"PRS-23." Prepared in cooperation with Tennessee Valley Authority, Office of Power, Chattanooga, Tenn., under interagency agreement no. EPA-IAG-D5-E721, program element no. EHE623A, for U.S. Environmental Protection Agency, Office of Research and Development. "Nov. 1977." "EPA/600-7-77-126." Includes bibliographical references (leaf 318).

A conceptual design, performance and cost comparison was completed for utility-scale (750-925 MWe) coal-burning power plants employing three alternative technologies: (1) conventional boiler with a stack gas scrubber (CWS); (2) atmospheric-pressure fluidized-bed combustion (AFB); and (3) pressurized fluidized-bed combustion; combined cycle (PFB). The AFB and PFB designs; estimates used were those completed by the General Electric Company team as part of the Energy Conversion Alternatives Study (ECAS), funded by NASA, ERDA and NSF. The CWS designs/estimates were developed by the GE team for the study reported here, using the same basis as was used for ECAS. TVA modified and expanded the GE results to: (1) reflect TVA costing experience and include an uncertainty allowance for undermonstrated technology; (2) consider alternate wet scrubbing techniques for the CWS, including lime scrubbing, limestone scrubbing and magnesium oxide scrubbing; and (3) include solid waste disposal costs for all three plants for a 30-year lifetime, and assess alternative disposal options. The reults suggest that: (1) AFB offers a possible savings of 9 to 14 percent in the cost of electricity (COE) in comparison with CWS, and PFB offers a savings of 0 to 7 percent, depending on whether or not an uncertainty allowance is applied; (2) hot gas cleaning and pressurized solids handling in the PFB are major contributors to the COE (the cost of these items can very significantly if different design conditions are assumed), offsetting the savings resulting from PFB's greater energy efficiency; and (3) application of alternate scrubbing techniques does not affect the economics of CWS enough to significantly change its position relative to AFB AND PFB. When uncertainties are included, the estimated COE for the three alternatives is so close that all are considered to be within the competitive range for further consideration.