food scraps (banana peel etc) in a compost bin
Image: Getty / Tina Tiller

BusinessApril 14, 2023

Why our food scraps are being driven hundreds of kilometres out of town

food scraps (banana peel etc) in a compost bin
Image: Getty / Tina Tiller

Councils are going to great lengths to avoid dumping 350,000 tonnes of food waste into landfills each year.

This story was first published on Stuff.

Auckland’s banana skins, potato peelings and other scraps are taking a three-and-a half hour road trip south to help ripen tomatoes instead of being buried in landfills.

A new kerbside food scrap collection rolling out across the super city this year at a cost of $25 million will see waste trucked more than 200km to the Ecogas​ plant in Reporoa​, where it will be processed into fertiliser for farmland and biofuel to heat T&G Fresh glass houses.

This war on waste is part of the government’s strategy to drastically reduce the 350,000 tonnes of food scraps going into landfills annually, and to cut down the greenhouse gases produced as that food rots underground.

At least a dozen new facilities will be needed to handle waste as the 2030 deadline looms for councils to provide kerbside food scrap collections in urban areas, and for businesses to separate food from general rubbish.

Auckland Council has begun providing homes with food waste recycling bins, like the one on the left (Photo: Supplied/Stuff)

Rubbish hits the road

According to a Treasury paper published last year, most of the country’s 67 local councils were either providing kerbside collections of food waste or intended doing so, and only 12% had ruled it out for now because of funding constraints or because their communities did not see it as a priority.

Auckland is far from the only local authority sending its waste long distances. Food scraps collected from New Plymouth District Council householders make a four-hour 300km journey to a composting facility in Waikato, Central Otago District Council will begin sending organic and food waste from 9500 households to Timaru for composting from July and Ecogas will start processing material from Manawatu next year.

At full capacity, up to five trucks a day will carry food waste from Auckland to Reporoa where they are unloaded, washed out, and make the return trip back-filled with aggregate for the construction industry.

Auckland Council general manager waste solutions Parul​ Sood​ says the council considered a “fogo” (food and green organic waste) collection, but it opted to focus on food scraps because of the sheer volume of Auckland’s green waste, and the fact the region already had a well established organics collection service provided by the private sector.

“There are lots of companies that do it, and they were very vocal in terms of their livelihoods not being impacted by an Auckland council service, which I guess the politicians took into consideration.”

Auckland Council general manager waste solutions Parul​ Sood (Photo: Supplied/Stuff)

It also made sense to have a facility located near the end users of its products – T&G’s massive tomato growing operation, and farms applying bio-fertiliser.

Sood says mixing food and organics limits you to composting, which has odour issues, and she hopes that eventually the amount of food scraps from various sources will make it viable for another anaerobic digester to be built closer to Auckland.

Digesting waste and avoiding a big stink

The Ecogas plant, New Zealand’s first large scale food waste to bioenergy facility, cost $42m to build with a $7m loan from the provincial growth fund. It can handle 75,000 tonnes a year of food scraps from food manufacturers and councils.

On arrival, the waste is driven into a huge shed for “de-bagging” by a machine that general manager Alzbeta​ Bouskova​ says is capable of picking out contaminants as tiny as coffee capsules, before chopping it up into a thick “smoothie” for bacteria to feast on. “It’s very similar to what happens in a cow’s stomach, burping to make methane.”

The resulting biogas, a mix of methane and CO2, can generate electricity, and next year Ecogas will feed methane into the national gas grid which fortuitously passes within 400m of the plant.

Bouskova​ says anaerobic digestion is particularly suited to food waste, such as dairy, meat and fish, because the smell can be contained. She believes Ecogas will set up at another three or four sites around the country over the next decade.

The anaerobic process is being “tweaked” so it can handle a mix of food and green waste, and Ecogas is interested in tendering for a facility to replace Christchurch’s compost plant, much maligned by nearby residents for its offensive smells.

Christchurch City Council reduced all maturing compost at the Living Earth compost plant in Bromley to address complaints about the smell (Photo: File/Christchurch City Council)

Waste Management, the country’s largest commercial composter, operates the problematic Christchurch facility and has also put its hand up to run a re-sited plant with six locations in contention.

Such is the demand for resource recovery and recycling, the company recently created a circular services division headed by David Howie to manage those activities.

He says Waste Management would not rule out getting into anaerobic digestion, but the plants are expensive and require large supplies of material to operate successfully, which is challenging in a country where the population is spread out, forcing material to be transported long distances.

Bouskova​ counters that by pointing out the trucking company carrying Auckland waste to the plant is decarbonising its fleet by introducing electric trucks and converting to CNG.

Levies charged on municipal landfills for household waste are increasing to $60 a tonne next year to help councils cover the not insignificant costs of new waste processing facilities.

