Effect of generating unit age on the cost and performance of US fossil-fired steam units. Phase one report, Estimating the effect of generating unit age on the performance of coal-fired steam units.

摘要

The purpose of Phase 1 of this study is to quantify the effect of age on the performance of coal-fired units in the absence of life extension/betterment programs (i.e., beyond normal maintenance). Time-series cross-sectional unit-level data for the period 1964--1987 were used to estimate regressions relating the effect of age on equivalent forced-outage rate (EFOR), equivalent availability forced (EAF), and heat rate (HR). A sample of electric generating units representing about two-thirds of total US coal capacity in 1987 provided the basis for the regressions. The sample included roughly 570 subcritical units accounting for 5600 unit-years and 150 gigawatts (GW) and 100 supercritical units accounting for 1000 unit-years and 70 GW. An important feature of the study was to develop one model for both subcritical and supercritical units to control for various operating and design characteristics, and to profile the aging pattern of these units. The econometric models developed controlled for the effects of: age, capacity, design vintage or generation of design, boiler and furnace design, rest-of-plant design, coal quality, duty cycle, and life extension and plant betterment investments. The impact of life extension and plant betterment investments on the aging effect was controlled by identifying when their effect on operations and maintenance expenditures increased and by terminating the time-series analysis in that year. 6 refs., 8 figs., 12 tabs.