As countries race to reach net-zero emissions and stave off climate change, nuclear energy is poised to play a vital role in decarbonising electricity and hard-to-abate sectors. With immense scalable capacity, always-on reliability, and ultra-low lifecycle emissions, advanced nuclear reactors can complement renewables expansion and provide clean heat, hydrogen, and industrial process energy. But to unlock nuclear’s full potential, governments must enact supportive policies and invest in next-generation technologies that enhance economics, flexibility, safety, and waste management. Read on to learn why nuclear is essential for full-scale decarbonisation and how innovative developments can overcome lingering challenges around costs, waste, and public perception.
—
The world is at a decisive moment in the fight against climate change. With greenhouse gas (GHG) emissions continuing to rise and average temperatures increasing, achieving net zero emissions by mid-century has become an urgent priority to avoid catastrophic climate impacts. To achieve net zero and limit future warming to 1.5C above pre-industrial levels in line with the Paris Agreement, nothing less than a complete transformation of the global energy system is required. This will necessitate rapidly phasing out fossil fuel use across electricity production, transportation, buildings, industry, and agriculture while simoultaneously scaling up all available low- and zero-carbon energy sources.
While renewable energy from solar, wind, hydropower, and biomass will shoulder much of the burden, there is growing recognition that nuclear power also has a vital role to play. Nuclear Energy offers a proven, always-on source of carbon-free electricity that can balance the variable output from renewables. It can also help decarbonise hard-to-abate sectors like heavy industry and shipping. Calls are mounting for greater policy support and investment to enable nuclear to make a larger contribution to deep decarbonisation efforts worldwide. However, challenges around costs, nuclear waste management, and public perception must also be overcome.
The Scale of the Net-Zero Challenge
Under the Paris Agreement, over 190 countries have committed to limiting global warming to well below 2C, preferably 1.5C, compared to pre-industrial levels. However, the world has already warmed about 1.1C, according to NASA. To have a 50% chance of hitting the 1.5C target, the Intergovernmental Panel on Climate Change (IPCC) estimates net-zero CO2 emissions must be reached globally around 2050, requiring deep cuts to GHG emissions of about 45% by 2030. This necessitates radically transforming the world’s 80% fossil fuel-powered energy system within a few decades.
Change in global surface temperature compared to the long-term average from 1951 to 1980. The year 2020 statistically tied with 2016 for the hottest year on record since record keeping began in 1880. Image: NASA.
While daunting, success is still possible if governments, businesses, and societies urgently adopt ambitious climate policies, invest in clean technology deployment at a mass scale, and make widespread behavioural changes enabling low-carbon living. The International Energy Agency (IEA) outlines a technically feasible route in its Net Zero Emissions by 2050 Scenario but warns this narrow path demands an “unprecedented transformation” of how energy is produced, transported, and used globally.
The Vital Role of Renewable Energy
Renewable energy sources such as onshore and offshore wind, utility-scale and distributed solar, hydropower, geothermal, tidal, and sustainable bioenergy have grown exponentially over the past decade and will undoubtedly deliver the bulk of future emissions reductions. According to the IEA’s Net Zero report, renewables are projected to supply around 90% of global electricity by 2050, up from 29% in 2020, through massive deployment of solar, wind, hydropower, and other technologies enabled by batteries for short-term storage.
Read more on the topic: Renewables on Track to Become Largest Source of Global Electricity by 2025, IEA Says
Electrification powered by renewables will play a central role across end-use sectors. For example, electric vehicles (EVs) are expected to make up almost 60% of all car sales globally by 2030 according to BloombergNEF. Heat pumps will replace fossil fuel furnaces and boilers in buildings. Industrial processes will shift toward using electricity instead of coal, gas, or oil. The plunging costs of renewables make this transition economically attractive. According to the International Renewable Energy Agency (IRENA), since 2010, the global weighted average levelised cost of electricity has fallen by 68% for utility-scale solar PV, 47% for onshore wind, 39% for offshore wind, and 29% for concentrated solar power.
