13. Advanced Nuclear Reactors (Small Modular Reactors & Beyond)

Purpose:

Develop a new generation of nuclear fission reactors that are safer, more affordable, and more flexible than traditional large reactors. Advanced reactors include Small Modular Reactors (SMRs) and other innovative designs (using alternative coolants like molten salt, liquid metal, or gas, and fuels like high-assay low-enriched uranium or thorium). The goals are to provide reliable low-carbon energy with enhanced safety (using passive cooling, etc.), to serve smaller markets or grids (with modular units producing tens to a few hundred MW instead of 1000+ MW), and to reduce construction times and costs via factory fabrication of modules.

Current Stage:

Several SMR designs are in late development and nearing deployment. In the U.S., NuScale Power’s 77 MWe light-water SMR design became the first to receive NRC design approval in 2020 carboncredits.com. NuScale plans to have its first plant (a 6-module VOYGR facility in Idaho) operational by the end of the decade, targeting ~2029–2030 for deployment nuscalepower.comcarboncredits.com. The U.K. is pursuing the Rolls-Royce 470 MWe SMR (a scaled-down PWR) aiming for first unit by early 2030s carboncredits.com. Rolls-Royce has government backing and expects to build at least three SMRs in the UK by 2030s ans.org.

Other notable SMRs: Canada’s Ontario is preparing to build a GE Hitachi BWRX-300 (300 MWe boiling water SMR) at Darlington by 2028, which would be among the first grid-connected SMRs in the West carboncredits.com. GE Hitachi has multiple customers lined up (in U.S., Poland, Sweden). China has already connected a small (200 MWe) ACP100 SMR (Linglong One) to the grid in Hainan in 2021–2023 timeframe – the world’s first operational SMR, demonstrating the concept carboncredits.com. Russia has several small reactors, including floating nuclear plants (Akademik Lomonosov with twin 35 MWe units, providing power to remote regions).

Beyond water-cooled SMRs, advanced designs include: TerraPower’s Natrium (Bill Gates-backed, a 345 MWe sodium-cooled fast reactor with molten salt storage for flexible output, aiming demo by early 2030s) carboncredits.com; X-energy’s Xe-100 (80 MWe high-temperature gas reactor, pebble-bed design, targeting deployment in Washington state by 2028). Multiple prototypes will likely come online in the 2030s.

Key Players:

Companies – NuScale (USA), Rolls-Royce SMR (UK) carboncredits.com, GE Hitachi (USA/Japan) carboncredits.com, TerraPower (USA), X-energy (USA), Rosatom (Russia, with its RITM series reactors already on icebreakers and soon on land) carboncredits.com, CNEA (China National Nuclear Corp with Linglong One), and newcomers like Oklo (microreactor startup in USA). Countries – Canada, USA, UK, France, Russia, China, and Argentina (developing a small reactor CAREM) are notable. Government support is significant: e.g., U.S. Department of Energy is cost-sharing demonstrations of TerraPower and X-energy reactors. Poland and other nations with coal phase-out plans are looking to SMRs as replacement (multiple agreements signed in Eastern Europe). The International Atomic Energy Agency (IAEA) is facilitating knowledge exchange, and we see alliances like between U.S. and Romania for NuScale SMRs.

Potential Impact:

Advanced reactors could reinvigorate nuclear energy’s role in a clean energy future by tackling the issues that plagued traditional nuclear: high capital cost, long construction, and public safety concerns. SMRs, being modular, promise faster build times and lower upfront costs, making nuclear feasible for smaller utilities or developing countries that couldn’t finance a giant $10B plant. Factory fabrication and standardization (building reactors like assembling Lego) should also improve quality and reduce overruns.

Safety enhancements (many SMRs use passive cooling – they can cool themselves without power or human intervention in emergencies) aim to make accidents effectively impossible or negligible in impact. For instance, some designs are underground and use gravity and convection for emergency cooling. A meltdown in well-designed SMRs is extremely unlikely, and even in worst case, the smaller core and underground containment reduce risk to the public. This could help public acceptance of nuclear, which has been contentious post-Chernobyl and Fukushima.

In terms of energy strategy, SMRs can complement renewables by providing steady, carbon-free power and even load-following (some designs like Natrium integrate energy storage to ramp output when needed) carboncredits.com. They can be sited flexibly – closer to cities or industrial sites because of their smaller footprint and safety buffer requirements, or even on retired coal plant sites reusing the grid infrastructure. Remote regions that currently rely on diesel could deploy microreactors (a subset of SMRs, under 10 MWe) for reliable power (the U.S. military is testing a microreactor for remote bases by 2024).

Economically, countries leading in SMR tech might export reactors widely. The market is projected to be substantial by 2035 as many aging coal plants retire and need replacement with clean firm power. SMRs also open potential for non-electric applications: district heating for cities (as done in some Russian designs), desalination, hydrogen production (using high-temperature reactors for efficient electrolysis or thermochemical processes). For example, a high-temperature gas reactor could produce hydrogen with heat at higher efficiency than electrolysis.

Waste and proliferation: Many advanced reactors aim to be more fuel-efficient (burn more of the uranium, or even use spent fuel from old reactors as input). Some fast reactors could consume transuranic waste, reducing long-lived waste inventory – this could mitigate the nuclear waste issue if realized. Proliferation risk is considered low for SMRs if designed with sealed cores or infrequent refueling, but widespread global deployment means robust safeguards will be needed (e.g., IAEA monitoring).

By 2035, we might see dozens of SMRs in operation around the world carboncredits.com. If they deliver on promises, nuclear energy’s share could climb, aiding decarbonization goals especially for nations where renewables alone can’t meet demand reliably. In combination with fusion (if that arrives, albeit likely later), fission SMRs could hold the fort for carbon-free baseload until fusion matures, and even beyond.

SMRs will also test new business and regulatory models – perhaps private ownership of small reactors (even on corporate campuses for power) or novel insurance frameworks given different risk profiles. Community engagement will be key: a town might accept a 50 MW reactor under their hospital more readily than a giant plant on their skyline. If public and regulatory acceptance is achieved, advanced reactors could become a significant pillar of global energy, providing consistent clean power day and night and complementing wind, solar, and energy storage in a balanced, reliable grid.