The U.S. Department of Energy has estimated that if the United States is to generate 20% of its electricity from wind, over 50 GW will be required from shallow offshore turbines. Hurricanes are a potential risk to these turbines. Turbine tower buckling has been observed in typhoons, but no offshore wind turbines have yet been built in the United States. We present a probabilistic model to estimate the number of turbines that would be destroyed by hurricanes in an offshore wind farm. We apply this model to estimate the risk to offshore wind farms in four representative locations in the Atlantic and Gulf Coastal waters of the United States. In the most vulnerable areas now being actively considered by developers, nearly half the turbines in a farm are likely to be destroyed in a 20-y period. Reasonable mitigation measures—increasing the design reference wind load, ensuring that the nacelle can be turned into rapidly changing winds, and building most wind plants in the areas with lower risk—can greatly enhance the probability that offshore wind can help to meet the United States’ electricity needs.

doi: http://dx.doi.org/10.1073/pnas.1111769109

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A controversial method of drilling for natural gas, called fracking, has boomed in recent years—as have concerns over its potential to cause environmental contamination and harm human health. But a major review of the practice, released today, uncovered no signs that it is causing trouble below ground. “We found no direct evidence that fracking itself has contaminated groundwater,” said Charles Groat of the University of Texas (UT), Austin, who led the study.The report, released here at the annual meeting of the American Association for the Advancement of Science (which publishes ScienceNOW), doesn’t give this form of natural gas extraction a clean bill of health. Rather, it suggests that problems aren’t directly caused by fracking, a process in which water, sand, and chemicals are pumped into wells to break up deep layers of shale and release natural gas. Instead, the report concludes, contamination tends to happen closer to the surface when gas and drilling fluid escapes from poorly lined wells or storage ponds.

Mixed Verdict on Fracking – ScienceNOW

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A protracted legal battle over an $11.5-million health study into whether diesel exhaust damages the lungs of miners has suddenly widened to take on scientific peer review. Editors with at least four research publications say they have received a letter advising them against “publication or other distribution” of data and draft documents. The warning, including a vague statement about “consequences” that could ensue if the advice is ignored, is signed by Henry Chajet, an attorney at the Patton Boggs firm in Washington, D.C., and a lobbyist for the Mining Awareness Resource Group, which works on behalf of the mining industry.Chajet declined to comment, but his letter makes it clear that he seeks to persuade journals to delay publishing or distributing papers containing results from the Diesel Exhaust in Miners Study (DEMS), a government-funded research project. His letter pointed out that a coalition of mining industry groups are legally entitled to review data from the study before publication. Other lawyers and researchers involved in the case also declined comment because the 2-decade-long dispute over DEMS is now under review in the U.S. Court of Appeals in New Orleans.

Journals Warned to Keep a Tight Lid on Diesel Exposure Data – ScienceInsider

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In the RAS a gradual increase in CO₂, decrease in pH and dissolved oxygen was observed over time. This was most obvious during experiment two, when the total organic carbon content increased in both FTS and RAS. The total bacterial number was lower and more stable in FTS than in the RAS. The variations in seawater quality parameters were smaller during the first experiment compared to the second, when values of oxygen saturation were reduced to <70%, pH was 7.8 and NO₃⁻ reached 5 mg L⁻¹. Even though these changes would seem less beneficial for survival and growth of scallop larvae, results showed that the survival at the end of the larval stage was higher in the FTS, but the yield of competent larvae ready for settlement was not significant different (p > 0.05) due to large variations between tanks. The CV% was 28.9% in FTS, while it was 49.9% in RAS. In FTS the mean yield was 40.2%, while it was 26.5% of initial number of larvae in RAS. Large variations in survival and yield were found between the larval tanks as well as gradual reduction in pH and oxygen in RAS tanks. The results indicate that there is a large potential for 80% reduction in water use by utilizing recirculation technology.

DOI: http://dx.doi.org/10.1016/j.aquaeng.2011.12.005

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Turns out that researchers at the Department of Energy’s BioEnergy Science Center, located Caldicellulosiruptor obsidiansis, a naturally occurring bacterium, onsite at Yellowstone, Sure enough, it thrives at extremely high temperatures, breaks down organic material such as sticks and leaves in its natural environment, and scientists hope to transfer this capability to biofuel production tanks.

A team out of Lee Lynd’s lab at Dartmouth has been at work on Thermoanaerobacterium saccharolyticum, a thermophilic anaerobic bacterium that ferments xylan and biomass-derived sugars, to produce ethanol at high yield.

University of Texas researchers Alan Lambowitz and Georg Mohr have been working on Thermosynechococcus elongatus, a cyanobacterium discovered in Japan that can survive at temperatures of up to 150 degrees Fahrenheit.

A team of researchers from the DOE, Novozymes and Concordia University have been unlocking the genome of Thielavia terrestris and Myceliophthora thermophila, fungi that thrive in high-temperature environments above 45°C and whose enzymes remain active at temperatures ranging from 104°F to 160°F (40 °C to 75 °C),

We also recently looked at at work by biologists at Berkeley and the University of Maryland, who discovered a microbe in a Nevada hot spring that has an enzyme that processes cellulose and remains active at a record 109 degrees Celsius (228 degrees Fahrenheit), significantly above the 100℃ (212℉) boiling point of water.

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New composite proton exchange membranes prepared through layer-by-layer coating of a biopolymer has shown superior methanol barrier properties, while maintaining a high affinity to proton transfer same time. The highly selective skin layer in the composite system significantly increases the fuel utilization efficiency in direct methanol fuel cells (DMFCs).

DOI: http://dx.doi.org/10.1002/cssc.201100366

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