THE BIG PICTURE: Small Modular Reactors

Interest in small modular reactors (SMRs) has ramped up of late owing to applications in niche electricity or energy markets where large reactors would not be viable—such as for cogeneration in countries with small grids, remote and off-grid areas, and for nuclear/renewable hybrid projects.

Modular attributes may also enable SMRs to target the economics of serial production, offering shorter construction timeframes. But though significant advancements have been achieved for more than 50 key SMR technologies worldwide in recent years, most continue to crawl through the development pipeline. Source: International Atomic Energy Agency’s (IAEA’s) Advanced Reactors Information Systems (ARIS) database 


Technology Types

Land-based water-cooled SMRs: Designs that adopt integral light water reactor (LWR) technologies.

Marine-based water-cooled SMRs: Concepts that can be deployed in a marine environment.

High temperature gas-cooled (HTGR) SMRs: Modular-type designs that provide heat of more than 750C.

Fast neutron spectrum SMRs: Designs with fast neutron spectrum and an assortment of coolant options. These include sodium-cooled fast reactors (SFRs), heavy liquid metal-cooled (HLMC) fast reactors, and gas-cooled fast reactor (GFRs).

Molten salt SMRs. Designs that are fueled and cooled with molten salt.

Other SMRs. SMRs that cannot be classified in other categories.

—Copy and artwork by Sonal Patel, a POWER associate editor (@sonalcpatel, @POWERmagazine)