In the automotive lubricant world, the focus is often on friction reduction and viscosity—necessary elements to improve fuel efficiency. But, in the chemistry of lubricants, a quiet fundamental shift is unfolding, one that may reshape the industry’s impact on the environment. This development, centred on reducing lubricants’ cradle-to-grave carbon footprint, has drawn attention from industry giants.
At the forefront of this push are re-refined base oils, or RBOs, challenging long-held beliefs that recycled oils are a poor substitute for virgin products. Once dismissed as lower-quality, RBOs have advanced in performance, positioning themselves as key tools for cutting carbon emissions in transportation.
At the recent Infineum Conference 2024 in Jaipur, Chris Locke, Executive Vice President of Commercial at Infineum, highlighted the substantial impact of this innovation. “You’ve also got the capability to introduce biocircular or, in some cases, refined bio-derived materials such as feedstocks in the additive package or the lubricant itself and that can, when you conduct an overall life cycle analysis, lead to the lubricant having up to 90% reductions in the carbon footprint of the material itself” Locke said, underscoring how lubricant composition has become as important to sustainability as viscosity or friction control.
Panelists at the conference included automotive industry leaders Alok Sharma, director of R&D at Indian Oil, and RM Petkar, president and CTO of Tata Motors. The session was moderated by Hormazd Sorabjee, editor, Autocar.
For Locke, the journey towards more sustainable lubricants involves two crucial areas: viscosity and friction modification, along with the materials used in lubricants. Reflecting on his 30-year career, Locke noted, “When I first came into the industry, monograde oils were extensively used, particularly in heavy-duty applications.”
Monograde oils, built to work efficiently within a single temperature range, have largely given way to multigrades such as 15W-40 and 10W-40. Multigrades offer viscosity versatility, with the “W” denoting “winter,” indicating the oil’s thickness at low temperatures.
Today’s innovations have introduced 5W oils, and research is even exploring ultra-thin 0W-20 oils with superior cold-weather performance and energy-saving potential. These low-viscosity oils are instrumental in improving fuel economy, particularly for heavy-duty engines where internal energy loss from churning can be substantial.
Passenger vehicles, by contrast, benefit most from reducing friction in high-stress components such as the valve train and ring pack. Advanced friction modifiers, ranging from metallic to non-metallic types, have become essential in achieving these efficiency gains.
Locke emphasized that reducing friction and improving viscosity, while critical, represent only part of the sustainability equation. RBOs, in particular, have transformed perceptions of lubricants by proving that recycled oils can match—if not surpass—virgin oils in quality. RBOs embody a “closed loop” approach, keeping carbon within an above-ground cycle, by recycling used materials rather than extracting new ones, which helps curb carbon emissions tied to oil production.
Locke explained that these bio-circular materials allow the industry to break from the traditional cradle-to-grave lifecycle, creating lubricants which are sustainable from production to disposal. This pivot towards bio-based innovation marks a subtle shift in how lubricant companies measure success: Where fuel efficiency and friction control once reigned, reducing environmental impact is now equally vital.
This dual approach—maximizing the lubricant’s efficiency within engines and advancing its sustainability profile, can play a foundational role in prolonging the relevance of the internal combustion engine (ICE) even as electrification gathers pace. Locke concluded that, while electrification remains a long-term goal, enhancing ICE sustainability offers a crucial pathway to reducing emissions in the near term. The pace of this transition, he noted, will vary by region, shaped by economic factors, geopolitics, and cost considerations.
As the industry retools, the humble lubricant has emerged as an unexpected ally in sustainable mobility, quietly driving a vision where engines run cleaner, waste is minimized, and carbon footprint of the oil itself is no longer overlooked. For an industry so often defined by power and speed, this patient work behind the scenes may ultimately prove to be most transformative.