Posts tagged Boulder
CU: Gas-fired plants help clean the air
Jan 10th
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.
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.
-CU-
Ma Nature’s sky light show on the way
Jan 9th
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, 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/.
-CU-
More assistance for flood victims
Jan 6th
Long-Term Flood Recovery Group of Boulder County is Now Accepting Requests for Assistance
Group is taking information about flood-affected residents with unmet needs
Boulder County, Colo. – The Long-Term Flood Recovery Group (LTFRG) has opened a phone line and website for anyone in Boulder or Broomfield counties seeking assistance related to unmet needs from September’s flood. Residents needing help are encouraged to fill out the very short contact form on the website or call the hotline number to leave a brief message. Volunteer members of the group will be returning residents’ messages to do an initial intake interview which will place residents in group’s system. Case managers will be assigned over the next several weeks to residents in need and act as a guide to available resources in the county and work with residents to develop a recovery plan. The LTFRG is volunteer-based and is in a start-up phase, so patience is requested of the community while the process is developed and streamlined.
The LTFRG is charged with managing and distributing the Foothills Flood Relief Fund and also is working to secure additional donations. Donations can be made to the Fund which is housed at Foothills United Way, atwww.unitedwayfoothills.org.
The Long-Term Flood Recovery Group (LTFRG) has launched a website, at www.BoCoFloodRecovery.org, a phone number (303-895-3429) and email address (floodrecovery@unitedwayfoothills.org) for flood survivors to access and request assistance.
As the rebuilding and recovery phase proceeds, people in our community will need many resources, not all of which will be financial. The LTFRG will identify continuing needs for assistance and the process for allocating resources to ensure the long-term recovery of our whole community. Non-financial resources may include donations of critical products, volunteer construction crews, housing re-construction and repair assistance and supporting community visioning and planning processes. Ultimately, the goal is to support as many people who were affected by the September floods as possible.
The LTFRG is actively seeking volunteers for case managers and hotline responders. To sign up to volunteer, please visit http://volunteer.unitedwayfoothills.org/.
























