Small Modular Reactors (SMRs): A New Generation of Nuclear Power?

 

 

Small modular reactors (SMRs) are small nuclear fission reactors that are partially factory-built and typically have a power output below 300 megawatts electric (MWe). They aim to make nuclear projects cheaper, enhance their safety, and open pathways to new business models. In a time of increasing energy uncertainty, approaching net-zero targets, and growing demand for reliable electricity from data centers, renewed interest in nuclear energy has emerged, particularly for SMRs.

 

The new IDTechEx report "Nuclear Small Modular Reactors (SMRs) Market 2026-2046: Technologies, Players, Benchmarking, Forecasts" provides a comprehensive account of the SMR market. The report is supported by 22 company profiles of key players across the industry, which are used to compare 10 different reactor technologies in a data-driven benchmarking scheme and provide a 20-year outlook for the growth of the industry, which could reach US$53.8 billion in 2036 and almost US$300 billion by 2046.

 

 

 

 

The design of the nuclear reactors used in SMRs can be split into two broad categories: "evolutionary" Gen III+ designs and "revolutionary" Gen IV designs. Gen III+ designs iterate on the successes of the widely deployed Gen III nuclear reactor types active today such as PWRs (pressurized water reactors) and BWRs (boiling water reactors). Meanwhile, Gen IV designs rethink the design of a nuclear reactor, using different fuel formats and thermodynamic cycles to offer improvements in performance, new capabilities, or enhanced passive safety features.

 

High-temperature gas reactors (HTGRs), liquid metal fast reactors (LMFRs), and molten salt reactors (MSRs) are the Gen IV reactor designs that are closest to deployment or already deployed on the market. One advantage that all three of these reactors have in common is a much higher operating temperature than most Gen III or III+ designs. While water-cooled reactors are designed to operate at most up to around 250-300°C, the proposed HTGR, LMFR, and MSR designs can reach much higher outlet temperatures, ranging from 500°C to well over 1000°C under normal operation. The key to reaching these higher temperatures is that in each case the primary coolant is not water, but a fluid better suited to very high temperatures: a gas such as helium for HTGRs, liquid metals like sodium or lead for LMFRs, and molten salts for MSRs.

 

According to the database of over 100 SMR projects gathered by IDTechEx for the newest SMR market report, both the average and maximum coolant outlet temperature of every type of Gen IV reactor is higher than any type of Gen III+ reactor. Higher operating temperatures not only improve the thermal efficiency of the SMR but also open avenues to industrial processes that can directly make use of high-temperature process heat such as in steelmaking, chemical manufacturing, or thermochemical hydrogen production.

 

 

 

Despite the seemingly "next-generation" name, it's worth noting that design concepts and test reactors for the Gen IV reactors discussed here have existed for decades. In the current industry, dominated by large nuclear power plants, reactor technologies converged largely on water-cooled reactors. However, technology innovation through SMRs has allowed HTGRs, LMFRs, and MSRs to receive renewed attention.

 

In the United States, prominent SMR startups developing Gen IV designs include Oklo, X-Energy, and Kairos Power, each backed with funding from tech giants like Meta, Amazon, and Google, as well as renewed government support for advanced nuclear projects. Meanwhile, China National Nuclear Corporation (CNNC) made history by completing the world's first commercial Gen IV SMR back in 2022 - a pebble bed HTGR known as HTR-PM that can output 100MW electrical.

 

All this considered, the Gen III+ SMR designs developed by the likes of NuScale, Rolls-Royce SMR, and GE-Hitachi are still highly competitive and being closer to well-established nuclear technology could benefit them greatly when scaling up the rollout of SMR power. By amassing a database of over 100 SMR projects active globally, IDTechEx has evaluated 10 different reactor technologies in a quantitative benchmarking scheme, comparing different reactor types by their most important economic and technical metrics in the new SMR market research report, "Nuclear Small Modular Reactors (SMRs) Market 2026-2046: Technologies, Players, Benchmarking, Forecasts".

 

 

Between a growing market for nuclear in Asia, changing policies in Europe, renewed investments in North America, and potential future markets in Africa and South America, the global market landscape for SMRs is complex but rife with opportunity.

 

 

For more information on this report, including downloadable sample pages, please visit www.IDTechEx.com/SMRs, or for the full portfolio of energy research available from IDTechEx, see www.IDTechEx.com/Research/Energy.