Nuclear power plants have long been recognized as a dependable source of low-carbon electricity, generating vast amounts of energy without emitting carbon dioxide during operation. In recent years, their potential role has expanded beyond electricity generation to support carbon capture and storage (CCS) initiatives. These technologies aim to reduce greenhouse gas emissions from industrial processes and power generation, helping countries meet their climate targets under the Paris Agreement. As the urgency of climate action grows, integrating nuclear power with CCS offers a pathway to deep decarbonization of sectors that are otherwise difficult to clean up, such as cement, steel, and chemical manufacturing.

Understanding Carbon Capture and Storage (CCS)

Carbon capture and storage is a suite of technologies designed to prevent CO₂ emissions from entering the atmosphere. The process typically involves three steps: capturing CO₂ from large point sources (like power plants or industrial facilities), transporting it via pipelines or ships, and storing it permanently in underground geological formations such as depleted oil and gas reservoirs or saline aquifers.

Capture Methods

There are three main capture approaches:

  • Post-combustion capture: CO₂ is separated from flue gas after burning a fuel. This method can be retrofitted to existing plants and is the most mature.
  • Pre-combustion capture: Fuel is converted into synthesis gas (hydrogen and CO), then the CO is shifted to CO₂ and hydrogen. The CO₂ is captured before combustion, leaving hydrogen to burn.
  • Oxy-fuel combustion: Fuel is burned in pure oxygen instead of air, producing a flue gas that is mostly CO₂ and water vapor, which can be easily separated.

Each method requires significant energy input for compression, solvent regeneration, or air separation. This energy penalty — typically 20–30% of the plant’s output — poses a challenge for CCS deployment. A reliable, low-carbon source of power and heat can offset this penalty, making nuclear reactors an ideal partner.

The Role of Nuclear Reactors in Supporting CCS

Nuclear reactors can support CCS in multiple ways, leveraging their unique characteristics: constant output, high-temperature heat capability, and low operating emissions. These functions go beyond simply powering capture equipment.

Providing Reliable Low-Carbon Power for CCS Operations

CCS systems require substantial amounts of electricity to run compressors, pumps, fans, and solvent regeneration units. For example, a typical post-combustion capture system on a coal plant consumes between 200 and 300 kWh per tonne of CO₂ captured. If the electricity used comes from fossil fuels, it undermines the net emissions reduction. Nuclear power offers a baseload supply that is carbon-free, ensuring that the energy penalty does not lead to additional emissions. Unlike wind or solar, nuclear plants can run at high capacity factors (over 90%) regardless of weather, providing the constant power needed for 24/7 CCS operations. This stability is critical for industrial facilities that cannot tolerate intermittent power supply.

Hydrogen Production via Nuclear Energy

Nuclear reactors can also produce hydrogen, which plays a dual role in CCS. First, hydrogen can be used as a clean fuel, replacing fossil fuels in hard-to-abate sectors. Second, hydrogen is a key input for some CCS processes. For example, the production of ammonia (used as a hydrogen carrier or fertilizer) can generate a pure CO₂ stream that is easy to capture. Additionally, hydrogen can be used for direct reduction of iron in steelmaking, eliminating CO₂ emissions from traditional blast furnaces.

The most promising pathway is high-temperature steam electrolysis (HTSE), which uses heat and electricity from nuclear reactors to split water into hydrogen and oxygen. Since nuclear reactors can supply heat at temperatures of 700–950°C (depending on the reactor type), the efficiency of electrolysis can exceed 80%, compared to around 60% for low-temperature electrolysis. This makes nuclear-powered hydrogen production cost-competitive with hydrogen from natural gas with CCS. Several countries, including the United States and France, are actively researching and demonstrating nuclear hydrogen production.

