Fonterra insists efforts to transition its Te Awamutu milk processing site from being coal-powered to using wood pellets are "full steam ahead", with commissioning underway.
Last year the dairy co-op announced it would begin to slowly transition away from coal, putting a stop to installing any new coal boilers or increasing capacity to burn coal.
And in January the company said it would be investing $11 million to transition Te Awamutu - its sixth largest site - to a more sustainable, wood-pellet burning operation.
On Wednesday, Fraser Whineray - Fonterra's chief operating officer - said despite the COVID-19 pandemic presenting some challenges, the company had still managed to complete the decarbonisation project before spring milk arrived.
"We did have some delivery delays with certain offshore components, and I'm pleased with the outcome thanks to our team and suppliers," said Whineray.
"It's really important sustainability investments like this are maintained despite the pandemic challenges."
Fonterra says once completed, the transition at the Te Awamutu plant will reduce its national coal consumption by almost 10 percent, saving more than 84,000 tonnes of carbon emissions per year - the equivalent as taking 32,000 cars off the road.
In announcing its intentions last year, Fonterra said it was aiming to reduce its emissions by 30 percent across all operations by 2030 and achieve net-zero by 2050.
But getting out of coal, the company said, "is not as easy as flicking a switch", and required a stage approach.
That approach has been criticised by environmental activists, who say the company needs to do more.
In July protesters from Extinction Rebellion protested the co-op's Christchurch offices after Bathurst Coal applied to expand the Canterbury Coal Mine, which sends a majority of its coal to Fonterra. The group said the move showed Fonterra wasn't sticking to its pledge and needed to be held accountable to the public for its ongoing coal use.