Life cycle carbon footprint of re-refined oil vs. base motor oil

Engine oil

Engine oil


Abby Kirchofer

PhD, Senior Managing Consultant
T: +1 415 426 5013
Ashley Kreuder

Ashley Kreuder

Managing Consultant
T: +1 303 382 5483

The re-refining of used motor oil is intended to minimize or avoid emissions of greenhouse gases comparable to levels associated with either extracting and processing crude oil or other recycling methods for managing used motor oil. 

Revising tool with new data

Ramboll was asked to quantify GHG reductions associated with re-refining used motor oil by determining the life cycle carbon footprint associated with one gallon of re-refined base oil and contrasting that with the life cycle carbon footprint of an equivalent product derived from virgin stock that is not re-refined. 

Ramboll’s work is on-going and involves revising the initial life cycle carbon footprint associated with the re-refining process using new primary data, new emission factors, and new estimates of global warming potential and will incorporate any updates to relevant standards that have been published since the initial life cycle carbon footprint.

Life cycle carbon footprint reduction of 81%

Ramboll’s work showed the life cycle carbon footprint associated with re-refined base motor oil is 81% lower than virgin stock-derived base motor oil. Ramboll’s work also showed how re-refined base motor oil and virgin stock-derived base motor oil carbon footprints can vary significantly depending on model assumptions. Yet even in the worst case, the re-refining process resulted in less than half of the GHG and carbon emissions associated with virgin stock-derived base motor oil. 

Emission reductions and public education

The results also revealed that the most significant advantages of re-refining occur during the base oil production and waste management life cycle phases. Ramboll’s results are being applied to set target emission reductions and to educate consumers and public policy makers on the potential environmental benefits of using re-refined base motor oil.

International standards and guidelines

The carbon footprint analysis included estimation of GHG emissions associated with raw material extraction and processing, transportation, manufacturing and waste management. Ramboll’s analysis was conducted in accordance with ISO 14040/14044 and PAS 2050 guidelines as confirmed by a third-party review panel. This included determination of the goal and scope of the study; development of a life cycle inventory that included all inputs and outputs associated with the re-refined base oil and virgin base oil, and development of a carbon footprint model. 

The carbon footprint results were calculated using the IPCC Fourth Assessment Report Global Warming Potentials. Carbon emissions were reported for each re-refining process, key contributor and life cycle stage. A sensitivity analysis was conducted to capture uncertainties and capture the range of results associated with variations in transportation, fuel efficiency, and waste management.

The analysis was published for public, technical and regulatory audience in the American Chemical Society journal, Sustainable Chemistry and Engineering.  

Ramboll Group A/S

Ramboll Group A/S
Hannemanns Allé 53
DK-2300 Copenhagen S
Tel:+45 5161 1000
Fax:+45 5161 1001

Danish CVR numbers

Danish CVR numbers

Ramboll Group

Rambøll Danmark

Ramboll Energy

Rambøll Management Consulting

Other sites

Other sites