How to reduce CO₂ emissions in industry: strategies for effective decarbonisation

To reduce CO2 emissions in the industry, it is necessary to combine measures such as improving energy efficiency, electrification of processes, the use of renewable fuels, heat recovery and other decarbonisation technologies. The most effective strategy depends on the characteristics of each facility and its main sources of emissions. 

What you need to know about the reduction of CO2 emissions in the industry:

• Effective decarbonisation does not depend on a single isolated solution, but on a hierarchical roadmap that begins with energy efficiency and culminates in the technological substitution of the thermal vector.
• Given that about 70% of industrial energy consumption produces heat and steam, decarbonizing thermal energy (with biomass, electrification or recovery) generates the greatest immediate impact on scope 1 emissions.
• Many priority measures generate direct savings in the energy cost that amortizes the capital invested in highly competitive time windows.
• The implementation of technologies without continuous digital measurement lacks traceability to audit the sustainability indicators and the ESG criteria required by global markets.

Why is it important to reduce CO2 emissions in the industry?

Reducing CO2 emissions in industry is essential to mitigate climate change, ensure compliance with European environmental regulations, and improve business competitiveness. The transition to clean and efficient energy sources allows factories to reduce their energy costs, protect themselves from the volatility of the price of fossil fuels, and respond to the growing sustainability demands (ESG) of investors, customers and international markets.

The importance of reducing CO2 emissions in the industry lies in:

• Environmental impact: Mitigates climate change, preserves natural resources and improves air quality.
• business competitiveness: Protects commercial margins against the volatility of fossil fuel prices.
• Regulatory compliance: Avoid administrative sanctions and closures when adapting to European regulations such as the Green Deal or the CSRD Directive.
• ESG requirements: Facilitates access to bank financing and improves positioning in global value chains that prioritize sustainability.
• Economic efficiency: Generates structural savings in energy by replacing inefficient fuels and residual heat recovery.

Where do CO2 emissions come from in an industrial plant?

To articulate an effective mitigation strategy, it is necessary to map and classify the greenhouse gas generation points within the contours of the factory.

Combustion of fossil fuels

Represents the largest source of direct emissions (Scope 1). They come from the burning of natural gas, fuel oil, diesel or coal in boilers, steam generators, dryers and process thermal furnaces.

Electricity consumption

Falls within indirect emissions (Scope 2). It occurs due to the consumption of electricity from the commercial network when the national electrical mix still contains fossil sources for the generation of driving force, lighting and refrigeration systems.

Industrial processes

Emissions not associated with energy, but with chemical reactions of the raw material itself during the production process (such as the decarbonation of limestone in the cement or limestone industries, or reactions in the chemical synthesis).

Internal transport

Use of forklifts, auxiliary vehicles and maintenance machinery powered by internal combustion engines within the industrial enclosure.

Energy losses

Heat leaks in non-insulated steam distribution networks, condensates discarded to the sewer, compressed air leaks and inefficiencies in the heat exchangers that force to burn more fuel than strictly necessary.

How to reduce CO2 emissions in industry: priority measures

1. Improve energy efficiency

The cleanest and most economical energy is not consumed. Energy efficiency is the first logical step in any decarbonisation plan.

• Energy audits: Deep field diagnoses in accordance with ISO 50002 to identify leaks, inefficiencies and optimization opportunities in the plant processes.
• Process optimization: Adjustment of the operating parameters (air-fuel ratio in burners, working pressures, load curves) to maximize the performance of existing machinery.
• Automation: Intelligent control of starts, stops and modulation of operational loads depending on the actual production rate.
• Consumption monitoring: Installation of telemetering and subcounting to detect deviations in real time and correct abnormal consumption patterns.

2. Electrify industrial processes

It consists of replacing gas-powered equipment or petroleum derivatives with clean electricity powered systems (backed by photovoltaic self-consumption or renewable PPAs).

• Industrial heat pumps: High-efficiency equipment that harnesses environmental thermal energy or low-temperature residual heat to raise them (up to 150ºC), producing hot water and steam at low cost with a high POP.
• Electric boilers: They generate hot water and process steam through resistors or electrodes, offering a performance close to 100% and immediate response.
• Replacing fossil equipment: Gradual replacement of gas burners by induction, infrared or electric arcs in processes where it is technically viable.

3. Replace fossil fuels with renewable energy

For the generation of medium and high temperature heat where electrification is not economically viable, fuel substitution is the key strategy.

• Industrial biomass: The most mature and competitive solution for the generation of steam and uninterrupted hot water (24/7). By using local solid biofuels (chips, pellets, agricultural by-products), it eliminates up to 100% of direct scope 1 emissions.
• Biomethane: Purified biogas from the recovery of organic waste that is injected into the existing gas network without the need to modify the current boilers or infrastructure.
• Synthetic gases: obtained by pyrolysis and metanation processes combining hydrogen with CO2 captured from sources of the industrial process.
• Renewable hydrogen: Energy vector without carbonaceous emissions designed for its integration in the medium and long term in high-temperature industrial processes.

