How it works - Integral reactor designs do not include external piping and flow paths that may be used in traditional PWR reactor systems for controlling or directing flow of coolant through the core under off-normal conditions. In particular, during scenarios which result in partially filled systems, current Pressurized Water Reactors (PWR) designs must prevent buildup and precipitation of boron crystals at the outlet of the core region by “back flushing” the system through special alignment of the piping from the steam generator to the reactor coolant pump and back to the reactor pressure vessel (called the “cold leg”) and piping between the reactor pressure vessel and the steam generator (called the “hot leg”). Since NuScale Power Modules incorporate integral systems and they do not have these external large reactor coolant piping systems, other methods of ensuring coolant circulation are needed. The patent granted to NuScale provides a patented method for providing this important coolant circulation in integral systems.
Recently, NuScale announced a major technological breakthrough whereby the NuScale Power Module does not require any operator action, electrical power—alternate current (AC) or direct current (DC)—nor additional water beyond system inventory, to be able to achieve safe cooldown in a station blackout condition.
About NuScale Power, LLC
NuScale Power is developing an inherently safe, modular, scalable commercial nuclear power technology. Fluor Corporation (NYSE: FLR), a global engineering, procurement and construction company with a 60-year history in commercial nuclear power, is the majority investor in NuScale. NuScale's design offers the benefits of carbon-free nuclear power but takes away the issues presented by the cost of installing large capacity. A nuclear power plant using NuScale's technology is comprised of individual nuclear power modules; each produces 45 megawatts of electricity with its own combined containment vessel and reactor system, and its own designated turbine-generator set. A power plant can include as many as 12 NuScale integral PWR modules to produce as much as 540 megawatts. The reactors are cooled by the natural convection of water and can be shut down safely without pumps or other mechanical systems. NuScale power plants are scalable - additional modules are added as customer demand for electricity increases. NuScale's technology also is ideally suited to supply energy for district heating, desalination and other applications.