SMR Technology Overview

Introduction to Small Modular Reactors

Small Modular Reactors (SMRs) represent a new generation of nuclear power plants that are designed to be manufactured at a plant and transported to a site for assembly. With power capacities ranging from 10 to 300 megawatts electric (MWe), they are significantly smaller than conventional nuclear reactors which typically exceed 1,000 MWe.

Key Technological Features

Modern SMR designs incorporate several advanced features that distinguish them from traditional nuclear plants:

Passive Safety Systems

Unlike conventional reactors that may require active intervention during emergencies, many SMR designs incorporate passive safety features that rely on natural forces like gravity, natural circulation, and convection to maintain cooling in case of power loss or other emergencies.

Modular Construction

SMRs are designed for factory fabrication with standardized components, allowing for higher quality control, reduced construction times, and lower capital costs. Modules can be transported to sites via truck, rail, or barge.

Scalable Deployment

Multiple SMR units can be installed incrementally to match growing energy demands, reducing initial capital requirements and financial risks compared to large conventional plants.

Reduced Exclusion Zone

Enhanced safety features allow for smaller emergency planning zones, making SMRs suitable for locations closer to population centers or industrial facilities.

Leading SMR Technologies

Several SMR designs are in advanced stages of development or early deployment:

Light Water SMRs

These use conventional water cooling and uranium fuel, similar to existing nuclear plants but with innovative safety features. Examples include NuScale's 77 MWe module and GE-Hitachi's BWRX-300.

High-Temperature Gas-Cooled Reactors

Using helium as coolant and graphite as moderator, these reactors operate at higher temperatures, enabling more efficient electricity generation and potential industrial heat applications.

Liquid Metal-Cooled Fast Reactors

Using sodium or lead as coolant, these designs can utilize fuel more efficiently and potentially consume existing nuclear waste as fuel.

Molten Salt Reactors

These innovative designs use liquid salt as both coolant and fuel carrier, offering inherent safety features and efficient operation.

Applications for Developing Regions

SMRs offer particular advantages for developing nations and island communities:

• Right-sized capacity for smaller grids without destabilization risks
• Reduced water requirements compared to conventional plants
• Ability to replace diesel generators with minimal grid modifications
• Potential for desalination and industrial heat applications
• Lower initial capital requirements and phased investment approach

Deployment Timeline

Several SMR designs are expected to be commercially available within this decade:

• NuScale (USA): First commercial deployment expected 2029-2030
• BWRX-300 (USA/Japan): First unit under construction in Canada
• RITM-200 (Russia): Marine version operational, land version in development
• ACP100 (China): First unit connected to grid in 2023
• UK SMR (Rolls-Royce): First unit planned for early 2030s