The objective of this report is to establish a database of costs associated with operating a circulating fluidized bed boiler for electric power production in a utility environment. Such data and information can be used by others for resource planning and for comparisons with competing technologies. Costs are also presented for the engineering, construction and start-up of the Nucla CFB. These are compared with estimates made in 1981 prior to completing detailed engineering. Detailed monthly operating costs over the testing period covered by the Cooperative Agreement, from September 1988 through January 1991, are presented in Appendix D. An overall summary of cost data for this period is presented in the same format in Appendix C. These data were generated by CUEA using reporting requirements established by the Rural Electrification Administration`s Uniform System of Accounts. This accounting system is consistent with that used by the Federal Energy Regulatory Commission`s Uniform System of Accounts, which is prescribed for public utilities and licensees subject to the provisions of the Federal Power Act. The definitions of terms used in the REA code of accounts are contained in Appendix B.