Audits of 106 plants in non-energy-intensive sectors find 17% energy savings potential, 303 GWh a year
An analysis of 106 on-site audits in sixteen sectors found an average economic efficiency potential of 17%. Heat recovery was the largest single contributor.
A study in Energy Sustainability and Society analysed 106 standardised on-site, technology-based energy assessments carried out between 2015 and 2024 in sixteen non-energy-intensive industrial sectors. The audited sites showed an average potential for economic energy efficiency improvement of 17%, equivalent to 303 GWh per year of savings biomedcentral.com
Energy Sustainability and Societybiomedcentral.comOpen source ↗. According to the publication's summary, the audits covered 74 firms with a combined baseline demand of 1,766 GWh per year.
Potentials were identified by comparing the equipment in place with the best available technology, which gives a bottom-up estimate of the efficiency gap. Earlier literature suggests a potential of 15–22%, but those studies are either bottom-up analyses of individual industries or cross-sectional top-down assessments. The authors say their data suggest a larger economic potential than is generally recognised.
Heat recovery and process optimisation lead the savings
Heat recovery contributed 4.2 percentage points of the total and process optimisation 3.8 percentage points. Component renewal added 2.2 and integrated heating and cooling concepts 1.5 percentage points. Heat recovery, either directly or via heat pumps, proved the most significant lever for reducing CO₂ emissions.
By energy carrier, the savings comprised 10.1 percentage points from natural gas, 5.9 from electricity, 0.8 from other fossil fuels and 0.3 from renewable inputs. The auditors recorded 868 efficiency potentials and 52 fuel-switching initiatives. Heat recovery accounted for 109 potentials averaging 0.7 GWh per year each, while 22 process optimisation measures averaged 3.1 GWh.
Costs and barriers
The sites were small to medium-sized, with annual demand of 1.5–60 GWh and a median of 4.8 GWh. Fewer than 10% of the plants had sub-meters beyond standard utility billing devices. Economic data were validated for 785 potentials, representing 273 GWh per year over a fifteen-year horizon.
The average specific cost of energy savings was 146 euros per MWh and the median 51 euros per MWh. Fully implementing the viable portfolio would give a weighted average net levelised saving of 44 euros per MWh. Measures with modest upfront capital, such as ventilation optimisation, energy monitoring and maintenance protocols, showed rapid returns. Building insulation and architectural changes yielded negative net returns unless tied to refurbishments, expansions or regulatory requirements.
The authors confirm that high discounting and a shortage of skilled personnel for implementation are the two main hurdles biomedcentral.com
Energy Sustainability and Societybiomedcentral.comOpen source ↗. For context, energy intensity improved by an average of 0.8% per year in 2000–2010 and 1.7% in 2010–2020, and rebound effects often negate such gains.
