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CO2 storage is feasible, but permanence of storage is in question.

The urgency in implementing policy change and technological advances in limiting emissions of carbon dioxide rang out from two recent conferences on related technology, carbon capture and advanced clean-coal combustion. Calls for action on carbon capture and sequestration came equally from an environmental advocate and industry representatives and were echoed from the conference floor, all galvanized by the change in public attitudes toward global warming that has overtaken the U.S.

“This Congress in this session should declare as a matter of policy that no new coal plants will be built in the United States unless the carbon is captured,” said David Hawkins, climate center director for the Natural Resources Defense Council, New York City, to the sixth annual Conference on Carbon Capture & Sequestration, held May 7-9 in Pittsburgh. “Even a badly leaking early-storage program will allow far less emission than one started in 2031 after thorough testing and proof.”

“At the end of the day, large industrial customers will buy into high costs [for electricity generated with CCS] because this is a societal issue,” said Michael G. Morris, chairman, president and CEO of American Electric Power Co., Columbus, Ohio. But the success of industrial-scale CCS will depend largely on new public policy, said Elizabeth Cheney, vice president of corporate support for Shell Exploration & Production Americas, Houston. Attendees expressed concern about issues such as liability for failed storage, which policy clarity would settle.

A separate conference, also in Pittsburgh, on integrated gasification combined-cycle power generation (IGCC) followed the carbon-capture conference and shed further light on some common issues. The U.S. Environmental Protection Agency is working on models to assess the economic viability of IGCC plants under different conditions, said Sam Napolitano, EPA’s clean air markets director, addressing Platts third annual IGCC Symposium. Like ENR, Platts is a unit of the McGraw-Hill Cos.

A principal selling point of IGCC has long been that it is the only technology that makes capture of carbon dioxide economically feasible (ENR 6/20/05 p. 16). But there’s no consensus yet on that, says Mark Langford, vice president of business development at Kiewit Industrial Co., Lenexa, Kan. Some speakers at the CCS conference insisted that conventional pulverized-coal-fired powerplants with postcombustion CO2 capture can no longer be built and that IGCC commercialization must be accelerated. Others claimed carbon capture could be cost-effectively retrofitted onto PC plants.

“The serious challenge is the postcombustion retrofit technology,” said AEP’s Morris. “It will give the existing fleet a fighting chance to stay in business.” Texas-based utility TXU’s recently aborted program to construct eight supercritical “capture-ready” PC plants, which reserved space for future carbon-capture equipment, seems to have foreclosed construction of coal-fired plants without carbon capture. But “capture-ready with space considerations is true,” insists Langford.

“The key message is that costs for IGCC are much higher than people expected,” says Gary Stiegel, gasification technology manager for the National Energy Technology Laboratory, Pittsburgh. But concern about CO2 emissions is increasing pressures to develop a carbon-neutral power generation technology. Ultimately, stakeholders must find the balance between appropriate study and effective answers to the problem.