Environmental News
Environmental News from Boulder, Colorado
CU scientists discover earlier warming period
Oct 7th
Oct. 7, 2010
If you think global warming is bad, 11 billion years ago the entire universe underwent what might be called universal warming. The consequence of that early heating was that fierce blasts of radiation from voracious black holes stunted the growth of some small galaxies for a stretch of 500 million years.
That is the conclusion of a team of astronomers led by the University of Colorado at Boulder who used the new capabilities of NASA’s Hubble Space Telescope to probe the invisible, remote universe.
Using the newly installed Cosmic Origins Spectrograph, or COS, the team identified an era from 11.7 to 11.3 billion years ago when the universe stripped electrons off from primeval helium atoms — a process called ionization. This process heated intergalactic gas and inhibited it from gravitationally collapsing to form new generations of stars in some small galaxies. The lowest-mass galaxies were not even able to hold onto their gas, and it escaped back into intergalactic space.
CU-Boulder Professor Michael Shull of the astrophysical and planetary sciences department and his team were able to find the telltale helium spectral absorption lines in the ultraviolet light from a quasar — the brilliant core of an active galaxy. The quasar beacon shines light through intervening clouds of otherwise invisible gas, like a headlight shining through a fog. The beam allows for a core-sample probe of the clouds of gas interspersed between galaxies in the early universe.
The universe went through an initial heat wave over 13 billion years ago when energy from early massive stars ionized cold interstellar hydrogen from the Big Bang. This time period is called the Reionization Epoch because the hydrogen nuclei were originally in an ionized state shortly after the Big Bang, said Shull, also a faculty member at CU-Boulder’s Center for Astrophysics and Space Astronomy, or CASA.
A paper on the subject will be published in the Oct. 20 issue of The Astrophysical Journal. Co-authors included CASA Research Associate Kevin France, CASA Research Associate Charles Danforth, CASA postdoctoral researcher Britton Smith and Jason Tumlinson of the Space Telescope Science Institute in Baltimore.
But the Hubble data indicated it would take another 2 billion years before the universe produced sources of ultraviolet radiation with enough energy to do the heavy lifting and reionize the primeval helium that also was cooked up in the Big Bang.
This radiation didn’t come from stars, but rather from quasars, said Shull. In fact, the epoch when the helium was being reionized corresponds to a transitory time in the universe’s history when quasars were most abundant.
The universe was a rambunctious place back then, Shull said. Galaxies frequently collided and this engorged supermassive black holes in the cores of galaxies with gas falling in. The black holes furiously converted some of the gravitational energy of this mass to powerful far-ultraviolet radiation that would blaze out of galaxies. This heated the intergalactic helium from 18,000 degrees Fahrenheit to nearly 40,000 degrees.
After the helium was reionized in the universe, intergalactic gas again cooled down and dwarf galaxies could resume normal assembly. “I imagine quite a few more dwarf galaxies may have formed if helium reionization had not taken place,” said Shull.
So far Shull and his team only have one sightline from Hubble to measure the helium transition, but the COS science team plans to use Hubble to look in other directions to see if the helium reionization uniformly took place across the universe.
The $70 million COS instrument, inserted during the final Hubble servicing mission in May 2009 was designed by a team from CU-Boulder led by Professor James Green and was built primarily by Ball Aerospace & Technology Corp. of Boulder.
SOURCE: CU-BOULDER MEDIA RELEASE
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Boulder Supporters for Clean Energy
Aug 4th
by Donna Marek, Cultural Affairs Reporter
UPDATE: August 4 11:00 am
It Had to Happen
The City of Boulder will not renew the Xcel Energy Franchise Agreement according to a 6-2 vote at the Council meeting last night. City Manager Jane Brautigam’s stand was like a song ” let the contract go.”
Voters will be asked to vote in November for a special tax which, of course, would be passed on to consumers using Xcel energy. Looks like yellow shirt
Boulder Yellow Shirts Took the Street Corners Tonight!
All you have to do is put a piece of coal in your stocking…twirl around three times…and make a wish that Xcel Energy will go away and the City of Boulder will take over the community energy problems! Oh, my goodness! What did I say?
