Understanding Industrial Process Heat and the Decarbonization Challenge

Introduction

Almost everything you touch in a day required heat before it reached you. The milk in your coffee, the paper in your notebook, the concrete under your feet, the glass in your window, and the steel in your car all depended on carefully controlled thermal energy during manufacturing. Yet that energy is largely invisible to the people who rely on it.

Industrial process heat is one of the largest uses of energy in manufacturing, and one of the most difficult to decarbonize. Each process needs heat with a particular temperature, pressure, flow, delivery method, and level of reliability. This article explains what industrial process heat is, why it is difficult to decarbonize, and how advanced nuclear energy and small modular reactors (SMRs) can provide reliable energy for industrial applications.

The Invisible Energy Behind Everyday Products

Industrial process heat is thermal energy used to manufacture, refine, separate, dry, melt, cure, sterilize, or chemically transform a product. The U.S. Department of Energy (DOE) describes it as thermal energy used to produce, treat, or alter manufactured goods.

Common examples include:

Pasteurizing food and beverages
Drying paper, lumber, and coatings
Heating and separating crude oil into fuels and other products
Melting or heat-treating metals and glass
Heating limestone to make cement

The scale is significant. In DOE’s latest comprehensive analysis, based on 2018 manufacturing data, process heating accounted for 51% of onsite energy use. DOE also estimates that about one-third of the energy consumed by process heating is ultimately lost as waste heat.

Process heat describes an end use, not a specific fuel or technology. It can be generated by combustion, electricity, nuclear energy, solar thermal energy, or recovered waste heat. That heat may be applied directly or delivered through steam, hot water, thermal oils, furnaces, kilns, dryers, or other systems. Electricity can also be converted directly into process heat through resistance heating, induction, microwaves, or electric arcs.

Temperature, Pressure, and Why the Specification Matters

An industrial heat requirement is not a single number. It is a detailed specification, and each part of that specification affects which technologies can do the job.

Temperature: The Grade of the Heat

Temperature describes how intense the heat must be. Heat at 120°C might work well for food processing or evaporation, but it cannot run a cement kiln or glass furnace. A low-temperature source cannot simply substitute for a high-temperature duty. Engineers sometimes refer to this difference as the heat grade.

Pressure and Steam Conditions

When steam carries the heat, pressure matters because it affects how steam moves through a facility and, for saturated steam, the temperature at which it condenses and releases energy. Industrial plants therefore specify both temperature and pressure rather than asking only for steam.

Saturated steam is at the boiling temperature that corresponds to its pressure. When it condenses on a cooler surface, it releases a large amount of energy at a predictable temperature. Superheated steam has been heated above that boiling temperature and is used when a process needs hotter or drier steam, or when steam will drive a turbine.

Flow, Purity, and Reliability

Temperature and pressure do not show how much energy a process receives. Engineers also consider mass flow, energy content, steam quality, purity, and availability. The heat must arrive in the right amount, under the right conditions, and on the schedule the process requires.

The Industrial Heat Ladder

One way to picture process heat is as a ladder, with temperature rising on each rung. The ranges below are illustrative. Real processes vary widely.

These temperature ranges matter because they help determine how an energy source can be integrated with an industrial facility. Depending on the process, an SMR may supply electricity, steam, or both, while additional equipment can raise the steam to the required temperature and pressure.

Why Industrial Heat Is Hard to Decarbonize

A motor or control system can often use electricity from a different generation source without changing the equipment itself. Replacing a boiler, furnace, kiln, dryer, or steam network may require significant changes to a facility’s equipment and infrastructure.

Heat requirements are application-specific. Usable heat must match the process temperature, pressure, delivery method, and flow.
Industrial plants require high reliability. An interruption can stop production, damage equipment, or affect product quality. Some processes operate continuously for long periods and have little tolerance for a variable heat supply.
Fossil-fuel equipment is deeply embedded. Boilers, burners, furnaces, pipelines, and site utilities are expensive assets designed for long service. Replacing them before the end of their useful life can be costly and disruptive.
Electrification can create new power-system needs. Replacing fossil-fuel equipment with electric boilers, furnaces, or other systems may require additional generation, grid capacity, substations, and site electrical infrastructure.
Some emissions come from manufacturing chemistry rather than the fuel used to produce heat. Cement production, for example, releases carbon dioxide when limestone breaks down, so replacing fossil-fuel heat does not eliminate every industrial emission.

