Power uprating for nuclear generating stations

Thermal power uprating is a viable means to increase the electrical generation of a nuclear station in a safe and cost-effective manner. Most nuclear stations have the capability for thermal power upratings of 5 to 8% [35 to 75 MW(e)] without major hardware modifications or significant plant downtime. Within this range, an uprating program is primarily analytical in nature and consists of demonstrating continued compliance with design codes, standards, and functional requirements currently applicable to each specific plant. An uprating can be implemented in <3 yr and requires a low capital investment. The estimated total cost of uprating a unit by 5 to 8% is $100 to $400/kW(e). Upratings >8% are also feasible. In general, however, significant modifications to the plant are necessary for upratings in this range (such as to the steam turbine, electrical generator, feedwater system, steam system). A number of utilities have already performed thermal power upratings. These upratings include plants designed by various nuclear steam supply system suppliers and architect/engineers, plants ranging from <500 MW(t) to >3400 MW(t), plants in various stages of design or already in operation, and both domestic and foreign plants. This broad spectrum of accomplished upratings indicates that any nuclear station can be considered as an uprating candidate at any time in its life cycle