Well, on Tuesday, August 3 at about 5:30pm in front of Boulder’s Municipal Building, a crowd of supporters for the City’s taking on the energy issue, buying Xcel energy and making it environmentally politically correct took place with about 200 people on the corners of Broadway and Canyon.
I talked to two gentlemen who support the City’s stance. Tyler said, “I support the city for not renewing the Xcel franchise.” He said he was supporting renewable energy as an option. While Ken said he saw Boulder aggressively decreasing the carbonizing “but not as much as we’d like for Xcel. This is a “groundswell” with two paths,” he said. One is with Xcel committing to clean energy and the second looks at monopolizing energy! Anyway, there were children, parents, grandparents and they even held a press conference.
When I asked these two supporters about the City’s already stretched budget, Ken said “The City can afford it because citizens are already paying for it!”
So…
Boulder Supporters of City’s Stand on Xcel Energy and clean energy
It was a lovely, peaceful gathering with horns tooting and people waving signs. The weather was phenomenal!
I dare not say more!
Boulder City Council to discuss Xcel franchise Tuesday
Jul 30th
Boulder City Council to discuss franchise Tuesday
Staff recommends utility occupation tax instead of new franchise
Staff recommends utility occupation tax instead of new franchise
The City of Boulder may ask voters to support a limited-term utility occupation tax instead of a franchise agreement with Xcel Energy.
Boulder City Manager Jane Brautigam will ask City Council on Tuesday, Aug. 3, to give the city more time to chart out its energy future, recommending that council decline to place a 20-year Xcel franchise agreement on the ballot this November. The staff recommendation follows months of analysis and negotiations with Xcel Energy.
The current franchise agreement was set to expire Aug. 3, and has been extended by Xcel through Dec. 31, 2010. The agreement gives the utility access to the city’s streets, alleys and other rights-of-way for the purpose of providing gas and electricity to Boulder consumers. In exchange for the rights-of-way, Xcel pays $3.9 million to the city.
Whether the city enters into a new franchise or not, Xcel Energy is required to continue to provide gas and electricity to Boulder customers. The city manager’s recommendation to go out of franchise will have no impact on the energy services provided by Xcel. However, the decision may result in a loss of $3.9 million to the city’s General Fund.
Without a franchise agreement, the utility will no longer be required to collect a 3 percent franchise fee from its customers. The money is used to help pay for core services, including police, fire, libraries, parks, human services and public works.
Brautigam said the franchise revenue could be replaced with a utility occupation tax on Xcel if council supports this option and voters approve it in November.
Brautigam is recommending that council place a five-year occupation tax on Xcel on the ballot for voter consideration on Nov. 2. The revenue measure is not a new tax on voters. The tax is on Xcel and replaces the franchise fee. The utility will likely pass the cost onto ratepayers as it does with the current franchise fee.
The measure maintains the integrity of the city’s budget and provides important funding for core services. The proposed tax expires in five years, providing the needed time to
study the best ways to meet Boulder’s renewable energy goals. In addition to replacing
the $3.9 million franchise fee, council will be asked to consider including $450,000 per year in the revenue measure to fund a decarbonization study that explores the city’s long-term energy options.
“Our voters have told us very clearly that they support alternative sources of energy and want Boulder to be a leader in moving toward a cleaner supply,” said Brautigam. “While we appreciate Xcel’s efforts and commend them for working with us during this process, the city is not prepared to enter into a 20-year agreement at this time. I am asking council to keep all of our options open and give city staff and outside experts time to examine where the industry is going and how we best can achieve the community’s goals.”
Brautigam emphasized that the recommendation does not rule out the possibility of a franchise agreement with Xcel Energy at some later date. That option, along with others, including municipalization, should remain under consideration.
“We value Xcel’s services and the partnerships we have formed with their employees,” Brautigam said.
Council will consider these recommendations at its regularly scheduled meeting at 6 p.m. on Tuesday, Aug. 3, in City Council Chambers, 1777 Broadway. A detailed memo to council will be available by the end of today at www.bouldercolorado.gov/energyfuture.
