Clean Heat: Harnessing Heat from Nuclear to Fuel Heavy Industry

At Last Energy, we often reference the “power” of nuclear. As an energy source, nuclear has the power to sustain the needs of high energy users, produce clean hydrogen, and even fuel desalination. 

But the power of nuclear is twofold. In addition to producing clean, accessible electricity, nuclear also produces heat: a natural byproduct with far-reaching applications.  

Today, we’re focusing on the second superpower of nuclear, in addition to clean electricity: its capacity to produce heat without carbon, and at a scale that could fuel the demands of heavy industry, where heat drives hundreds of essential functions.

Many nuclear power plants produce heat through fission, including the PWR-20 by Last Energy. Fission has been used for decades to generate electricity by splitting uranium atoms apart, and heat from fission can be used for various industrial processes: ranging from steam electrolysis to melting iron.  

Of course, other energy sources also produce heat. So, what makes nuclear energy special?

Clean Process Heat: Nuclear’s Second Superpower

Compared to other energy sources, nuclear is the only credible zero-carbon option for major industrial heat applications, per the World Nuclear Association (WNA). 

Renewable energy sources are powerful, and we still need them. But when night falls, when the stability of the electric grid fluctuates, and as global demand for industrial products continues to rise, we need nuclear energy to generate enough process heat. 

Process heat is thermal energy used directly in the preparation or treatment of materials to produce manufactured goods. In heavy industry, this heat may be used for drying, refining, warming, cooling, manufacturing, and other industrial processes.  

Process heating equipment depends on high temperatures, ranging from 300°F to as high as 3000°F (129°C - 1649°C), which require large amounts of energy to generate. Globally, industrial process heat accounts for more than two-thirds of the total industrial energy consumption.   

Today, many processes in heavy industry rely on fossil fuel combustion – which is where nuclear energy enters the picture. As a carbon-free alternative, nuclear can scale to power industrial facilities and generate high-temperature, 100% clean heat at a constant rate, while reducing the economic and climatic costs of our reliance on fossil fuels. 

Heat for Heavy Industry – But at the Price of Carbon

Traditionally, energy sources that produce heat through combustion include fossil fuels like natural gas, coal, and oil. When fossil fuels are burned, they release large quantities of heat, which is used to make electricity for heavy industry and other energy-intensive sectors.  

In 2022, global carbon dioxide emissions from energy combustion and industrial processes grew by 0.9%, reaching a new all-time high of 36.8 Gigatonnes. Current global climate policies will reduce carbon emissions, but not enough to reach international “net-zero” targets.  

To achieve global net-zero emissions by 2050, renewable heat consumption would have to advance 2.4 times more quickly, coupled with rapid and widespread changes in behavior and insulation technology in both commercial buildings and heavy industry, according to the International Energy Association (IEA).

Some Renewables Generate Heat – But Only Intermittently

As an alternative to fossil fuels, some industrial customers turn to renewable sources for their thermal energy needs. Of the non-fossil energy sources, only solar, geothermal, biomass, landfill gas, sewage treatment plant gas, and biogases become available in the form of heat or are usually converted into heat.  

Solar, biomass, and geothermal – the three main forms of renewable energy sources for heat – are conceivably “better” for the environment, as they emit less carbon than fossil fuels. However, renewables are intermittent, meaning their ability to produce heat depends on the time of day, local climate, and weather conditions. 

As a result, “100% renewable” corporations do not actually cover all their energy use with renewables; nor can they generate enough heat from renewables to sustain their operations 24/7.  

Other Challenges Posed by Renewables

In renewable heat generation, energy inefficiency complements the challenge of intermittency. Even among renewables that generate heat, some of this thermal energy is never utilized.  

While advancements in thermal insulation could improve energy efficiency, reduce costs, and shrink customers’ overall carbon footprint, renewable heat developments are insufficient to contain fossil fuel-based heat consumption, based on a 2022 report from the IEA.  

Even with high-quality insulation, not all renewable sources are equally fit to provide thermal energy, and many pose specific geographic and temporal requirements.

To obtain heat from geothermal power plants, for example, energy suppliers must locate the plants next to tectonic plate boundaries. For energy purchases driven by solar power, customers must purchase power from the grid during the nighttime, when the sun isn’t shining; and, in many cases, the grid still runs on fossil fuels. 

And while biomass releases heat when burned, it is not necessarily carbon-neutral. Biomass is primarily sourced from woody biomass and gas or liquid biofuels, and the extraction and burning of these substances could have detrimental effects on air quality, soil health, and biodiversity.

While these considerations do not negate the value of renewable resources, they illuminate the potential role of nuclear in a hybrid energy system in both heavy industry and elsewhere.

Industrial Heat from Last Energy

By flexibly adjusting their heat output, nuclear plants can complement and ultimately enhance the efficiency of renewables. Nuclear technology is already equipped to meet our industrial needs. By design, nuclear power plants convert one third of the heat produced into electricity: specifically through the steam-generating process of fission, which spins a turbine to create electricity. This heat can be used to decarbonize natural gas and coal heat processes.  

At Last Energy, the PWR-20 design and near-universal siting allows industrial customers to harness this thermal energy and generate sufficient process heat. For customers seeking to align carbon-zero goals with industrial demands in multiple locations, Last Energy can scale the PWR-20 to meet the needs of industrial customers wherever they need heat.

Heat Now & Hydrogen in the Future

In addition to process heat, what would otherwise be wasted heat from nuclear plants can also be used for desalination, heating buildings – also called district heating – and even the production of hydrogen. 

As we progress toward goals for net-zero carbon emissions, the hydrogen proposition is especially exciting. Hydrogen is an abundant, clean, and versatile fuel that yields water instead of carbon dioxide when burned.

According to the WNA, nuclear energy can be used to make hydrogen through electrolysis, and hydrogen could serve as an industrial-scale replacement for coke in steelmaking and other metallurgical processes. In the future, hydrogen could provide long-term energy storage, fuel for heavy-duty transportation, and decarbonize a range of heavy industries such as steel manufacturing and transportation. 

Using power from nuclear power plants, energy users could potentially create hydrogen, transport it to an industrial plant, and then burn the hydrogen to generate power: a vision shared by Last Energy in the UK, at the 2023 Decarb Connect conference in London. 

Relative to fossil fuels, burning hydrogen is a carbon-free ordeal. And compared to both fossil fuels and renewables, nuclear is a scalable, carbon-free source of heat. If we start the transition to nuclear now, we have an opportunity to transform both industrial processes and everyday energy needs.

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