N.M. labs take on world's environmental woes
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Sandia, LANL work to understand climate change, meet future energy needs
4/24/2008 - 4/25/08
If the federal government were to make a green-focused Christmas list for New Mexico's national laboratories, it might look something like this:Dear Labs,
Can you ...
1. Create a detailed model of all aspects of the climate so we better understand processes like global warming.
2. Figure out how to reduce emissions from coal-fired power plants and make them a source of clean energy.
3. Recycle some of the carbon dioxide in the air back into fuel, and find a safe way to remove even more of it and store it somewhere so it slows the process of global warming.
4. Make the way energy is transported around the country more efficient and improve alternative energy technologies so we can get more out of them.
5. Find a way to store energy from alternative sources so they can be used as a steady resource.
Oh, and could you hurry up already? The world's in sort of a crisis mode.
The response from Los Alamos and Sandia national labs?
We're on it.
Of course, most of the projects on that wish list won't be finished anywhere near Christmas. But even if they come late, the results will be critical to make the world a safer, cleaner place in the future, said Duncan McBranch, LANL's deputy principal associate director for science, technology and engineering.
"There's been a change in public awareness that the growth of energy demand worldwide is leading to a lot of social, economic and environmental issues," McBranch said. "These are very tough problems to solve. They involve technical challenges, political challenges, and really a lot of fundamental science problems."
And the first step to fixing any of the world's dramatic environmental woes is to figure out exactly what's going on — which is something Los Alamos has been modeling on its supercomputers for some years now, McBranch said.
"Most people don't know that we have a fundamental role in the global climate modeling effort," McBranch said.
The lab is charged with creating and improving two models in a four-model system of climate being developed by labs across the national Department of Energy complex.
The four connected models are: how plants, land and water interact; how the atmosphere works; how oceans circulate; and how sea ice flows and influences other climate aspects. Los Alamos is working on the last two, McBranch said.
"We're working on those because of our supercomputers and our particular expertise in fluid dynamics," McBranch said. "The models are very detailed. You can watch the way ocean circulation drives the formation of the major currents along the Pacific and up from the Gulf of Mexico through Europe."
Still, the hardest part of that modeling is yet to come. The key thing now is to use the models to understand smaller, regional weather patterns and use that understanding to respond to emergencies — like droughts in the West — before they get out of hand, he said.
"As you know this year, locally, we thought it was going to be a very dry winter, and it turned into a very wet winter," McBranch said. "The formation of those ocean circulations is a major factor in the water picture in the Southwest. We need to understand that much better than we do now."
Another issue as the world continues to scramble for new energy sources is to figure out a way to make coal a cleaner, more effective resource for the United States.
The reason for that is simple, McBranch said.
"We're sitting on a whole lot of coal in this country, and we're going to continue using it," McBranch said. "The challenge is, can we capture the carbon dioxide from that so we don't continue emitting large amounts of it into the atmosphere."
Because of the chemical reactions, for every ton of coal we burn, we get three tons of carbon dioxide, which can give you a hint at how immense the problem is, he said.
That carbon dioxide gas spreads quickly through the air and can last for 1,000 years in the atmosphere, he said.
"To fix that, we have to sequester billions of tons of carbon dioxide a year," McBranch said. "To put that into perspective, the average American family produces 10-30 tons of carbon dioxide a year."
Los Alamos is trying to develop special materials to take carbon dioxide out of a smoke stack before it's released into the atmosphere. The lab is also looking at places to put extra carbon dioxide, like under the ocean, into the ground or mixing it with rock to make a sort of artificial limestone, McBranch said.
And Sandia has another idea — recycle it into fuel so you can get another use out of it, said Margie Tatro, director of fuel and water systems at the labs.
"Our first set of steps indicates we could take waste form a coal plant and make more fuel out of it," Tatro said. "We call that sunshine to petrol, and it's early research, but it looks like we could make gasoline out of that."
Sandia is also working on a more controversial fuel source, nuclear power, she said.
"We're really keen on moving this country to more nuclear power, but spent fuel is a problem, as is finding a place to put them," Tatro said. "From an engineering perspective we're looking at systems that can go from being a power source to an end-point that's more environmentally friendly."
Sandia played a major role in the development of the WIPP site and has been working for many years on the Yucca Mountain waste repository.
A problem most people don't think of when they consider the energy crunch is that a huge amount of power is lost in electrical lines as its moved around the country, McBranch said.
Losses on the U.S. grid account for 10 percent of the total energy in the U.S., which equates to about 80 coal-fired power plants and 300 million tons of carbon dioxide emissions a year, he said.
"The reason for that is transmission lines are made of copper, and they lose energy through heat," McBranch said. "What we've been working on is making new materials that are textured on the nanoscale that could be turned into cables that can carry energy with no loss."
Those cables are being tested right now in power sub-stations and aren't yet ready for transmission lines, but in perhaps 10-15 years they could be ready for widespread use, he said.
"Even now, in power transformer substations, they can save a significant amount of power," McBranch said.
Sandia is also involved in the power transmission line problem, but from an engineering angle, Tatro said.
"We're working on the system integration side," Tatro said. "We're looking at how the electrical grid interfaces with power stations and other areas to see if we can make them more efficient."
And Sandia is also looking at new ways to connect alternative energy sources — like wind farms or solar cells — to the grid, she said.
"One of the problems adding those sources is it's just very expensive," Tatro said. "Also, the electric grid was really not built for sources of electricity coming from several places. It was meant to have power coming from one spot. So when you add new ones, you have to be careful how you integrate them."
Sandia is working on alternative energy sources as well, such as finding the best ways to make integrated solar farms, improving wind turbine design and investigating technologies to access geothermal energy from deep in the ground, she said.
Los Alamos is also working on solar technologies and the creation of improved hydrogen fuel cells that could power cars or larger vehicles.
But there's a bigger problem hiding behind those technologies, and that's how to store the energy that comes from them so they can be used when the sun isn't shining, or the wind isn't blowing, McBranch said.
"Right now only 3 percent of our power comes from renewable sources," McBranch said. "If we want to get that to 30 to 50 percent, you have to have power when you need it, and not just when the wind is blowing. So energy storage is a main gap that's been preventing that."
There has been rapid progress in the amount of power that batteries can store, but that technology is starting to top out.
The way to improve it will be to create new materials, atom by atom, on the nano-scale that can store large amounts of energy in a small compartment, he said.
"If you look at computers, magnetic materials used to limit the size of disk drives," McBranch said. "Then a new material was found that could hold a higher magnetic field on a smaller scale. Because of that, we had the whole explosive growth of memory sticks, iPods and portable disk drives. We need that equivalent now in energy storage."
Getting there, however, could put a huge dent in our reliance on coal and nuclear power, and could also reduce Americas reliance on foreign sources of energy, he said.
"If you're looking at an area where the nation needs to make a big investment to fund technology, that's the biggest one," McBranch said. "And its the best way to move to alternative sources, because if you can't make energy cheaply, the public just won't embrace it."
Contact Sue Vorenberg at 986-3072 or svorenberg@sfnewmexican.com.