NuScale Power Corporation is a publicly traded American company that designs and markets small modular reactors (SMRs). It is headquartered in Tigard, Oregon. The company's VOYGR power plant, which uses 50 MWe modules and scales to 12 modules (600 MWe), was the first SMR to be certified by the US Nuclear Regulatory Commission (NRC) (2022). The newer 77 MWe module designs, known as the VOYGR-4 (308 MWe) and VOYGR-6 (462 MWe), were submitted for NRC review on January 1, 2023, and approved May 29, 2025. NuScale is now seeking NRC approval for their 12-module, VOYGR-12. The SMR is also scalable, offering up to 924 MWe.

NuScale Power Modules are surrounded by a 9 feet (2.7 m) diameter by 65 feet (20 m) tall reactor vessel that relies on conventional cooling methods. The modules run on low enriched uranium fuel assemblies based on existing light water reactor designs. For a 12-module configuration, the modules are stored individually in submerged storage wells on the floor of a shared 75-foot deep, 10-million-gallon reservoir, and covered by a concrete barrier. A natural convection coolant loop is relied upon to feed all of the modules used in a plant. The patented system is capable of delivering additional fresh water to each reactor vessel without powered pumps in the event of an emergency.

NuScale had an agreement to build reactors in Idaho by 2030, but it was canceled in 2023 due to the estimated cost having increased from $3.6 billion to $9.3 billion for the original VOYGR power plant. As of 2025, the company has a number of contracts under negotiation around the world, including Romania and Tennessee. More SMR interest has come from tech giants who are looking to power US-based data centers. NuScale's design is the only approved design for use in the US.

NuScale was founded based on research conducted by a team of nuclear scientists at Oregon State University (OSU) and the Idaho National Laboratory (INL) and funded by the United States Department of Energy (DOE) beginning in 2000. OSU researchers, headed by José N. Reyes Jr. developed a prototype SMR in 2007, which NuScale Power used to develop its prototype. Much of the research was performed at OSU's Multi-Application Small Light Water Reactor (MASLWR) test facility starting in 2007, with full-scale prototype testing performed in Idaho at the INL in 2013. DOE funded the research from 2000 to 2003.

The same year Oregon State University constructed its one-third-scale reactor test facility (MASLWR), the university founded NuScale Power. Joint research between OSU and NuScale soon followed. As compensation for past research, OSU offered researchers opportunities to exchange patents for an equity stake in the new company. NuScale's first round in funding came in January 2008. The next month it began seeking certification with the NRC.

By 2011, NuScale had raised $35 million and had 100 employees in Tigard; Richland, Washington; and Corvallis, Oregon. NuScale was the first to submit small reactor plans to the NRC and the first to gain approval. It was evaluated by a consortium of utility companies called Energy Northwest.

In January 2011, NuScale's largest investor, Kenwood Group, was investigated by the U.S. Securities and Exchange Commission (SEC) and later pleaded guilty to operating a Ponzi scheme. The SEC investigation was not related to Kenwood's dealings with NuScale, but Kenwood's assets were frozen just as NuScale was expecting additional funding. The company started making staffing and pay cuts as executives looked for new funding sources and most of the company's employees were laid off.

That September, NuScale obtained a loan to re-hire 60 employees. In October, Fluor Corporation acquired a majority interest in the company for $3.5 million and promised almost $30 million in working capital. According to The Energy Daily, Fluor's investment saved the company, which had been "financially marooned" by its prior investor. A separate agreement gave Fluor the rights to construct NuScale-based power plants.