Energy Efficiency in the Chemical Industry

The chemical sector ranks among the top industrial areas in global energy consumption. According to the International Energy Agency (IEA), the chemical sector is the industrial subsector that consumes the most oil and natural gas; however, it ranks third in direct CO2 emissions, behind the iron-steel and cement sectors. The main reason for this is that approximately half of the sector's energy input is used not as fuel but as feedstock (IEA – Chemicals).

According to a study published in ScienceDirect, the chemical and petrochemical sector constitutes 30% of industry's total final energy consumption, making it the largest energy user in industry; however, due to the complexity of the sector, its energy efficiency potential is not fully understood (Saygin et al., ScienceDirect). According to data from the U.S. Energy Information Administration's (EIA) Manufacturing Energy Consumption Survey (MECS), chemical industries account for approximately 29% of total energy consumption (including fuel and feedstock use) in the U.S. manufacturing sector (EIA – Chemical Industry Analysis Brief).

The Sector's Energy Profile and Emission Structure
According to IEA data, the largest share of emissions in primary chemical production comes from ammonia production (45%), followed by methanol (28%) and high-value chemicals — ethylene, propylene, benzene, toluene and mixed xylenes (27%). Coal accounted for an estimated 36% of process energy used in primary chemical production in 2022 (IEA – Chemicals). According to a technical review published on the Oil & Gas Portal, the main energy-consuming processes — steam cracking, ammonia production from natural gas and coal, aromatics extraction, methanol and butylene production — account for approximately 70% of the sector's total consumption. This study states that the chemical and petrochemical sector contributes approximately 7% to global CO2 emissions (Franchi, Oil & Gas Portal).

Key Technologies and Applications for Improving Energy Efficiency
Equipment-Based Efficiency Measures: The same technical review lists concrete efficiency measures for boilers, heat exchangers, steam distribution systems, electric motors and distillation columns: pretreatment of boiler feed water, reduction of excess air using flue gas analyzers, prevention of fouling in heat exchangers, use of variable speed drives (VSD), optimization of reflux ratios in distillation, and replacement of old columns with Divided Wall and Heat Integrated columns (Franchi, Oil & Gas Portal).

Product-Based Efficiency Applications
Specific applications such as the use of sulfur-based inhibitors to reduce coke formation in ethylene production, the use of ceramic-coated furnace coils and gas turbine integration; and the use of power and steam obtained from cogeneration in polymer production are detailed in the same source.

Catalyst Development and New Processes:
In a joint study conducted with the International Council of Chemical Associations (ICCA) and DECHEMA, the IEA estimates that catalyst and related process improvements could reduce energy consumption by 20-40% by 2050. New methods such as the Methanol-to-Olefins (MTO) process and the Hydrogen Peroxide-Propylene Oxide (HPPO) process provide approximately 10-12% energy savings compared to conventional processes (Franchi, Oil & Gas Portal).

Electrification:
According to ACEEE's report “Transformative Policies to Reduce Chemical Industry Carbon Emissions,” slightly more than 30% of the chemical industry's heating demand is below 300°C — a temperature range that can be directly electrified with technologies commercially available today. The report notes that programs such as the U.S. Department of Energy's (DOE) Industrial Heat Shot initiative support the research and development of alternative process heat technologies to fossil fuel combustion (ACEEE – Transformative Policies).

High-Temperature Heat Pumps and Waste Heat Recovery:
In an example cited by the IEA, at a chemical plant in the United Kingdom, a 12 MW heat pump recovers waste steam at 152°C, raising its temperature to 211°C and achieving a coefficient of performance (COP) of 5.3. Approximately 80% of process heat below 200°C (which corresponds to approximately 25% of total process heat) can be met with such heat pumps (IEA – Chemicals).

Steam Systems and By-Product Recovery:
According to EIA's MECS data, approximately 43% of the “other fuels” category in the U.S. chemical industry consists of by-products arising from production processes; 96% of this is waste gas. This waste gas is generally recovered for steam generation, preheating via heat exchangers, and providing heat to other processes (EIA – Chemical Industry Analysis Brief). ACEEE's 2000 report “Emerging Energy-Efficient Industrial Technologies” also lists steam system assessment tools and the optimization of steam systems in the chemical industry among prominent efficiency practices (ACEEE – Emerging Energy-Efficient Industrial Technologies).

Carbon Capture, Utilization and Storage (CCUS) and Electrolytic Hydrogen:
The IEA states that CCUS and electrolytic hydrogen are the main pathways for decarbonization in the sector. In the NZE Scenario, the chemical sector is expected to account for approximately 5% of total CO2 captured and 11% of low-emission hydrogen consumption by 2030; however, current infrastructure falls well short of these targets (IEA – Chemicals).

Material Efficiency and Recycling
According to the IEA, recycled plastics account for only approximately 8% of total global plastic production. An increase in this ratio would directly reduce the need for virgin polymer production and thus energy demand. Mechanical recycling is generally preferred over chemical recycling due to its lower energy consumption, but the purity level of waste plastic limits the applicability of this method (IEA – Chemicals).

Policy and Sectoral Initiatives
The European Union has the highest number of electrolysis-based ammonia and methanol production projects in the world, and also has the highest plastic recycling rates. 

France published a roadmap in 2021 for the decarbonization of the chemical industry, setting a target of a 31% reduction in emissions by 2030; the United Kingdom and Germany announced similar roadmaps in 2015 and 2019, respectively (IEA – Chemicals). The ACEEE report emphasizes that transformative policy proposals aimed at reducing chemical sector emissions in the U.S. — including electrification incentives, carbon pricing and federal R&D investments — can accelerate decarbonization while preserving the sector's competitiveness (ACEEE – Transformative Policies).

Evaluation in the Context of Türkiye
In Türkiye, the chemical sector has a natural gas- and electricity-intensive production structure, and fluctuations in energy costs shorten the payback periods of efficiency investments such as waste heat recovery and process optimization. For chemical producers exporting to the EU, regulations such as the Carbon Border Adjustment Mechanism (CBAM) make energy and carbon efficiency mandatory from a competitiveness standpoint as well. The equipment-based measures outlined above (use of VSDs, steam system optimization, heat recovery) offer directly applicable gain areas for local facilities as well, with low investment costs.

Conclusion
Energy efficiency in the chemical industry plays a decisive role both in reducing operating costs and in achieving global climate targets. Data from the IEA, EIA, ACEEE and academic sources show that the sector's energy-intensive structure can be significantly improved through multidimensional strategies such as equipment-level optimization, waste heat recovery, electrification, fuel switching, catalyst development and recycling. However, current infrastructure investments — particularly CO2 storage and hydrogen pipeline networks — remain far from the scale required by the NZE Scenario. Accelerating technological investments in the sector over the next decade, supported by regulatory frameworks, will be key to sustainable transformation.

Sources

1. IEA – Chemicals, Energy System / Industry

2. EIA – Manufacturing Energy Consumption Survey (MECS), Chemical Industry Analysis Brief

3. Saygin, Patel et al. – “Potential of best practice technology to improve energy efficiency in the global chemical and petrochemical sector”, ScienceDirect / Energy

4. Franchi, G. – “Practice and Technology and Measures For Improving Energy Efficiency in the Chemical and Petrochemical Sector”, Oil & Gas Portal

5. ACEEE – “Transformative Policies to Reduce Chemical Industry Carbon Emissions”

6. ACEEE – “Emerging Energy-Efficient Industrial Technologies” (Research Report IE003)