Evidence is mounting that power plant cycling is causing significant additional wear and tear on the units. However, the effects of this additional wear and tear on future maintenance costs, production cost, and equivalent forced outage rate (EFOR) are not accurately quantified at the present time. For example, units that were originally designed for base load operation are now being cycled by many utilities. Typically, such units experience long-term decreases in availability and significantly increased maintenance and capital equipment expenditures because several materials degradation phenomena (creep, fatigue, creep-fatigue interaction, etc.) are accelerated by increased cycling.
The authors will present results of several hundred studies, which highlight the impacts of plant cycling events on short and long term plant availability. The paper will also show the impact of plant cycling design, annual capital and operating expenses which can have a direct impact on plant availability.