How to implement nuclear energy for data centers

How could data centers use nuclear energy?

According to Chris Sharp, CTO at Digital Realty, a normal data center uses around 32 megawatts of power, while an AI data center uses 80 MW. This will likely become the norm with AI's rapid growth.

A renewable power source is necessary to support this amount of consumption. Nuclear fission and fusion can generate massive amounts of energy with a low carbon footprint. Nuclear reactors also run 24/7 unlike energy production that relies on the weather, like wind and solar.

According to the U.S. Department of Energy (DOE), nuclear power has been used for more than 60 years to support energy grids and national defense activities. But that hasn't been true for powering data centers. This is because nuclear reactors are large-scale projects with strict regulations. These restrictions make it difficult to stand up nuclear reactors near data centers at scale. However, the invention of SMRs might make this possible.

Use of small modular reactors

SMRs have potential for the future use of nuclear energy within data centers. These reactors are smaller, more compact versions of typical nuclear reactors. SMRs, however, produce about a fifth of the amount of energy, according to National Grid. Advantages of SMRs include their compact nature, which makes them easy and cheap to manufacture and transport.

SMRs typically fuel submarines and aircraft carriers, providing them with enough power for up to 20 years without interruptions. If SMRs like these can be safely produced at scale, they could provide dedicated, stable and renewable power sources for data centers with few maintenance requirements.

According to DOE, efforts to support the development of SMRs are under licensing review by the Nuclear Regulatory Commission (NRC) and will likely deploy in the late 2020s to early 2030s. To reach that goal, technological developments, licensing and regulatory risks need to be addressed. Experimental efforts are undergoing testing now and, if successful, could accelerate the availability of SMRs in domestic and international markets. SMRs could be available to integrate on-site at data centers within a decade.

Benefits of nuclear power in a data center

Has low carbon emissions

According to Our World in Data, coal produces 970 tons of greenhouse gas emissions, which is 160 times more than nuclear energy per gigawatt-hour of electricity. Oil produces 714 tons of emissions more than nuclear energy, while natural gas produces 434 tons more than nuclear. On average, solar and wind energy also produce 47 tons and 5 tons more than nuclear, respectively. Use of nuclear energy could globally accelerate the decarbonization of data centers.

Has a minimal carbon footprint

Nuclear facilities use significantly less land than other energy alternatives, and SMRs use even less. While some carbon may be produced in the manufacturing of nuclear reactors, the overall carbon footprint is still the lowest overall compared to other sources of electricity.

Generates clean, pollution-free energy

Energy production and use are human-made sources of air pollutant emissions. These pollutants include particulate matter, sulfur oxides and nitrogen oxides, which enter the atmosphere and worsen air quality. Nuclear energy emits no air pollutants, which means data centers could help keep the air clean and free of harmful pollutants.

Provides dense, stable and reliable power

Nuclear energy has a high energy capacity, which is the amount of electricity a generator produces at maximum power. It also has a high energy density, so nuclear reactors produce a large amount of energy with little fuel. Reactors also do not rely on the weather to function properly. These high levels of capacity, efficiency and consistency result in stable, reliable power, which is what data centers need to ensure maximum uptime.

Challenges of nuclear power in a data center

Has low availability

The current availability of nuclear reactors is slim. This is partly due to the capital investment required to build nuclear plants, lengthy development times, poor public reception around nuclear safety and strict regulatory oversight. Restrictions should lower for data centers as advancements in nuclear technology continue.

Is difficult to dispose of or recycle waste

Though nuclear reactors don't generate much waste, the used fuel is dangerous to maintain and difficult to dump. Tools to recycle and reuse nuclear energy are still in their development and testing phase. Although SMRs require much less maintenance and specialty expertise to operate compared to large facilities, the infrastructure is not available for data centers.

Has an expensive upfront cost

Funding the construction of a nuclear facility is no small task, which is why only the largest data centers are considering nuclear energy. Aside from building costs, operating costs are high due to the strict protocols and high-level expertise necessary to operate nuclear reactors.

Is bound by a strict regulatory environment

Security and safety are paramount, so clear and stringent standards are required to use nuclear energy. Data centers must adhere to these policies and procedures. Government bodies are working together, both nationally and internationally, to establish regulations.

Current state of nuclear power in data centers

Powering data centers with nuclear energy is still largely in the R&D phase. However, tech giants, like Amazon, Google and Microsoft, are beginning to explore it.

In 2024, Amazon purchased a data center campus powered by a nuclear power plant from Talen Energy. This agreement supplements its carbon-free energy efforts to power AWS data centers around the world.

Public Service Enterprise Group is exploring the potential of direct power sales to data centers from its nuclear plants, Vistra is in talks with data center operators and Constellation might build advanced reactors at existing plants for data center energy supply. Google has also signed a deal to work with Nucor Corporation to help bring advanced nuclear projects online.

Microsoft has new job positions related to developing actionable strategies in the advanced nuclear energy space. Microsoft is searching for people to initiate plans for SMRs to power their data centers.

In addition, DOE has invested more than $600 million since 2014 to support the design, licensing and siting of NuScale's SMR design, its manufacturing plant and other domestic SMR concepts. NRC certified NuScale's SMR design in 2023, and the first module is expected to be operational by 2029.

What's needed to ensure safety

Past nuclear reactor meltdowns, such as Chernobyl, Fukushima and Three Mile Island, have left people with negative impressions on nuclear energy. Modern designs for advanced nuclear technology are safer in comparison.

The development of the International Atomic Energy Agency (IAEA) Safety Standards coincide with international consensus by world leaders in nuclear safety. The standards address all aspects of safety in the operation of nuclear power plants and regulatory activities.

The newest generation of reactors have incrementally improved from previous generations, with the goal to protect against everything from meltdowns and accidents to human error. SMRs are being intensively researched and are generally deemed safe. SMRs rely on passive systems to shut down automatically in the case of an incident or equipment failure. All reactor designs must go through extensive reviews, approvals and testing before they are certified for licensing.

SMRs require little intervention by data center operators. However, equipment maintenance and the disposal of nuclear waste are necessary and must be handled by certified professionals. Adhering to the strict regulations and safety protocols might prove to be difficult, but it is necessary for safety and security.

Nuclear energy holds potential as a clean, renewable source of energy for data centers. However, it is not feasible on a widespread level yet. According to IAEA, scientists can replicate many of the conditions needed for nuclear fusion routinely for experiments; however, we are lacking the confinement properties needed to scale this process up for energy production. While not viable currently, scientists and engineers are hard at work to make widespread nuclear fusion reactors a reality.

Jacob Roundy is a freelance writer and editor, specializing in a variety of technology topics, including data centers and sustainability.