Decarbonizing Heat: The Hidden Giant

Published September 29, 2025

Most discussions on net zero transition highlight electricity, renewable power, and grid decarbonization. However, in many heavy industries, the real challenge lies in heat. Industrial heat often makes up 60 to 80 percent of total energy use in sectors like cement, food processing, and textiles. Despite this, strategies to decarbonize heat lag far behind, creating a gap between corporate climate reporting and actual emissions abatement.

Industrial Heat: The Overlooked Carbon Challenge

Industrial heat accounts for roughly 10 percent of global carbon dioxide emissions. While electricity procurement gets visibility through renewable energy certificates and power purchase agreements, heat is more complex and is frequently buried in Scope 1 or Scope 3 emissions. Different temperature ranges present unique challenges:

Low temperature (below 150°C / 300°F): common in food and textile industries.
Medium to high temperature (500°C / 930°F and above): required in cement, glass, and steel production. The higher the temperature requirement, the more difficult it becomes to replace fossil fuels with clean alternatives.

Pathways to Decarbonizing Heat

Several solutions are emerging to tackle the thermal challenge:

Electrification: electric boilers and industrial heat pumps are well suited for low and medium temperature applications.
Hydrogen: being tested in steel and glass industries where high heat is essential.
Bioenergy: used in specific regions where sustainable biomass is available.
Carbon capture: necessary in processes that inherently release carbon beyond fuel combustion.
Digital optimization: process redesign, waste heat recovery, and smart energy management systems.

Case Examples from Industry

Some industries are already moving forward with decarbonized heat pilots. In the brewing sector, Heineken has been actively investing in the deployment of electric boilers across a number of its European facilities. These boilers, powered by renewable electricity, allow the company to cut natural gas use for steam production and demonstrate how a traditionally fossil fuel intensive process can be adapted. Beyond technical implementation, Heineken has also paired these projects with commitments to renewable energy procurement, ensuring that the switch to electrification is linked directly to low carbon sources.

In the steel industry, the HYBRIT initiative in Sweden represents a pioneering effort to replace coal based blast furnaces with hydrogen based direct reduction of iron. Backed by companies such as SSAB, LKAB, and Vattenfall, HYBRIT has already produced pilot quantities of fossil free steel, which have been used by partners in the automotive sector. The project illustrates both the technical complexity and the transformative potential of decarbonized industrial heat, requiring new infrastructure, supply chains for green hydrogen, and long term corporate investment strategies.

Closing the Reporting Abatement Gap

While companies report progress through renewable electricity procurement, heat strategies remain underdeveloped. For energy intensive businesses, ignoring heat can undermine long term climate goals. To close the gap, companies can:

Conduct comprehensive heat audits.
Apply internal carbon prices to thermal fuel use.
Launch pilot projects with electrification or hydrogen readiness.
Evaluate partnerships for waste heat utilization and efficiency upgrades. The benefits extend beyond carbon reduction, including improved efficiency, regulatory readiness, and stronger ESG performance.

Conclusion

Heat is the hidden giant in the path to net zero. Without confronting industrial thermal energy, corporate decarbonization plans risk being incomplete. Businesses should raise heat decarbonization to the same level of priority as electricity procurement in order to deliver real emissions reductions and secure long term competitiveness.