Technology Update: Detoxifying anti-NOX technology

Carter, expects that the cables will prevent 400 kilowatts of ... the streets Carter says. Almough technologies ... said that every country in the wor...
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nology development. When the installation is complete in July 2002, the technology will enable the existing transmission lines to carry 240 MW of additional electricity. Later this year, superconducting transmission cables will be demonstrated at Detroit Edison, which is installing tire cables at its Frisbee power substation in Detroit, Mich., as part of a Department of Energy (DOE) demonstration. Because these cables nearly eliminate electrical resistance to the flow of current, they conduct electricity much more efficientiy than traditional copper cable; the utility's director of transmission planning, Bill Carter, expects that the cables will prevent 400 kilowatts of power from being lost as heat each hour when they are operational this summer The design of superconducting cables is complex: They consist of thin metal tapes, which are immersed in liquid nitrogen to maintain their -196 °C temperature, tiien covered by an insulated cable. Despite die insulation, tiiey are much more compact than copper cables. Because three superconducting cables can move as much electricity as nine conventional cables while taking up far less room, Detroit Edison should be able to expand its capacity to meet die city's resurging needs—two new stadiums are being built downtown—without digging up the streets Carter says Almough technologies like FACTS and superconducting cables have benefited from investments in research and development over the preceding decades, funding for some of the long-term technologies on EPRI's roadmap—such as the technologies tiiat could result in hydrogen-based metiiods of generating electricity by 2050—is in jeopardy, Yeager stressed in his October briefing. Because of the huge projected increases in worldwide demand for electricity by 2050, the world faces a "policy trilemma" in the coming century, Yeager explained. Electricity generation policies will have to balance three conflicting requirements: a drastically increasing population; an expanding appetite for electricity in the developing world where much of the growth will take place; and the pollution implications of using electricity-generating technology he said. Because both federal and utility investment in energy technologies has

Utility R&D is declining fast Utility investment in research and development has been declining in recent years. Annual R&D investment is shown in millions of dollars.

dropped off in die last decade, Yeager said that every country in the world should gready increase funding to develop technology that will reduce the environmental impacts of electricity use. He called on die United States to spend at least $5 billion more per year on research and development. And Cavanaugh, Wilhelm, and Yeager all expressed concerns that the increased focus on short-term profits expected to result from deregulation could derail that gready needed investment. —KELLYN S. BETTS

Detoxifying anti-NOx technology Removing oxides of nitrogen (NOJ from coal-fired power plants' smoke requires vast amounts of ammonia. A new technology able to quickly fabricate the highly toxic and hazardous chemical allows utilities to reduce die risk associated with storing and using ammonia. Controlling NOx emissions from a typical plant's 500-MW boiler using selective catalytic reduction— which EPA considers the best achievable control technology—requires 2000 lb of ammonia per hour, which equates to millions of pounds of die chemical per year, said Hamilton Walker, director of NO control marketing and sales for Environmental Elements Corp., a company selling the new technology. Because of ammonia's volatile nature the Clean Air Act requires many utilities that store it to file risk management plans with EPA. The new technology, called Ammonia on Demand, uses nontoxic urea as the basis for producing ammonia. Developed by Hera LLC of

Orange County, Calif., and Siirtec Nigi of Milan, Italy, the ammoniagenerating system dissolves the urea in water, then produces the gaseous form of ammonia needed by the selective catalytic reduction equipment by hydrolysis. Walker acknowledged that his company's new technology is "significandy" more expensive than the equipment tiiat is required to store ammonia in its pressurized anhydrous form, which is mainly used in more rural locations because of safety concerns. But the new technology's capital costs will be offset by saving anhydrous ammonia users from the costs associated with maintaining risk management plans and associated safety training programs Walker said. The other option for utilities is aqueous ammonia. Depending upon its concentration, the ammonia may not trigger EPA risk management planning requirements. In fact, many cities require utilities to use the aqueous form because it is much safer to store, said Jeff Clark, director of policy and communications for EPA's Office of Air Quality Planning and Standards. Environmental Elements Corp.'s calculations show tiiat the Ammonia on Demand system costs per ton are roughly the same as for aqueous ammonia, Walker said. The need to transport aqueous ammonia to utilities can spark community opposition to its use, however. Local resistance to having four ammonia-laden trucks travel through Cape Cod each week to clean up a 540-MW boiler's emissions inspired Soutiiern Energy, Inc, to become the first utility to purchase die Ammonia on Demand technology said Dean Brunton project manager for the company Because coal-fired power plants' emissions of nitrogen oxides— which contribute to ground-level ozone, acid rain, and eutrophication—have grown 40% since 1970, the increased use of NO control technologies by utilities is "inevitable", according to Clark. No matter what the fate of the disputed EPA Clean Air Act regulations that require 22 states to reduce their NO emissions, Clark said both EPA and the individual states are "only going in the direction of more control for nitrogen oxides from large power plants." KELLYN S. BETTS

JANUARY 1, 2000 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS • 3 7 A