Talk:Small modular reactor

Renewed interest

How does the random research and development of a 400 MWe and a 100 MWe reactor in the 80s have anything to do with the history of SMRs and doesn't meet the authoritative definition of an SMR? You can't just add a bunch of R&D info on nuclear reactors that have nothing to do with what is globally defined as an SMR to build a case that SMRs are nothing new. Clearly, that's what we all see is going on in this section. This Section has nothing to do with SMR history or SMR R&D. Definition: https://www.iaea.org/newscenter/news/what-are-small-modular-reactors-smrs

Oregon State University had been researching how to develop a new modular reactor since the late 1990s: https://neup.inl.gov/content/uploads/14/2024/07/NuScale-Power-Success-Story-Final.pdf

2009 mention of SMR by Reyes: https://www-pub.iaea.org/MTCD/publications/PDF/P1500_CD_Web/htm/pdf/plenary/17KS_Reyes%20_PM.pdf

A document predating 2010 using SMR: https://www-pub.iaea.org/MTCD/publications/PDF/P1500_CD_Web/htm/pdf/plenary/17KS_Reyes%20_PM.pdf

This was years before the federal government began its program. "In 2007, NuScale Power Inc. was formed to commercialize the concept and MASLWR was renamed the NuScale plant to reflect the significant improvements made to the original design. In early 2008, NuScale Power Inc. notified the US NRC of its intention to begin pre-application discussions aimed at submitting an application for design certification of a 12 module NuScale power plant. NuScale Power Inc. plans to submit design for certification by the US NRC. This effort is aimed at deploying NuScale plants to address the near term needs of the US utility market."

None of this is covered in this section and ALL US nuclear agencies recognize NuScale as the first patented and approved SMR. Why is this not the most important part of this section? Ludviggy (talk) 01:31, 3 May 2026 (UTC)

That section is describing the events leading up to the development of modern SMRs, which is why it is under the 'Background' heading. It describes how the concepts of inherent safety, modularity, and deliberately small reactors evolved over time. The 400 MW (PIUS) and 100 MW (MHTGR) designs are relevant background information because they influenced modern SMR designs. One of the sources used in the article, Daniel Ingersoll's book Small Modular Reactors, explicitly cites the PIUS design:

"Although larger than modern SMRs, which mostly have capacities below 300MWe, the PIUS design influenced subsequent SMR designs through its innovative approach to ensuring long-term cooldown of the reactor."

None of the sources you just provided describe NuScale as the first "patented and approved" SMR. Instead, they talk about how its design came from the government's MASLWR program, part of the DOE's 1999 Nuclear Energy Research Initiative (NERI). Indeed, the entire 'Renewed interest' section explicitly discusses the MASLWR program, and mentions that it was turned into NuScale's reactor: One concept, the IRIS SMR, would later receive significant commercial interest and funding under the GNEP, while another, the MASLWR, later formed the basis for NuScale's SMR. Similarly, the fact that NuScale's design was the first SMR design in the United States to receive a Standard Design Approval is already mentioned multiple times throughout the article.

As for the government's SMR program, the line In 2012, the DOE began its SMR program in earnest, by which point interest in SMRs was significant is talking about the DOE's explicit SMR-focused program, which began in 2012. This section does not claim that government support for SMRs began in 2012, rather that it significantly increased at this point. The section, again, already discusses the NERI and other earlier programs:

The DOE also ran an Advanced Liquid-Metal Reactor program, which led to the development of the General Electric Power Reactor Inherently Safe Module (PRISM) SMR in the 1980s and 1990s.

However, in 1999 the DOE began the Nuclear Energy Research Initiative (NERI), followed by the Generation IV International Forum in 2000, and later the Global Nuclear Energy Partnership (GNEP) in 2006. The NERI program resulted in the development of multiple SMR designs, including liquid metal-cooled reactors and SMRs designed for process heat, as well as others based on existing LWR technology.

Finally, the article doesn't describe the term "SMR" as being created in 2010. It simply states, with a source directly supporting this claim, that Steven Chu's 2010 article brought it into wider use, and codified "SMR" as referring to "small modular" reactors as opposed to "small and medium-sized" reactors. H2so4aq (talk) 03:39, 3 May 2026 (UTC)

Source 1: https://www.energy.gov/ne/articles/nrc-approves-first-us-small-modular-reactor-design

Source 2: https://patents.justia.com/patent/10672528 (A granted patent means they are the first. If you read the patent in its entirety, you will realize this matches the definition of an SMR as previously provided.)Ludviggy (talk) 05:06, 3 May 2026 (UTC)

As @EducatedRedneck: made clear in our previous discussion, a patent can't be used to prove that someone did something first; that's WP:OR. We can't expect the reader to comb the patent inventory to verify that this is the first patent related to this technology. This is a WP:REHASH of our previous discussion.

Separately, I see you updated the "Disputed" template on the article section. Can you elaborate on what part of the section you are disputing? I already replied to your comments about PIUS and MHTGR, and clarified that the section already contains significant coverage of the NERI and MASLWR programs. Are you saying this information is factually wrong? Or that you think this section should give more WP:WEIGHT to NuScale? Please explain clearly what your issue is.

Daniel Ingersoll, whose book Small Modular Reactors: Nuclear Power Fad or Future? I used as a source for a significant portion of the Renewed Interest section, was NuScale's Director of Research Collaboration and in fact is the first name listed on the patent you referenced. At no point does he argue, in his two chapters on the history of SMRs, that NuScale was the first SMR or the first patented SMR, or that they invented a significant part of the basic concept of an SMR or multi-module plant. His book says that SMR designs and concepts (inherent safety, multiple small modules, etc.) evolved over time from earlier reactors like PIUS and MHTGR, into early SMRs like the PRISM SMR, and then into the IRIS and MASLWR/NuScale integrated LWR designs.

Finally, I have found multiple sources backing up the inclusion of the PIUS design, as well as the idea that SMR designs were being developed progressively before NuScale's. The book Nuclear Power Reactor Designs (2023, ) explicitly states, "However, despite the recent interest in SMRs, the concept is not novel." Similarly, Chapter 20 (Small Modular Reactors) in the Handbook of Generation IV Reactors by Fatih Aydogan explicitly references the 400 MW PIUS design as having heavily influenced modern SMRs. Chapter 1 of the same book also states that, "PWRs-KLT-40s SMRs are the first SMRs in the world (connected to grid in December of 2019) have overheated steam at the high-pressure turbine inlet, but no reheat of secondary steam." H2so4aq (talk) 23:09, 5 May 2026 (UTC)

Ludviggy, I am seeing today the same arguments you made last month. Please drop the stick and stop WP:BLUDGEONing; it is disruptive. EducatedRedneck (talk) 01:04, 6 May 2026 (UTC)

Completion 2026/2027

"The project is estimated to be completed by 2026–2027" - is this still current? Rebentisch (talk) 17:29, 4 July 2026 (UTC)

Good catch. None of the listed sources actually provided that date. I've updated the section to mention that the target date as of 2026 is 2033. H2so4aq (talk) 22:14, 5 July 2026 (UTC)