CU News
News from the University of Colorado in Boulder.
CU: Gas-fired plants help clean the air
Jan 10th
U.S. power plant emissions down with natural gas/new technology
Power plants that use natural gas and a new technology to squeeze more energy from the fuel release far less of the greenhouse gas carbon dioxide than coal-fired power plants do, according to a new analysis accepted for publication Jan. 8 in Earth’s Future, a journal of the American Geophysical Union. The so-called “combined cycle” natural gas power plants also release significantly less nitrogen oxides and sulfur dioxide, which can worsen air quality.
“Since more and more of our electricity is coming from these cleaner power plants, emissions from the power sector are lower by 20, 30 even 40 percent for some gases since 1997,” said lead author Joost de Gouw, an atmospheric scientist with NOAA’s Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder. NOAA is the National Oceanic and Atmospheric Administration.
The decommissioned Arapahoe power plant in south Denver.
De Gouw, who works at NOAA’s Earth System Research Laboratory (ESRL), and his NOAA and CIRES colleagues analyzed data from systems that continuously monitor emissions at power plant stacks around the country. Previous aircraft-based studies have shown these stack measurements are accurate for carbon dioxide (CO2) and for nitrogen oxides and sulfur dioxide. Nitrogen oxides and sulfur dioxide can react in the atmosphere to form tiny particles and ozone, which can cause respiratory disease.
To compare pollutant emissions from different types of power plants, the scientists calculated emissions per unit of energy produced, for all data available between 1997 and 2012. During that period of time, on average:
- Coal-based power plants emitted 915 grams (32 ounces) of CO2 per kilowatt hour of energy produced;
- Natural gas power plants emitted 549 grams (19 ounces) CO2 per kilowatt hour; and
- Combined cycle natural gas plants emitted 436 grams (15 ounces) CO2 per kilowatt hour.
In combined cycle natural gas plants, operators use two heat engines in tandem to convert a higher fraction of heat into electrical energy. For context, U.S. households consumed 11,280 kilowatt hours of energy, on average, in 2011, according to the U.S. Energy Information Agency. This amounts to 11.4 metric tons per year of CO2 per household, if all of that electricity were generated by a coal power plant, or 5.4 metric tons if it all came from a natural gas power plant with combined cycle technology.
The researchers reported that between 1997 and 2012, the fraction of electric energy in the United States produced from coal gradually decreased from 83 percent to 59, and the fraction of energy from combined cycle natural gas plants rose from none to 34 percent.
That shift in the energy industry meant that power plants, overall, sent 23 percent less CO2 into the atmosphere last year than they would have, had coal been providing about the same fraction of electric power as in 1997, de Gouw said. The switch led to even greater reductions in the power sector’s emissions of nitrogen oxides and sulfur dioxide, which dropped by 40 percent and 44 percent, respectively.
The new findings are consistent with recent reports from the Energy Information Agency that substituting natural gas for coal in power generation helped lower power-related carbon dioxide emissions in 2012.
The authors noted that the new analysis is limited to pollutants emitted during energy production and measured at stacks. The paper did not address levels of greenhouse gases and other pollutants that leak into the atmosphere during fuel extraction, for example. To investigate the total atmospheric consequences of shifting energy use, scientists need to continue collecting data from all aspects of energy exploration, production and use, the authors concluded.
Authors of the new paper, “Reduced Emissions of CO2, NOx and SO2 from U.S. Power Plants Due to the Switch from Coal to Natural Gas with Combined Cycle Technology,” are de Gouw (CIRES), David Parrish (NOAA ESRL), Greg Frost (CIRES) and Michael Trainer (NOAA).
CIRES is a joint institute of NOAA and CU-Boulder.
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Ma Nature’s sky light show on the way
Jan 9th
Jan. 9, 2014
University of Colorado Boulder space weather experts say a powerful solar storm may cause the aurora borealis to light up as far south as Colorado and New Mexico in the coming nights.
http://youtu.be/Ip2ZGND1I9Q
Aurora borealis may dip into state
tonight, say CU-Boulder experts
Daniel Baker, director of CU-Boulder’s Laboratory for Atmospheric and Space Physics, said space weather forecasts indicate there is a good chance a coronal mass ejection tied to a large solar flare from the sun Tuesday may impact Earth today, hitting the planet’s outer magnetic shield and causing spectacular light displays tonight and perhaps tomorrow night. National Oceanic and Atmospheric Administration experts have estimated there is a 90 percent chance a coronal mass ejection will hit Earth today.
The aurora borealis could reach as far as New Mexico, last 4-5 nihjts
“The aurora borealis, or ‘false dawn of the north,’ are brilliant dancing lights in the night sky caused by intense interactions of energetic electrons with the thin gases in Earth’s upper atmosphere,” said Baker. “The aurora are most commonly seen in Alaska, northern Canada and Scandinavia when the sun sends out powerful bursts of energy that can strike Earth’s protective outer magnetic shield called the magnetosphere,” he said.
“The strong solar winds associated with the storm events generate strong electric currents when they blow by the Earth’s magnetosphere,” said LASP Research Associate Bill Peterson. “These currents become unstable and drive processes in the magnetosphere that accelerate electrons down magnetic field lines where they hit the atmosphere over the poles.”
“One can think of aurora in some ways as if the Earth’s atmosphere is a giant TV screen and the magnetosphere generates intense beams of electrons that blast down along magnetic field lines to produce the red and green light picture show,” said Baker. “If the sun produces extremely powerful energy outbursts, the aurora can move to much lower latitudes than normal and then one can see the fantastic light displays in the lower 48 states, even as low in latitude as Colorado and New Mexico.”
