone agrees that not only is mortality from collisions with the turbines a serious problem, but also that there’s very little good science that’s been done to understand exactly how serious it is, and why. What’s worse, operators of controversial facilities like Mountaineer Wind Energy Center in West Virginia, after suffering bad publicity from reports of bat kills, have restricted access by researchers to their sites. We didn’t learn at this conference how wind turbine mortality differs from kills at stationary communications towers. We know something, but not a lot, about the different effects on migrating and foraging wildlife, on raptors, songbirds, and bats. We have some anecdotal evidence about the effects of weather: fog and low ceilings can exacerbate. Likewise, it was suggested that quiet-running, preferred by human neighbors, may pose more of a wildlife hazard. What research has been done into mortality is disputed: how do we know that field searchers have found all the carcasses before scavengers have?
More than one speaker struck a defiant NIMBY attitude, among them Laura Jackson of a Bedford County grassroots organization. Speakers cast longing looks at the development potential for Chesapeake Bay and offshore wind farms, but no one spoke about the possible effects on marine mammals, birds, and amphibians.
The most pragmatic notes were sounded by David Riposo, master’s candidate at the University of Maryland’s Marine, Estuarine, and Environmental Science Department, who cited Pacala and Socolow’s “stabilization wedges” concept, which concludes that wind power is but one of many measures that need to be taken to address looming climate change problems; and by Michael Fry of the American Bird Conservancy. The ABC hosted a two-day workshop in 2004, and has taken a qualified positive policy stance on wind power, and Fry’s remarks focused on mitigation and incremental improvements.
Also noteworthy was a last-minute speaker from the Government Accountability Office, who provided hard copies of a September, 2005 report that I haven’t finished digesting. She noted that a National Academy of Sciences report was due for publication in January, 2007. One of the points made by the GAO report, and amplified by other speakers, is that the federal government has a limited role in regulating wind power development. In many states, the burden of oversight falls to counties and municipalities.
Posted in Birds and Birding, Energy Sources and Consumption, Engineering
Tagged read_me
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