Dairy giant Fonterra is under fire for its enthusiastic use of coal to fire its milk drying plants, with a joint Action Station and Coal Action Network Aotearoa (CANA) petition urging people to sign an open letter to Fonterra Chair John Wilson.
Coal has long been recognised at the worst offender for climate change and, rather than wean itself off it, Fonterra has actively been investing in both coal-fired milk drying plants and coal mines.
According to Action Station, Fonterra is New Zealand's second biggest coal user, burning more than half a million tonnes a year. Its coal use has increased 38% since 2008.
Action Station also says that Fonterra is planning a big increase in its use of coal.
"It plants to build more coal boilers to let it dry even more milk powder. That's really bad news for our climate.
"Fonterra wants to be seen as clean and green. It doesn't want to be branded as a climate criminal. If enough of us speak up now, we can turn Fonterra's plans around. And that's why Coal Action Network Aotearoa and Action Station have launched this sign-on letter campaign."
Fonterra doesn't have to use coal. It could use wood waste instead, says CANA.
"Fonterra has just applied for consent to build a huge new milk drying plant at Studholme in South Canterbury with four new coal boilers. But there are other ways of getting the heat it wants.
"In forests around the region, mountains of waste wood - branches, broken logs, prunings - are burned on site or left to rot. There are companies who collect this and supply it as fuel to industry. It is being used already in greenhouses, hospitals, schools, and other industries around the country.
"Fonterra - like the rest of the world - needs to phase out coal. But the decision point is when you design the boiler. To get the best performance, and to be able to use the cheapest fuel, the boiler needs to be purpose-designed for wood.
"Designing these four new boilers at Studholme for coal will commit Fonterra to increased coal use for at least another 40 years."
Fonterra, however, believes the campaign to be misinformed. A spokesperson from the company said that there simply isn't enough wood waste in New Zealand for their needs and, even it there was, the "technology does not yet exist" for a plant such as the proposed Studholme unit to be fired by wood chip.
Grant Smith, GM of business development and strategy for Pioneer Generation, a company specialising in renewable energy generation and, in particular, wood-chip-fired boilers, broadly agrees, but says Fonterra certainly could be doing more with its smaller units.
"A ten MW boiler is getting near the top of what's being done in New Zealand, apart from the big one at Kinleith, which I think produces 100MW of heat and 30MW of electricity. So it's possible, but the larger the unit, the bigger the distance your fuel has to come from the surrounding area - like an onion, and the higher the costs. It's a complex argument," says Smith.
"Where they can use wood is particularly for auxiliary or small plants, and bring down their emissions, that would be a good start. That's quite doable. They certainly could be doing better."
Laura O'Connell Rapira, campaigns director at Action Station, says that wood supply merchants have have informed Action Station that they could supply enough waste wood for the new proposed plant at Studholme. A wood industry expert has also calculated that there is enough waste wood within economic distance to feed the three North Island plants in the Waikato.
Action station also points to examples of very large biomass boilers around the world - ranging from 750MW to 125MW.
"If Fonterra commits to and follows through on a programme to progressively convert existing boilers to use wood waste, that will help grow the forestry industry and forestry jobs," she says.
The campaign plan is to deliver the letter before the Fonterra Board meets in late November.
Check out the campaign here