Deployment of small modular reactors: A strategic roadmap validated by expert consensus

This paper develops and validates a strategic, phase-gate roadmap to support the deployment of land-based integral pressurised water reactor (iPWR) Small Modular Reactors (SMRs). While SMRs are frequently positioned as a pathway to enhance energy security and accelerate decarbonisation, deployment has been constrained by tightly coupled challenges across national institutions (policy, regulation and siting), technology and supply chain readiness, and project delivery and operations. For energy strategy, these constraints matter because long lead times, multi-actor coordination, and high irreversibility can undermine the credibility and deliverability of national plans if commitments are sequenced poorly. To address this, the study synthesises the fragmented SMR deployment literature into an integrated roadmap structured around three perspectives: the legal and institutional framework of the host country, SMR technology and supply chain, and nuclear project delivery and operationalises five major milestones as decision gates with objective completion criteria. The roadmap is validated through a structured, iterative expert process in which international practitioners reviewed successive versions for completeness, sequencing, and practical usability. The resulting roadmap functions as a decision-support tool for policymakers, regulators, investors, and delivery organisations. It enables (1) strategy credibility checks by linking national ambition to preconditions for investability, (2) identification of binding constraints and interdependencies that drive stop-start execution risk, and (3) clearer sequencing of policy interventions and risk-sharing needed to reach the final investment decision and deliver operating capacity. By making explicit the minimum institutional, industrial, and financing conditions required for progress, the roadmap supports more credible integration of iPWR SMRs into national decarbonisation and energy security pathways. • Develops a diagnostic roadmap for integral PWR SMR deployment. • Validates roadmap structure and interdependencies through iterative expert review (Delphi). • Links country readiness, technology readiness, and project delivery into an integrated decision-support framework. • Identifies coupled licensing–financing constraints as a major barrier to investment readiness and delivery.