Solving Our Energy Problems--Slowly
With computer mouse in hand, Jack Halow controls the swirling plumes of blue and yellow on his display screen.
Each click magnifies the colored streams of tiny bubbles that mix and flow together. Another few clicks and Halow’s vantage point is from inside the current.
Instead of analyzing pages of data, this high-tech imaging allows him to see how tiny pellets of zinc oxide, represented by one bubble plume, can be positioned to capture air pollutants produced when coal is burned. The pollutants are depicted by the other bubble stream.
“It’s like a personal Omnimax,” Halow said. “If a picture is worth a thousand words, an animation is worth a million numbers.”
Halow is director of systems and multiphase flow analysis at the National Energy Technology Laboratory in Morgantown. The lab has one mission--performing basic science involving coal, natural gas and other fuels that could someday help solve world energy problems.
The key word is someday: Most of the 1,100 research projects here and at satellite facilities in Pittsburgh and Tulsa, Okla., are done with a long-range view.
“We’re not going to have an impact on the California crisis tomorrow,” said Rita Bajura, the lab’s director. “The cycle time in energy is a little different than the cycle time with Barbie dolls.”
Yet even if it takes the lab another decade to solve problems presented by greenhouse gases or an aging pipeline network that may not meet demand for natural gas, Bajura says that timeline would outpace the private sector, where the overriding concern is profit.
“We’re doing research for the public, so we’re only successful if it goes to the private sector,” Bajura said.
But the lab’s intention is not just to enrich industry. There must be a public policy benefit--in this case, cleaner air.
That’s why Halow and others are focusing on the zinc oxide pellets.
Coal is cheap and plentiful, but burning it produces the pollutant sulfur dioxide, so researchers are developing other combustion techniques, including gasification--partially burning the coal to create gas that powers a turbine to generate electricity. Gasification, however, creates hydrogen sulfide, a different air pollutant.
Senior scientist Ranjani Siriwardane has refined the zinc oxide pellets to absorb hydrogen sulfide in a slender glass tube under lab conditions.
In the next level of experimentation, researcher Larry Lawson and his team use ground cork to simulate how the pellets would behave under real conditions. The cork’s motion is monitored on computers and in clear pipes.
“Insurance companies don’t want to insure the technology until they’re sure you can do it safely,” Lawson said. “You’ve got to cover all the bases.”
Even after the lab testing, the question remains--would the process work in a real power plant?
The lab has its own 3-megawatt plant where in the coming months researchers will encase a ton of zinc oxide in cement-lined pipes and subject them to high heat and pressure. Only if the pellets work at this stage will the lab consider recommending the technology for use in commercial plants.
The lab began as the Appalachia Experiment Station in 1954, and for more than 20 years did only in-house research on natural resources. It expanded through the 1970s and 1980s, moving into the Department of Energy and taking on the clean coal technology program before becoming a national lab in 1999.
Larry Headley, director of the lab’s Office of Science and Technology, says most coal-fired power plants tap only 30% of the coal’s potential energy. Gasification brings the level to 50%, but Headley envisions a fuel-flexible plant that will someday run on natural gas, coal and other sources of energy at 80% efficiency.
“If your efficiency is two or three times greater, you can build a plant that’s two or three times smaller and get less environmental impact,” he said.
Bajura says there is no silver bullet when it comes to energy.
“If anyone says this one thing is the only thing that will solve it, it’s not true,” she said. “We need all of our energy sources, and we need more conservation. But it’s up to society to come out to this optimum balance. It’s up to society to say how we do the most public good for the most people for the longest time.”
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On the Net:
National Energy Technology Laboratory: https://www.netl.doe.gov/
