Electrify industrial heat generation to eliminate emissions

Industry accounts for 25% of total CO₂ emissions from energy systems, with process heat making up nearly two-thirds of industrial energy demand. Today, more than 80% of this heat still comes from fossil fuels, making its decarbonization essential for achieving net-zero emissions. Fortunately, various renewable heating solutions, such as heat pumps, solar thermal, and thermal energy storage, are already commercially available

Despite its potential, electrification remains underutilized in industry. In 2022, only around 4% of industrial heat globally was electrified. However, this share is projected to nearly triple to 11% by 2028, according to the International Energy Agency.[1] The long-term potential is even greater as approximately 60% of industrial heat could be electrified using commercially available technologies today, with this figure expected to rise to 90% by 2035 as emerging technologies mature.[2] Importantly, all industrial heat demand below 500°C can already be met with mature electric solutions.[3]

Electrification solutions encompass a wide range of technologies that supply heat using electricity instead of burning fuel. They generate heat in industry through various principles, such as resistance heating (passing electric current through a conductor), induction heating (using fluctuating magnetic fields), electric arc heating (creating high-temperature arcs), or heat pumps (heat transfer via compression cycles). Depending on the technology employed, these solutions can cater to a wide range of applications, including those requiring temperatures above 1,800°C.

Figure 1: Simplified schema of a heat pump system

Electrification solutions for industrial heat can be roughly grouped into three main categories – electric boilers, heat pumps, and electric furnaces.

• Electric boilers use electricity to heat up water either by flowing it through the water (electrode boiler) or by heating up metal which then transfers the heat to the water (resistance boiler). They are drop-in replacements for fossil fuel boilers and are suitable for a wide range of industrial steam applications.

• Heat pumps transfer heat from a lower-temperature source (e.g. air, water, or waste heat) to a higher-temperature sink by circulating and compressing a working fluid using electricity. They are highly efficient because they move existing heat rather than generating it. This efficiency is measured by the Coefficient of Performance (COP), which indicates how many units of heat are delivered per unit of electricity consumed. In industrial applications, COPs typically range from 2 to 5, meaning 1 unit of electricity can provide 2 to 5 units of heat, and in certain applications can exceed 10. This category also includes Mechanical Vapor Recompression (MVR) systems, which recover and compress waste steam to a higher temperature and pressure, enabling its reuse in industrial processes.

• Electric furnaces usually heat up air or materials directly, making them more suitable for high-temperature applications. They include technologies such as resistive heating, plasma torches, shock-wave heating, or induction.

More use cases available in the WBCSD’s Renewable industrial heat navigator brief: Electrification solutions.

Sustainability impact

Climate

Carbon savings from electrification depend on the carbon intensity of electricity used. In extreme cases, such as regions still heavily reliant on coal, like parts of India, electrification can paradoxically result in higher overall emissions. The benefits can be therefore maximized through combination with power purchase agreements or on-site renewable power generation. However, typical emissions reduction is 200-400 kg CO2-eq per MWh of electrified heat.

Another consideration is the global warming potential (GWP) of the working fluid used in a heat pump. In the event of leakage, some working fluids can contribute significantly to greenhouse gas emissions. As a result, modern heat pumps use only low-GWP working fluids, such as ammonia or hydrocarbons, to minimize climate impact.

Nature

Electrification solutions have limited land footprint and can be installed into existing industrial sites, not needing additional land.

Social

Electrification eliminates local air pollution (NOx and other harmful emissions) associated with conventional combustion of fossil fuels.

Business impact

Benefits

Electrification solutions offer several advantages over conventional fossil fuel systems and even other renewable heat options, such as solar thermal:

• They have higher energy efficiency, especially in the case of heat pumps, which can deliver up to 10 times more heat than the electricity they consume.

• They can supply heat across a wide range of temperatures, from low-grade heating to high-temperature applications above 1,800°C, and can be scaled from a few kilowatts to tens of megawatts.

• They can be aggregated to provide flexibility services to the electricity grid, creating opportunities for additional revenues from demand-side management.

• They are versatile and precise, offering improved control over temperature levels and heat quality, improved worker safety, and often more efficient product processing.

• They have a limited land footprint compared to solar thermal, making them suitable for retrofitting into existing industrial sites.

• They reduce onsite air pollution, eliminating combustion-related emissions and supporting cleaner, quieter industrial operations.

Costs

The commercial viability of electrification is closely connected with the achieved energy efficiency:

Implementation

Typical business profile

Electrification solutions are currently best suited for companies in sectors such as food and beverage, pharmaceuticals, paper & pulp, or chemicals, which use low and medium temperature heat. Commercially available electrification technologies can already cover all of their heat demand.

However, electrification has the potential to decarbonize heat in almost all industries, even including chemicals, steel, and cement. For example, electric arc furnaces used for recycling of scrap metal already deliver heat with temperatures over 1800°C and are technologically mature. Therefore, specific applications, such as electric steam crackers or flat glass lines, are currently under development.

Approach

Electrification solutions are usually implemented as a capital investment project. However, they can be combined with Heat-as-a-Service.

Electrification solutions can be implemented to intentionally cover only parts of the heat demand. For example, when installing an electric boiler, the existing fossil fuel boiler can be retained. This allows companies to switch between systems based on current energy prices (e.g. run the electric boiler only during the day when electricity prices are low thanks to solar PV). This can be a practical first step toward electrification. Additionally, utilities and other energy companies offer flexible tariffs where they supply both the electricity and the fossil fuel based on which is cheaper.

Stakeholders involved

• Manufacturing plant director: Electrification solutions supply heat which is instrumental to the manufacturing processes. The implementation project therefore requires strong buy-in from the plant leadership.

• Operations: In addition to the plant leadership, company-level operations professionals should bring in specialized expertise and experience from similar projects.

• Finance: Electrification usually represents a large capital investment which in most companies requires approval of an investment committee including finance professionals.

• Sustainability: Electrification significantly reduces Scope 1 emissions and should be included in long-term emissions reduction plans.

Key parameters to consider

• Temperature lift of heat pumps: Temperature lift refers to the difference between the heat source temperature (e.g. waste heat) and the heat sink temperature (i.e. the required process temperature). The higher the temperature lift, the lower the system efficiency (COP) and the higher the capital expenditure (CapEx). For example, achieving very high lifts may require a multistage configuration, where multiple heat pumps are connected in series. Typical industrial applications involve temperature lifts ranging from 50°C to 100°C.

• Availability of waste heat for heat pumps: Heat pumps require a stable waste heat source. To ensure reliability, this source can be combined with thermal storage to deliver consistent heat when needed. Common industrial waste heat sources include exhaust gases, humid air from dryers, hot air from machine rooms, low-pressure steam, or condensate from cooling processes. The waste heat can originate from the same process it serves. For example, hot air from a dryer can be condensed and used to supply a heat pump that, in turn, heats the dryer itself.

• Grid access: For electric boilers, the required electrical connection capacity directly corresponds to the replaced fossil fuel capacity. Heat pumps require significantly less electrical capacity, as their rated thermal output (in MW) must be divided by their efficiency (COP) to determine the actual electrical demand.

Implementation and operations tips

Common implementation success factors reported by companies are:

• Availability of subsidies for innovative or energy efficient projects

• Aim to increase energy efficiency and reduce reliance on fossil fuels

• Successful cooperation among all external and internal stakeholders to integrate the solution