However, despite their tremendous promise and competitiveness, renewables alone cannot achieve full decarbonisation. Challenges around intermittency, energy storage, transmission, and seasonal variability will constrain how fast renewable penetration can be ramped up. Difficult-to-electrify sectors like heavy industry, heavy transportation, and shipping will also rely on other low-carbon fuels. This is where advanced nuclear power steps in as a critical complementary technology.
Why Nuclear Energy is Essential to Reaching Net Zero
Nuclear energy has several unique attributes that make it exceptionally well-suited to be part of a net-zero emissions solution:
1. Scalable low-carbon generation capacity
Electricity output by region from nuclear power plants between 1970-2021. Image: World Nuclear Association.
Nuclear provides vast amounts of always-on, low-carbon electricity unconstrained by time of day or weather. In 2020, the world had 443 operable reactors with a combined capacity of 394 gigawatts (GW), supplying around 10% of global electricity, according to the World Nuclear Association. Nuclear plants are also not insignificantly sized. The typical reactor has a 1GW-capacity, so adding even a few plants can make a sizeable emissions impact. For example, if nuclear displaced a typical 500-megawatt (MW) coal plant running 80% of the time, around 3 million tonnes of CO2 could be avoided annually.
2. System stability
Nuclear is a dispatchable source that can flexibly ramp up and down to complement variable solar and wind generation output. This helps stabilise the grid and avoid blackouts. Areas with both nuclear and renewables as part of their electricity mix have been able to integrate shares of wind and solar and much higher without reliability issues compared to those without nuclear. France generates over 71% of its electricity from nuclear and 10% from hydropower and the remaining 20% from other energy sources.
3. Low-carbon heat for industry
Decarbonising the industry is incredibly challenging due to high process temperatures. Nuclear can generate high-temperature process heat for energy-intensive sectors like steel, cement, and petrochemicals that would otherwise rely on fossil fuels. Nuclear power has a minimal carbon footprint of around 15-50 grams of CO2 per kilowatt hour (gCO2/KWh). In comparison, the average footprint of a gas-powered generator is around 450 gCO2/KWh while for coal, it is around 1,050 gCO2/KWh.
4. Clean hydrogen production
Nuclear power can be used to produce hydrogen through low-carbon electrolysis, avoiding emissions from natural gas reforming. The IPCC estimates 3,000-8,000 gigawatts (GW) of clean hydrogen production capacity will be needed by 2050, with nuclear and renewables as likely energy sources.
5. Compact land footprint
Nuclear has the highest power density of any low-carbon technology, producing an enormous amount of electricity from a minimal footprint. An analysis by the Breakthrough Institute found that a typical 1 GW nuclear facility needs less than 1.5 square miles, compared with over 70 square miles for solar and over 260 square miles for onshore wind, generating equivalent annual output. Nuclear is ideal for countries with high energy demand but limited available land.
6. Proven reliability and safety
All nuclear reactors in the worlds combined have compiled over 18,000 years of operational experience and have undergone extraordinary safety and risk management advances. Generations III and III+ reactor designs now being built have enhanced passive safety features. Nuclear accidents remain extremely rare, especially relative to continued fossil fuel harm. The Chornobyl disaster, one of the world’s most renowned nuclear disasters, resulted from a severely flawed Soviet-era reactor design operated unsafely.
Overcoming the Challenges of Nuclear Energy
While the technology has compelling strengths, there are legitimate concerns often raised regarding nuclear power that must be addressed.
1. High upfront capital costs
Building new nuclear plants requires a greater upfront capital investment compared to wind, solar, or gas. However, the levelised cost of electricity from new nuclear is cost-competitive with other dispatchable low-carbon alternatives when factors like system value are considered. Small module reactors under 300 MW now entering commercialisation can also significantly cut nuclear costs through cheaper factory construction techniques.
2. Waste management
The issue of radioactive spent fuel and nuclear waste is often an obstacle to social acceptance. But new reprocessing and recycling technologies can dramatically reduce waste volumes and recover more energy. Several countries now also successfully implement deep geologic repositories for safe long-term waste isolation. Stakeholder engagement on repository siting and robust safety regulations are paramount.