According to Peterson, geophysicists have been measuring magnetic activity – essentially “wiggles” on instruments measuring Earth’s magnetic field – for over a century. The scientists have come up with a planetary magnetic index known as KP, ranging from 0 (quiet) to 9 (very active).
“The aurora is typically seen in Canada for KP less than 4,” Peterson said. “When the KP is 9, auroras can sometimes be seen as far south as Mexico City. Auroras are seen in Colorado when the KP is about 7.”
Peterson suggested those interested in seeing the northern lights or want to report sightings visithttp://www.aurorasaurus.org, a website called “Aurorasaurus” and led by the Los Alamos National Laboratory in New Mexico. The site is designed as a real-time map of confirmed aurora sightings and includes a place for citizen-scientists who want to participate to report aurora sightings in their own neighborhoods.
For additional information visit NOAA’s Space Weather Prediction Center at http://www.swpc.noaa.gov. For more information on LASP visit http://lasp.colorado.edu/home/.
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Space flight to test antibiotic’s effectiveness
Jan 3rd
CU-Boulder to fly antibiotic experiment,
education project on ants to space station
education project on ants to space station
NASA Television will provide live coverage of the launch of Orbital Sciences Corp.’s commercial Cygnus spacecraft on Tuesday, Jan. 7 from NASA’s Wallops Flight Facility in Virginia, which will be carrying two University of Colorado Boulder payloads to the International Space Station.
The two CU-Boulder payloads — a biomedical antibiotic experiment and an educational K-12 experiment involving ant behavior in microgravity — are slated to be launched aboard Orbital Sciences Corp.’s Antares rocket at 11:55 a.m. MST. Both experiments were designed by BioServe Space Technologies, a NASA-funded center in CU-Boulder’s aerospace engineering sciences department.
The CU-Boulder biomedical experiment was designed to test the effectiveness of antibiotics in space. Past experiments by CU-Boulder and other institutions have shown bacterial susceptibility to antibiotics is significantly reduced during spaceflight, although the reason is not yet known, said CU-Boulder Associate Professor David Klaus, principal investigator on the project.
Klaus said the investigation will examine changes in the gene expression of the bacteria E. coli during exposure to different concentrations of antibiotics while in the microgravity environment of space. The hope is to locate particular genes that are key to resisting antibiotics, which could lead to improved testing on Earth as well as new drug targets or new approaches to understanding antibiotic resistance in certain diseases or infections, said Klaus.
“Previous studies carried out in microgravity have shown that bacteria are able to grow in what normally would be an inhibitory concentration of the antibiotic,” said Klaus. “This investigation is aimed at characterizing the genetic basis for this response in the weightless environment of space with the intent of applying any insight gained toward combating the increasing emergence of drug-resistant pathogens here on Earth.”
Co-investigators on the project include BioServe Director Louis Stodieck, a research professor in aerospace engineering, and Shawn Levy, a researcher at the HudsonAlpha Institute for Biotechnology in Huntsville, Ala. The research effort also involves CU-Boulder doctoral candidate Luis Zea.
Bacterial resistance to antibiotics kills 100,000 Americans every year and represents a roughly $20 billion expense to the U.S. government in excess health care costs, said Klaus. The experiments will be undertaken using spaceflight test tubes contained in the Commercial Generic Bioprocessing Apparatus, or CGBA, an automated, suitcase-sized incubator, all designed and built by BioServe.
The second experiment launching to ISS is known as Ants in Space, which examines foraging patterns based on the density of the common Pavement Ant, said BioServe Business Development Manager and Education Program Director Stefanie Countryman. “Past experiments by Professor Deborah Gordon, principal investigator on this project, have shown that some ant species have the ability to search areas collectively without individual communication. When ant densities are high, each ant thoroughly searches one small area in a circular, “random” walk, she said. When ant densities are low, each ant searches by walking in a relatively straight line, allowing it to cover more ground.
“Ants assess their own density at the rate at which they meet,” said Countryman, who said the eight individual ant habitats on ISS will be loaded with roughly 100 ants each. “The experiment examines whether in microgravity ants will use the rate at which they meet to assess density, and so use straighter paths in the larger habitat areas. The results will be compared to ground controls, which in this case will include ant habitats in hundreds of K-12 classrooms around the world.”
Countryman has previously directed BioServe K-12 education experiments involving the behavior of butterflies, ladybugs and spiders in space, reaching hundreds of thousands of students around the world in the past two decades. For the ant experiments, BioServe is partnering with the Baylor College of Medicine’s Center for Education Outreach, a longstanding BioServe partner that has developed the education curriculum guide for the experiment.
BioServe research partners on the ant project include Gordon of Stanford University and Associate Professor Michael Greene of the University of Colorado Denver. The experiment is sponsored by NASA’s National Lab Education Office as well as the Center for the Advancement of Science in Space, a nonprofit group headquartered in Cape Canaveral, Fla.
Teachers interested in participating in the ant experiments may contact Countryman at countrym@colorado.edu. More information on the project for teachers and students will be online beginning in mid-January at http://www.bioedonline.org.
The flight will be the first Cygnus resupply cargo mission launched to ISS by Orbital Sciences Corp. and follows the earlier, successful launch of a Cygnus demo flight to ISS that arrived at the orbiting station Oct. 22.
In the past 25 years, BioServe has designed, built and flown microgravity life science research experiments on more than 40 space missions. BioServe has a full suite of space flight hardware, both on ISS and on the ground, which supports its own research as well as research conducted by its customers and partners. Past BioServe partners include large and small pharmaceutical and biotechnology companies, universities and NASA-funded researchers.
For more information on BioServe visit http://www.colorado.edu/engineering/BioServe/index.html.
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