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Show BACKGROUND Advances in emission control techniques at reduced costs and auxiliary power requirements, coupled with significant improvements in steam turbine and cycle design, have significantly altered the governing criteria by which advanced technologies have been compared. In the late 1980s it was commonly believed that coal-fired power plants of the future would incorporate either some form of Integrated Gasification Combined Cycle (IGCC) or fust generation Pressurized Fluidized Bed Combustion (PFBC) technologies. However, the recent advancements have indicated that pulverized coal technology can continue to be competitive in both cost and performance for at least the next decade. In the early 1990s it appeared that if IGCC and PFBC could achieve costs comparable to conventional pulverized coal (PC) plants, their significantly reduced NOx and S02 emissions would make them more attractive. A comparison of current emission control capabilities shows that all three technologies can already achieve similarly low emissions levels (see Figure 1). Figure 2 shows that by developing the technologies required to improve the steam conditions in a PC plant, cycle efficiency differences can also be mitigated. In fact, driven by emissions regulations in Europe and fuel costs in Japan, advanced pulverized coal fired plants are already being built with ultrasupercritical steam conditions which will achieve net plant efficiencies exceeding 40% [higher heating value (HHV)] with very low emissions. Development has progressed in Japan and Europe due to high fuel costs and low emissions requirements. Though present emissions limits (NSPS), fuel costs to the generating company and legislation, such as fuel adjustment clauses, do not currently justify high efficiency or extremely low emissions technologies domestically, it is clear that this is likely to change. In recognition of the competitive potential for advanced PC systems with other emerging advanced coalfued technologies, the DOE's Pittsburgh Energy Technology Center began a research and development S02 & NOx emissions, Ibs/MWh 8 7 6~~~~~~~~~~~~--~ 5~~-----+--------r--------1 4 3 2 1 O~~~~~~~~~~~~~~ PC wlFGD + SCR PFBC IGCC FIGURE 1 CURRENT EMISSIONS FROM COALBASED TECHNOLOGIES 2 10 !'# 9~ --IGtCCl ----;:---------PlFBC- ------- ~ 4 1 ooctl1 025"11050· 'i S 1050"11050· ~ Cunwnt 1 050"11 ooct • 2 Technology i: _______ L__ 1500 2400 FIGURE 2 Main ateam prMaUre, ~I NETPLANTER8CIENCYCOAL TECHNOLOGIES 5000 |