Process Heat Supply for Industrial CCS

Many industrial CCS pathways require high-temperature heat for chemical reactions. For instance:

  • Calcium looping: This capture process uses calcium oxide to absorb CO₂, then regenerates the sorbent by heating it to over 900°C. Nuclear reactors can supply this heat without generating additional CO₂.
  • Direct air capture (DAC): Some DAC technologies require temperatures of 800–900°C to release captured CO₂ from solid sorbents. Advanced nuclear reactors, particularly high-temperature gas-cooled reactors (HTGRs) and molten salt reactors (MSRs), can provide this heat efficiently.
  • Cement production: Cement clinker production is inherently carbon-intensive because the raw material (limestone) releases CO₂ when heated. Using nuclear process heat to calcine limestone could reduce emissions while still producing clinker.

By co-locating nuclear reactors with industrial facilities, the high-temperature heat can be delivered directly, avoiding the need for separate combustion of fossil fuels. This integration creates a synergy that can decarbonize sectors that are currently responsible for a large share of global CO₂ emissions.

Co-Location and Energy Hub Concepts

The concept of nuclear cogeneration — using a reactor to supply both electricity and heat — is gaining traction. For instance, a single large reactor could power a CCS-equipped coal or gas plant, produce hydrogen for nearby steel mills, and supply district heating to a city. Such energy hubs maximize the utilization of the nuclear asset and spread capital costs across multiple revenue streams. This approach is being explored in countries like Canada, China, and the United Kingdom, where integrated energy parks are being designed around small modular reactors (SMRs).

Advantages of Nuclear-CCS Integration

Combining nuclear power with CCS offers several compelling benefits that go beyond what either technology can achieve alone.

Deep Decarbonization of Hard-to-Abate Sectors

Even with aggressive deployment of renewables, some industrial processes will still require high-temperature heat or chemical feedstocks that cannot be fully electrified. Nuclear-CCS integration can address these residual emissions. For example, the production of ammonia, methanol, and steel can be made nearly carbon-neutral using nuclear hydrogen and process heat. This is especially important for sectors that contribute significantly to global emissions — cement alone accounts for about 8% of anthropogenic CO₂.

Energy Security and Grid Stability

Nuclear plants provide stable, dispatchable power that can compensate for the variability of wind and solar. When combined with CCS, the overall system becomes more resilient because the nuclear plant can continue to supply power even during periods of low renewable generation, while the CCS system ensures that any remaining emissions from industrial sources are captured. This baseload reliability is essential for maintaining grid stability in a deeply decarbonized system.

Economic Benefits and Job Creation

Integrating nuclear with CCS can create new industries and jobs. Building advanced reactors, developing hydrogen infrastructure, and retrofitting industrial plants with CCS will require skilled labor and engineering expertise. Furthermore, the captured CO₂ can be used for enhanced oil recovery (EOR) or as a feedstock for synthetic fuels, generating additional revenue. Countries that invest early in nuclear-CCS could become leaders in clean energy technology exports.

Challenges and Barriers

Despite its promise, several obstacles must be overcome before nuclear-CCS integration becomes widespread.

High Costs and Capital Intensity

Nuclear power plants have high upfront capital costs, and CCS adds another layer of expense. Currently, the cost of CCS ranges from $50 to $150 per tonne of CO₂ captured, depending on the source and capture method. When combined with the cost of nuclear energy (typically $60–$100 per MWh), the overall system may be more expensive than alternatives like renewables with battery storage. However, cost reductions are expected as advanced reactors and CCS technologies mature, and as carbon pricing or incentives reduce the gap.

Regulatory and Licensing Hurdles

Integrating nuclear with CCS involves novel regulatory frameworks. Nuclear regulators must approve the co-location of reactors with industrial facilities, while CCS regulators must ensure safe geological storage. Overlapping jurisdictions can delay projects. Additionally, many countries lack specific regulations for nuclear cogeneration or for the use of nuclear heat in chemical processes. Streamlining these processes is essential.

Public Acceptance and Siting

Nuclear power and CCS each face public skepticism. Concerns about nuclear accidents, radioactive waste disposal, and the long-term safety of CO₂ storage must be addressed through transparent communication and robust safety demonstrations. Co-locating nuclear and CCS may also raise concerns about industrial hazards. Community engagement and benefit-sharing can help build trust.

