ERG completed a power supply study performed for a joint action agency consisting of 18 municipal utilities located in the Southeastern U.S. The study assessed the viability of repowering aging gas-fired conventional boilers at 6 municipal power plants, and compared potential combined-cycle repowering opportunities, with new greenfield power plant development, and merchant power offers.
Seventeen units at six sites were identified as candidates for repowering. The units ranged in size from a low of 5 MW to a high of 41 MW, and in age from 27 years to 40 years. As part of the analysis, ERG staff visited and reviewed the selected facilities, assessed the candidate equipment, and developed estimated cost and performance parameters for each of the repowering options.
In addition to assessing the technical feasibility of the repowering options, and in order to compare the repowering opportunities with competing alternatives, ERG performed a system wide economic analysis. The analysis involved forecasting member utilities loads and fuel prices, and forecasting the availability of, and prices for wholesale market power. As part of the study, the utilities existing generating system was modeled for comparison to potential supply-side options. Total production costs for the system were developed and compared under various operating and capacity expansion scenarios. Study results were used by the agency in support of its future supply decision making.