As a result of those higher levies, Bouskova says gate fees at the Reporoa plant are lower than at landfills. “Lower enough that we can afford to truck food waste from Christchurch to Reporoa, and it’s still viable.”

She admits it would be a shame to transport South Island waste north, but if it made economic and environmental sense, it could be done.

Bouskova and Howie agree the government’s waste strategy is a good move because it gives clear direction on what is expected, and that gives the industry confidence to make long term large scale investments in facilities.

Business waste

The Ministry for the Environment has estimated that about a quarter of food scraps going into landfill are from businesses, and new legislation will require them to separate out food waste, a practice already well entrenched in some sectors. At Christchurch’s Te Pae convention centre, for example, excess food unsuitable for food bank donation goes through a dehydrator that turns it into a soil conditioner.

Restaurant Association chief executive Marisa Bidois says throwing food away is a last resort for hospitality businesses, and many have compost bins.

A survey found about 40% were dumping less than 5 litres a day, but almost a quarter were throwing away more than 10 litres daily. “Rounded up this represents 24,366 tonnes of food waste annually at a cost of over $5m across restaurants and cafes, which shows there is still more work to be done,” says Bidois.

Food waste makes up only 9% of waste sent to municipal landfills, but is responsible for 22% of their green house gas emissions (Photo: John Kirk-Anderson/Stuff)

Evironz began collecting food waste from Auckland businesses a year ago for composting, and chief operating officer James Rutter says demand is such that it is expanding the service to Waikato and Bay of Plenty. Most of its customers are in the commercial food area, but also include some offices.

The need to use a separate vehicle to collect food waste may increase the cost of rubbish disposal for general businesses, and a more appealing alternative may be to simply install garbage disposal units to flush it down the drain. That is a concern because, while some council waste water treatment systems can cope with that, many can’t.

The Ministry for the Environment estimates processing commercial food waste will require up to $38m of additional infrastructure, but initiatives such as the Foodprint app are attempting to stop leftovers ending up in the bin in the first place.

Foodprint connects 350 food outlets in Auckland, Waikato, Wellington, Nelson and Christchurch with 70,000 users who can snap up unsold items at discount prices, provided they are collected before the premises close.

App founder Michal Garvey says that like food rescue projects to feed the needy, Foodprint is preventing “a decent chunk” of waste from going to landfill. “The climate crisis is here, and we need to do whatever we can to reverse it. Stopping food waste is one of those activities.”

BusinessNZ opposed the mandatory nature of the government’s waste minimisation strategy, and advocacy director Catherine Beard says it wanted measures to be voluntary, especially since many councils are yet to get the “back end” of waste disposal sorted.

Environz’s Hampton Downs composting facility is fed by business and residential green waste and food scraps from all over the upper and central North Island (Photo: Environz)

In some US states mandatory collection of food scraps is limited to businesses that produce or sell food, while others include all businesses generating food waste above a certain level. Scottish businesses producing more than 5kg of food scraps per week have had to divert them from landfill since 2015.

Beard argues that international examples don’t work in New Zealand because of the geography of the country, and the number of small businesses where food makes up a tiny part of their waste stream, so it is a matter of finding solutions that are affordable, practical and effective.

“[Otherwise] you end up with a feel-good policy that costs a lot, but is not that impactful in terms of the problem you are trying to solve.”

The government has progressively increased the national waste disposal levy charged per tonne of material taken to landfill, and it now covers construction and demolition landfills as well as municipal ones taking household waste.

BusinessNZ says levy revenue has gone from about $36m in 2020 to $250m this year, and with half of it going to councils for waste minimisation projects, Beard would like more transparency over how it is spent.

The Ministry for the Environment says applications for more than $1m are assessed by an independent waste investment panel and minister David Parker makes the final decision. It currently has $120m in funding available, and has so far received 36 proposals for organic processing facilities, 12 of them in the South Island.

Kimberly Hope chairs the territorial authority arm of Waste Management Institute New Zealand (WasteMINZ) and she says councils are working together to address waste issues. In Taranaki, where she is the resource recovery manager for the New Plymouth District Council, three councils and major food processors are planning an organics processing facility that would do away with the need to transport waste out of the region.

In small towns where there is no commercial food waste collection for businesses, one option is for councils to charge businesses a targeted rate for inclusion in residential kerbside services, but Hope is unsure how that would work because of the volumes involved. “They might need larger receptacles, they might need one or two collections a week, and the more diversity you offer, the higher the cost to deliver those services.”

Hope says it is unfair to lump more costs on to ratepayers. “Businesses should take responsibility for their waste and pay for it themselves, councils can assist in making sure services are available, but they don’t necessarily need to provide them.”

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