Water Use and Environmental Footprint

Nuclear reactors, especially those using once-through cooling, consume significant amounts of water. CCS processes also require water for solvent scrubbing and cooling. In water-stressed regions, this combination could be problematic. Advanced cooling technologies (such as dry cooling) or the use of treated wastewater could mitigate this issue, but at additional cost.

Current Projects and Case Studies

While large-scale nuclear-CCS integration is not yet commercial, several initiatives are exploring the concept.

The Prairie Island Integration Study (USA)

The Prairie Island nuclear plant in Minnesota has been the subject of a feasibility study to use its waste heat for direct air capture. The plant’s 1,100 MW of capacity could provide the heat and electricity needed to operate a DAC facility capturing about 1 million tonnes of CO₂ per year. The study concluded that the concept is technically feasible, though economic viability depends on carbon prices and hydrogen markets.

The UK’s HALEU and Industrial CCS Plans

The United Kingdom is pursuing high-assay low-enriched uranium (HALEU) fuels for advanced reactors, and the government has designated several CCS clusters (e.g., HyNet and Net Zero Teesside). These clusters plan to use gas-fired CCS for hydrogen production, but studies are underway to integrate nuclear cogeneration. The UK’s Advanced Modular Reactor programme includes designs that could supply process heat for industrial users, potentially coupled with CCS.

China’s HTR-10 and Hydrogen Cogeneration

China’s HTR-10, a 10 MW high-temperature gas-cooled test reactor, has demonstrated cogeneration of electricity and process heat. It has been used to produce hydrogen via HTSE, and researchers are exploring its application in coal-to-chemicals plants with CCS. China’s plan to scale up HTR-PM (a 200 MW demonstration) could provide a blueprint for nuclear-CCS integration in industrial clusters.

International Research and Collaboration

The International Atomic Energy Agency (IAEA) has published reports on the role of nuclear power in supporting CCS, highlighting opportunities for cogeneration and hydrogen production. The U.S. Department of Energy’s Advanced Reactor Demonstration Program (ARDP) also includes projects that could incorporate CCS. These efforts indicate growing recognition of the synergy between nuclear and CCS.

Future Outlook and Research Directions

The future of nuclear-CCS integration depends on technology development, policy support, and market conditions.

Advanced Reactors and Cost Reduction

Small modular reactors (SMRs) and microreactors could reduce capital costs and allow incremental deployment. These reactors can be factory-built and transported to sites, making them easier to co-locate with industrial facilities. Generation IV reactors, such as the molten salt reactor and the very-high-temperature reactor (VHTR), operate at even higher temperatures (up to 950°C), enabling more efficient hydrogen production and direct heat supply for CCS. Continued R&D is needed to bring these reactors to commercial readiness.

Policy and Carbon Pricing

Strong carbon pricing or equivalent regulations will be necessary to make nuclear-CCS competitive with fossil fuels. Incentives such as the U.S. 45Q tax credit for CCS (currently $85/tonne for storage) can help. Additionally, governments can support demonstration projects that prove the technical and economic viability of nuclear-CCS integration. Long-term contracts for zero-carbon electricity and hydrogen can de-risk investments.

Integration with Direct Air Capture

Direct air capture technologies, which remove CO₂ directly from the ambient air, require significant energy. Nuclear power could provide the needed heat and electricity, while also supplying the infrastructure for storing the captured CO₂. Several studies have shown that nuclear-driven DAC could achieve negative emissions at scale, a critical requirement for meeting net-zero targets.

Conclusion

Nuclear reactors have a significant role to play in supporting carbon capture and storage initiatives, extending their value beyond low-carbon electricity generation. By providing reliable power, high-temperature heat, and hydrogen production capabilities, nuclear can help overcome the energy penalty of CCS and enable deep decarbonization of industrial sectors. Challenges such as cost, regulation, and public acceptance remain, but ongoing research and demonstration projects are paving the way. As the world accelerates efforts to combat climate change, integrating nuclear power with CCS could become an essential tool for achieving net-zero emissions by mid-century.