4. Recover waste heat

Energy integration avoids the useless generation of new energy by taking advantage of the remaining thermal mass of the process itself.

• Energy Reuse: Heat capture in chimneys, boiler purges and exhaust gases to preheat inlet water to generators or combustion air through economizers.
• Thermal use: Recovery of hot liquid effluents through plate exchangers to preheat washing or purification processes.

5. Digitize energy management

Digital transformation is the enabler to optimize savings measures.

• IoT sensors: Deployment of the network of sensors to monitor flow, pressure, temperature and electrical consumption at each critical point of the factory.
• artificial intelligence: Predictive algorithms that automatically adjust the operation of the thermal power plant according to the weather conditions and the production plan.
• EMS Systems (Energy Management Systems): Software platforms under ISO 50001 that integrate energy management within executive decision making.
• Digital Twins: Virtual installation replication to simulate energy optimization scenarios without altering actual production.

6. Incorporate carbon capture when necessary

CCU technologies (Carbon Capture, Utilization and Storage) allow capture CO2 by fireplace before being released into the atmosphere. This solution is oriented to sectors with inherent process emissions that cannot be eliminated only by substituting fuel (such as the production of cement, lime or steelwork).

What measures offer greater economic savings?

Not all CO2 emission reduction or elimination measures require the same volume of capital or offer the same amortization terms. The following table reflects the general investment and return trends for industrial projects:

The balance between the initial investment and the reduction of operating costs is the determining factor in calculating the real return of the transition. To know in detail the direct impact on the income statement of your factory, we recommend that you read our analysis of the Economic benefits of industrial decarbonization.

How to Prioritize Investments to Reduce Emissions

To ensure that capital deployment gets the maximum environmental and economic return, it is essential to follow a phase-structured methodology:

Energy diagnosis

Carry out a detailed technical audit to quantify real consumption, identify the inefficiencies of current equipment and evaluate the viability of the physical plot to house new infrastructures.

Identification of emissions

Measurement of the carbon footprint according to its sources (Scope 1, 2 and 3) to prioritize interventions in the spotlights where most of the fossil fuel is burned.

Technical-economic evaluation

Analyze each measurement by calculating the cost of tonne of CO2 avoided. The return period must be evaluated (Payback), the net present value (VAN) and the financing alternatives of projects without direct investment.

Implementation Roadmap

Design a phased schedule that begins with the quick execution measures (Quick wins of energy efficiency), continue with the substitution of the main thermal vector (biomass or electrification) and plan advanced long-term technologies. If you want to delve into how to design this strategic document, see our guide on how to write a industrial decarbonization plan.

Monitoring through indicators

Establish key performance indicators (KPIs) such as thermal kWh consumed per unit of final product or tons of CO2 per batch manufactured to verify the reductions achieved.

What technologies allow you to reduce more emissions depending on the type of industry?

Each productive sector has pressure, temperature and operational profile requirements that condition the optimal decarbonization technology:

How ENSO develops an emission reduction project

On ENSO We accompany the industry in each step of the energy transition process, acting as a technological, operational and financial partner to materialize what it means to define what is Industrial Decarbonization in productive reality.

• INITIAL AUDIT: We analyze in situ the thermal and electrical consumption profiles of your factory to identify the opportunities of greatest impact.
• Detail Engineering: We design the custom technical solution (biomass plants, heat recovery plants or electrification), optimizing hydraulic integration with your collectors without interrupting production.
• Technological selection: We choose the best combustion, filtering and digitization equipment adjusted to current environmental regulations or the ideal hybridization of the different technologies.
• Implementation and financing (ESE model): We assume the complete execution of the project. Through our energy services company model, we finance 100% of the initial investment (ZERO CAPEX for the plant), selling only the required thermal energy at a long-term guaranteed competitive rate.
• Results Tracking: We manage the operation of the plant, preventive maintenance and continuous analytics to certify the effective reduction of emissions.

If you want our team of engineers to analyze the feasibility of decarbonizing your plant, you can learn more about our services. Industrial decarbonisation or request a preliminary study.

Frequently Asked Questions

What is the fastest way to reduce industrial emissions?

The fastest way combines Immediately executed energy efficiency measures (Insulation, combustion adjustment, elimination of leaks) With the replacement of the fossil boiler with a industrial biomass, which allows to eliminate up to 100% of direct scope 1 emissions in a few months.

Is it possible to reduce emissions without replacing the entire installation?

Yes. There are progressive strategies such as the incorporation of Residual heat recovery equipment On the current chimneys, the hybridization of existing boilers with biomethane burners or the installation of heat pumps to cover the low temperatures, keeping the fossil boilers as initial backup.

What technology does the highest return on investment offer?

The Waste Heat Recovery and the Industrial biomass They offer return periods of less than 5 years. With biomass under ESE model, the plant obtains a Savings from the first year without initial investment, which is the responsibility of the energy partner.