Read more on the topic here: The Nuclear Waste Disposal Dilemma
3. Proliferation risk
Nuclear proliferation risks can be addressed through stringent safeguards and oversight applied by the International Atomic Energy Agency (IAEA) and strict enforcement of treaties like the Nuclear Non-Proliferation Treaty, …. Most nations today constructing new reactors are already nuclear powers. Furthermore, Generation IV fast neutron reactor designs are inherently proliferation resistant and can burn down stocks of spent fuel. Small modular reactors with built-in safeguards also pose less risk.
4. Public opposition
A legacy of accidents and lack of transparency continue to make nuclear controversial in some regions, especially in Europe. However, public opinion globally has been shifting positively as climate benefits become more apparent. Younger generations are notably more receptive. Clear communication, early engagement with critics, and community benefit programmes can further improve acceptance.
Key Policies to Enable Nuclear Growth
For nuclear to contribute more to net-zero goals, governments must enact supportive policies recognising its attributes as a low-carbon baseload source. These include:
- Carbon pricing: Placing a fee on CO2 emissions makes dispatch from low-carbon nuclear more economically competitive and encourages new plant construction.
- Clean energy standards: Standards requiring a share of electricity to come from low- or zero-carbon sources reward nuclear generation.
- Financial incentives: Subsidised financing, power purchase agreements, tax credits, and other mechanisms that improve project economics.
- Fleet preservation: Keeping existing reactors open avoids capacity losses and prevents fossil replacing nuclear. Most US states now have zero-emission credit programmes to value nuclear.
- Advanced reactor R&D support: Public research, design licensing, demonstration projects, and commercial deployment incentives help drive progress on next-generation advances.
Many nations have already made expanding nuclear energy part of their net zero plans, recognising its importance. For example, the UK aims to reach 24 GW of nuclear capacity by 2050 under its Ten Point Plan, France intends to build 6-8 new EPR reactors, and India has set a target of 63 GW by 2032. However, global nuclear capacity additions will need to accelerate significantly to reach IPCC projections of +59 to +106% by 2050 illustrated in their mitigation report. Solid policies and closer multinational cooperation on new plant construction, fuel services, waste management, and innovative reactor deployment will be essential to achieve this scale-up.
The Evolving Nuclear Technology Landscape
Advanced nuclear technologies now in development also promise significant improvements in economics, flexibility, safety, and waste profiles:
- Small modular reactors (SMRs): Producing under 300 MW, SMRs use modular factory construction to slash costs and can scale to meet demand. Examples include NuScale’s 77 MW LWR design and GE-Hitachi’s 300 MW BWRX-300.
- High-temperature reactors: Cooled by gas or molten salt, high-temperature reactors reach 700 – 900°C, enabling efficient industrial heat applications. China’s 250 MW Shidao Bay HTR is due online shortly.
- Fast neutron reactors: Fast systems can extract up to 100x more energy from uranium. Russia’s commercial BN-800 FNR already operates. China, India, and France also have demonstration FNRs.
- Molten salt reactors: MSRs use molten fluoride salts rather than water as the coolant, bringing major advantages like high operating temperatures, lower pressures, walk-away passive safety, and easier siting.
- Microreactors: Very small units under 10 MW suitable for remote communities and off-grid industrial sites. Examples include U.S. companies Westinghouse, UltraSafe and Oklo.
- Fusion: No nuclear fission; nuclear fusion combines isotopes of hydrogen to generate enormous heat. Massive public and private investment now aims to demonstrate fusion electricity commercially by 2035-2040.
Now Is the Time
Nuclear energy is poised and ready to contribute substantially to the global effort to reach net-zero emissions. Nuclear offers scalable, always-on low-carbon power to complement renewables expansion. It can decarbonise difficult sectors and provide clean hydrogen.
Newer technologies offer significant safety, cost, and waste improvements. However, to fully leverage its potential, governments must enact policies that appropriately value nuclear’s reliability and systemic attributes and create frameworks that enable faster innovation and deployment. With the unprecedented growth of all low-carbon technologies required in coming decades, now is the time to pursue a diverse, inclusive strategy that taps nuclear’s immense capabilities alongside renewables, carbon capture, energy efficiency, and other solutions. Successfully transitioning to an equitable and resilient net-zero economy will depend on empowering nuclear energy to play an expanded role worldwide.
Featured image: Lukáš Lehotský on Unsplash