Where Nuclear Energy and SMRs Fit

A nuclear reactor produces heat first. In a power plant, that heat is generally used to make steam and generate electricity. With appropriate isolation and heat-transfer equipment, a nuclear system can also provide thermal energy to an industrial steam network or produce steam and electricity together.

Potential attributes for industrial applications include:

Firm heat and power that are available regardless of weather
The ability to produce steam and electricity from the same energy source
Modular plant configurations that can be matched to different demand levels
Long refueling intervals and a compact on-site fuel inventory
Integration with hydrogen, chemical, refining, and water systems

For processes that require conditions above the reactor’s steam outlet, an SMR can provide electricity or steam while heat exchangers, heaters, or compressors raise the final temperature and pressure.

NuScale and Industrial Process Heat

NuScale has evaluated integrated energy system configurations designed to use NuScale Power Modules™ to supply steam and electricity and support hydrogen and ammonia production. This work includes system modeling, technical and economic analyses, and research into equipment that can match reactor-generated heat with industrial steam requirements.

Hydrogen and Ammonia Production

NuScale studies have examined how electricity and steam from NuScale Power Modules could be integrated with several hydrogen-production technologies. Hydrogen can also be used to produce ammonia, an important ingredient in fertilizer and other industrial products. These studies illustrate how an integrated NuScale-powered plant could generate electricity and produce hydrogen and ammonia.

The 2025 ORNL Techno-Economic Assessment

In 2025, Oak Ridge National Laboratory, in collaboration with NuScale, published a techno-economic assessment of an integrated energy system serving a large chemical facility. Using actual facility conditions and historical operating data, the analysis examined configurations involving NuScale Power Modules, existing boilers, grid electricity, and steam heat-augmentation equipment.

The reference facility required approximately:

1.34 million kilograms of process steam per hour
A steam temperature of about 400°C
A steam pressure of 600 psig, or about 4.1 MPa gauge
72.5 megawatts of electricity

The modeling found that several modular and hybrid configurations could meet these energy needs while supporting operating flexibility, economic performance, and carbon dioxide reductions of 80% to 90%.

The assessment also considered reliability and siting. Staggered refueling allows all but one module to remain online, while redundant configurations can help maintain service during a module outage.

More broadly, a NuScale-powered plant could operate in island mode to serve a dedicated industrial site. NuScale’s U.S. Nuclear Regulatory Commission (NRC)-approved methodology supports a site-boundary emergency planning zone. This allows process-heat users to locate closer to the plant, reducing the distance steam must travel.

The Ebara Elliott Energy Collaboration

In March 2026, NuScale and Ebara Elliott Energy announced a collaborative research program to demonstrate and field-test a commercial-scale, high-temperature steam compressor. The program builds on earlier NuScale research into producing industrial process steam at commercial temperatures, pressures, and flow rates.

Under the proposed configuration, thermal energy from a NuScale Power Module would pass through an intermediate heat exchanger to produce an isolated secondary steam supply. A high-temperature compressor would then raise the steam to 500°C or higher for petrochemical and other high-temperature industrial applications.

Together, these efforts show how NuScale Power Modules can be paired with heat exchangers, compressors, electric heaters, steam networks, and controls to meet industrial requirements for temperature, pressure, flow, and reliability. Completed analyses provide a technical foundation for these applications, while ongoing equipment-development work is advancing methods for delivering higher-temperature process steam.

Conclusion: Reliable Energy for Industrial Processes

Industrial process heat is essential to manufacturing, but it is difficult to decarbonize because each application requires specific temperatures, pressures, flow rates, and levels of reliability.

SMRs can help meet those requirements by supplying firm electricity and steam, while heat exchangers, heaters, and compressors adapt that energy for particular industrial processes. NuScale’s completed studies and ongoing equipment-development work show how NuScale Power Modules can support industrial-scale steam requirements as well as hydrogen and ammonia production.

This work demonstrates how NuScale SMRs can extend reliable, low-carbon nuclear energy beyond electricity generation and provide a practical pathway for industrial decarbonization.