GLIDE facility turns used oil into new base oil, saving an estimated 100,000 tonnes of CO2 a year.

For decades, all of the waste engine oil collected in New Zealand has been burned, much of it as fuel for industrial heat processes. From today, it can be recycled into new oil instead.

GLIDE has officially opened New Zealand’s first oil re-refinery at its site on Subway Road, Pukekohe. The facility takes used oil from mechanics’ workshops, car dealerships and fleet operators across the country and re-refines it into high-quality Re-Refined Base Oil (RRBO), ready to be blended into new lubricants and used again.

GLIDE General Manager John Knox says the opening changes what happens to one of the country’s most common waste products.

“Every oil change in New Zealand has ended the same way. The old oil gets collected, and then it gets burned. It’s a valuable resource, and we’ve been setting fire to it. This plant means that oil can now become new oil again, right here in Pukekohe.”

“We’ve been handling waste oil on this site since 1984, and our team has spent years getting this plant from concept to fully operational. We wanted to prove the plant and set a pathway towards optimisation.”

Burning waste oil for heat releases the carbon it contains straight into the atmosphere, along with other pollutants from the additives and contaminants the oil picks up in engines. Once it is burned, the oil is gone for good, and new base oil has to be made from crude oil to replace it.

Re-refining breaks that cycle – the oil is kept in use rather than burned, and every litre of re-refined base oil reduces the need for new oil refined from crude, an energy-intensive process that New Zealand relies on imports for.

The emissions benefit

GLIDE’s re-refining is estimated to potentially save up to 100,000 tonnes of CO2 each year, the equivalent of 17,000 one-way journeys between Wellington and Auckland. The calculated carbon savings have been independently verified by Toitū Envirocare.

GLIDE Executive Director Gavin Thomas says the facility gives New Zealand a significant new tool for cutting emissions.

“For decades, New Zealand has had no choice but to burn its waste oil. Being the first facility of its kind here means we can finally change that. Taking potentially 100,000 tonnes of carbon out of the picture each year is a real, measurable result, and it happens simply by recycling something we were already collecting.”

“For workshops, dealerships and fleet operators, it’s a straightforward way to know their waste oil is being recycled, not burned. That matters to their customers, and it matters to their own emissions reporting.”

How re-refining works

Re-refining is different from filtering used oil or burning it for heat. The oil is taken back to its base components and cleaned to a standard comparable with virgin base oil. At GLIDE’s plant the process runs in four main stages:

1. Collection and testing: used oil is collected from GLIDE customers nationwide and tested on arrival to check its quality and screen out contaminants.
2. Pre-treatment: water, fuel residues and solids are removed from the oil.
3. Vacuum distillation: the oil is heated under vacuum to separate the valuable base oil from heavier residues, which are recovered for use as light cut, middle distillate and asphalt extender.
4. Finishing: the base oil is treated to remove remaining impurities producing a clear, high-quality Re-Refined Base Oil ready to be blended into new lubricants.

Waste oil contains a range of components – around 70% of which is base oil. Because base oil does not wear out, only the additives and contaminants do, it can be re-refined many times over, with about 99% of the waste base oil able to be re-refined and reused indefinitely. The remaining 30% consists mainly of water, light cut, middle distillate and asphalt extender. Through GLIDE’s advanced refining process, these are also recovered and repurposed – ensuring almost 100% of waste oil is reused.