This is an archived article that was published on sltrib.com in 2008, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.
Posted: 3:31 PM- Coal gasification, an expensive but cleaner way to convert coal into energy, will likely become more widespread, potentially offering breakthroughs in curbing emissions that exacerbate global warming and weaning the U.S. from foreign energy, predicted a Utah chemical engineering professor at a major scientific conference in Boston today.
As regulatory frameworks evolve to address growing alarm over greenhouse emissions associated with coal combustion, gasification will become increasingly attractive on economic grounds, according to Brigham Young University's Larry Baxter, who spoke at the American Association for the Advancement of Science's annual gathering.
"Global warming issues may create gasification's best chance for success," Baxter said of the technology that uses heat and pressure to separate hydrocarbons and biofuels into their gaseous components -- mainly hydrogen, carbon dioxide, carbon monoxide and water. "Gasifiers produce a nearly pure carbon dioxide stream that may be more easily captured and stored than most other processes."
And gasification makes it easier to keep other pollutants associated with coal burning, such as sulfur and nitrous oxides, from reaching the atmosphere. Currently coal accounts for more than half of the nation's and nearly all of Utah's power generation.
"With the nation's energy needs at a forefront and with the high level of coal resources in this country, Professor Baxter's work on coal gasification is not only of scientific interest but also of great importance to all of us," said Richard Rowley, chair of BYU's Department of Chemical Engineering.
Gasification can also can yield transportation fuels in a reasonably efficient manner. A boom in this technology could open new doors for resource extraction in Utah, which holds large reserves of high-quality coal, estimated at 15 billion tons, or enough to feed the nation's needs for 15 years at current levels of consumption.
In generating power, the process uses the waste heat from gasifying coal to drive a turbine. This technology has the potential to produce electricity with much higher thermodynamic efficiency than traditional steam turbines, but those gains are lost when the technology is used to clean up emissions. Given coal's abundance and the preponderance of infrastructure to produce and burn it, this and other fossil fuels will remain a chief component for power generation, experts say.
"Our challenge is to continue to do that and at the same time reduce the impact of carbon emissions," said Dianne Nielson, Gov. Jon Huntsman Jr.'s the Utah governor's energy adviser. "Whatever we do to develop Utah's coal resource, it has to be the best technology in terms of air quality and carbon emissions. We incur huge costs across the economy if we do anything other than use the cleanest technologies."
Gasification technology has been available since World War II when Nazi Germany developed it to produce diesel when it was the target of a fuel embargo. Also out of necessity, China, one of the most coal-rich and energy-hungry nations, currently puts gasification to widespread use.
But "gasification has never really found its footing in the U.S. because of problems of implementation and costs," Baxter said. The complex process costs more to build and to maintain than oil refinement for motor fuel or coal-fired plants for electricity. Gasification still faces many technical hurdles, but they can be solved "through engineering. We don't need a miracle."
Meanwhile, Europe is pursuing a different "clean coal" technology for power generation called oxy-fuel combustion, in which the coal is burned in the presence of mostly oxygen, outputting a pure stream of carbon dioxide that is easily captured, compressed and injected underground, according to Kevin Whitty, an associate professor of chemical engineering with the University of Utah's Institute for Clean and Secure Energy. In Germany, a fully integrated demonstration plant and carbon storage facility is under construction.
Whitty is "optimistic, but not necessarily hopeful" for gasification's prospects.
"It's getting over that big hurdle of having a few successful demonstration plants," he said.
The main reason gasification has remained on the chalkboard is the unlevel playing field enjoyed by existing facilities, Baxter argues. Most of the cost of generating power stems from the construction of power plants.
"That's why we have such old power plants," Baxter said. "Once a plant is paid off the cost of generation goes way down. And the old plants don't face the same regulatory pressure regarding emission standards."
As society puts a greater premium on reducing harmful emissions, however, the cost of conventional power will soar as industry makes new investment to comply with future restrictions, he predicted.
"The rest of the developed world is working on it and is making progress," Baxter argued. "We are mostly in denial in the United States. There's no doubt that carbon dioxide concentrations in the atmosphere are increasing, man is causing that increase, and that increase is changing the climate."
Under current economic models, power produced by gasification is 30 percent higher than conventional coal-fired model, about 6 cents versus 8 cents per kilowatt hour. Add carbon dioxide capture and storage, however, the cost goes way up for both models, but the cost differential disappears because gasification simplifies the process of sequestering this major greenhouse gas.
"It's still going to be more expensive than current techniques, but it will be cost-competitive compared with most other processes that include CO2 capture and storage," Baxter said. "Coal gasification in the future could become as important as coal combustion is to us right now."
-- BRIAN MAFFLY can be contacted at bmaffly@sltrib.com" Target="_BLANK">bmaffly@sltrib.com or 801-257-8605.