As Europe’s automotive industry accelerates towards electrification, even the smallest technical decisions can have major consequences. Automotive parts expert Marianna Lazaridou explains why compressor oil has become one of them.
The transformation of Europe’s automotive landscape is well underway. Hybrid and fully electric vehicles are no longer a niche category but a defining force shaping the future of mobility. With this evolution comes a new generation of technologies, components and maintenance standards that require greater technical knowledge than ever before.
Few professionals have witnessed this transition as closely as Marianna Lazaridou, who has spent more than two decades in the automotive parts industry, working alongside workshops, distributors and manufacturers while following the rapid evolution of aftermarket technology. Having observed the industry’s shift from conventional internal combustion engines to electrified powertrains, she believes that many of the most costly repairs stem not from major mechanical failures, but from seemingly minor maintenance decisions. As hybrid and electric vehicles become an increasingly significant part of Europe’s vehicle fleet, understanding the different lubrication requirements of modern air conditioning compressors has become essential for technicians and aftermarket professionals alike.
Question: The market is dominated by two types of compressor oils—PAG and POE. What distinguishes them?
Marianna Lazaridou:
The distinction lies primarily in the type of compressor and the vehicle manufacturer’s specifications.
PAG (Polyalkylene Glycol) has long been the industry standard for conventional vehicles equipped with mechanically driven compressors powered by the engine belt. It performs exceptionally well under high operating pressures and is fully compatible with refrigerants such as R134a and the newer R1234yf.
As the industry has moved towards hybrid and fully electric vehicles, manufacturers have increasingly adopted electrically driven high-voltage compressors. These systems require electrically insulating lubricants, and in many applications POE (Polyol Ester) has become one of the most widely used solutions. However, some manufacturers specify other dielectric lubricants, such as PVE or specially formulated oils, which is why technicians should always follow the OEM specification rather than relying on general assumptions.
As Europe’s vehicle fleet continues to electrify, understanding these differences has become an essential part of modern vehicle servicing.
Question: Electric and hybrid vehicles have introduced entirely new technical challenges. Why is POE indispensable in these applications?
Marianna Lazaridou:
The first thing to remember is that the manufacturer’s specification always comes first. Many high-voltage electric compressors require electrically insulating lubricants, and POE is one of the most commonly specified oils for these applications. However, some manufacturers specify alternative dielectric lubricants, so it’s important never to generalize.
Unlike conventional compressors, electric compressors integrate a high-voltage electric motor within the compressor housing itself. Because of this design, the lubricant must not only provide effective lubrication but also electrical insulation.
Where POE is specified, its dielectric properties help protect the motor windings while ensuring reliable compressor performance. It’s a detail many professionals never think about, but one that is fundamental to both safety and long-term reliability.
Final answer
The biggest lesson is that modern vehicles should never be approached with yesterday’s assumptions.
Every vehicle should be serviced according to the manufacturer’s specifications—not only regarding refrigerant, but also the exact type and viscosity of compressor lubricant. Whether it’s a conventional petrol car, a hybrid or a fully electric vehicle, there is no universal solution.
As automotive technology evolves, technical knowledge becomes just as valuable as the parts themselves. Often, it’s the smallest maintenance decisions that determine whether a repair provides years of reliable operation or results in a costly failure.
Need the Right Compressor Oil?
Choosing compressor oil isn’t simply a matter of choosing between PAG and POE. The correct lubricant depends on the compressor, refrigerant, vehicle application and, most importantly, the manufacturer’s specification.
If you’re servicing a vehicle and already know which specification you need, you can find the appropriate compressor oils directly through the Soferina Shop.
Check the vehicle manufacturer’s specification or the compressor manufacturer’s recommendation before selecting an oil. Using the wrong lubricant can affect compressor performance and, in high-voltage systems, may have serious consequences.
