Title: Matching Analysis of Technical Parameters and Safety Standards for Nuclear Replacement of Coal-Fired Units
Authors: Dongwang Zhang, Tuo Zhou, Zhihong Liu, Hairui Yang, Rushan Bie & Man Zhang
Institutions: Tsinghua University and Harbin Institute of Technology (China)
Published in: Energies, Vol. 17, Issue 22, Article 5583 (November 2024)
Overview
This 2024 review by researchers from Tsinghua University and the Harbin Institute of Technology examines in detail whether nuclear reactors could directly replace the boilers in existing coal power plants — a concept central to the emerging “coal-to-nuclear” (C2N) pathway.
The authors compare technical parameters, thermal cycles, and safety standards of both systems, using examples of two typical nuclear technologies:
- Pressurized Water Reactor (PWR, NHR200-II model)
- High-Temperature Gas-Cooled Reactor (HTGR, HTR-PM model)
Key Findings
- Thermal mismatch: Coal plants use higher-pressure, higher-temperature steam cycles (up to 605 °C and 25–30 MPa) compared with nuclear reactors (typically 280–310 °C and 6–8 MPa). This difference makes direct replacement technically complex without major redesigns.
- Operational differences: Coal units respond quickly to grid demand, while nuclear reactors have slower start–stop dynamics, making flexibility integration a challenge.
- Equipment differences: Nuclear turbines operate with wet steam and require special dehumidification measures and larger final-stage blades — increasing both size and cost.
- Safety frameworks: Nuclear plants follow strict, multi-layered safety regimes (IAEA SSR-2/1, SSG-2, RCC codes, etc.), far beyond the scope of conventional coal plant standards.
- Feasibility conclusion: The paper concludes that direct nuclear substitution for coal boilers is not currently feasible, due to disparities in technical parameters, construction time, and incompatible safety requirements.
Why it matters
While the authors caution that full “nuclear-for-coal” substitution remains unrealistic under current conditions, their analysis helps clarify what must change — technically and regulatorily — for future hybrid or repowering solutions.
By systematically mapping these gaps, the study provides a reference for policymakers and engineers exploring the potential evolution of C2N projects in China and beyond.
Repower Perspective
At Repower, we highlight studies like this because they help turn ambition into engineering.
Every detailed comparison, model, and pilot project brings us closer to a world where the massive infrastructure built for coal can be repurposed — not wasted — in service of a clean, resilient energy system.
The message is simple: it can be done — and research like this tells us how.