Waste to energy plants a bad answer to the wrong question

Thursday, 11 July 2024

A file photo of rubbish being dumped at Canterbury’s Kate Valley landfill. Hannah Blumhardt argues that surplus rubbish is better disposed of in landfills rather than incinerated to generate electricity, as two proposed projects for New Zealand intend.

Hannah Blumhardt is Engagement and Research Associate at Sustainability, Te Herenga Waka - Victoria University of Wellington.

OPINION: There’s a saying amongst those who work in waste minimisation that “if recycling is the answer, you’re asking the wrong question.”

The point being that the negative environmental impacts of waste don’t just appear the moment waste is created and discarded. Rather, every piece of rubbish represents the endpoint of a supply chain of environmental harm that is already baked into that rubbish. Recycling alone cannot resolve this.

This embodied impact includes the energy and pollution from extracting natural resources, the chemical additives that transform those raw materials into products, the carbon emissions from shipping (mostly short-lived) stuff around the world, and so on.

According to the 2024 United Nations Environment Programme’s Global Resources Outlook, the world has a serious overproduction problem. Natural resource consumption now exceeds 100 billion tonnes a year. Material extraction and processing accounts for over 50% of global emissions and 90% of biodiversity loss. Of all materials extracted, roughly 60% is used for physical stuff, and at least a fifth becomes waste within the year.

Even a magical end-of-life solution to “get rid of” our rubbish wouldn’t erase the damage already done to create it. Avoiding that harm requires redesign of products and of production and consumption systems to reduce how much material we draw into the economy, slow down the pace at which those materials pass through the system, and ultimately stop making so much rubbish in the first place.

We can do this by regulating for, and investing in, durability, reusability and repairability of essential items, and phasing out and divesting from items and business models that we don’t need. We can better value public infrastructure that enables more efficient sharing of resources (eg public transport, libraries etc.). We can improve recycling by adopting more recyclable materials and better, producer-funded collection systems for retrieving them.

Ultimately, reducing waste, plastics and associated harms means rethinking the economy and our priorities. There’s no technofix for this.

Now, imagine that the proposed answer to our waste woes was not any of the above, but simply a facility to make waste “disappear” by burning it and extracting a one-hit microdose of dirty energy.

Currently, two small rural New Zealand towns face exactly this proposition: active proposals for large “waste-to-energy” incinerators on their doorstep.

In Waimate, South Canterbury, the joint venture, SIRRL, has lodged consents for a plant to burn 350,000 tonnes p/a of mixed solid waste, trucked in from across the South Island, to produce 30MW of electricity (0.3% of New Zealand’s current installed generating capacity).

Last year, the Environmental Protection Authority (EPA) advised that the consent is nationally significant, due to factors including: elevated public concern, significant proposed use of natural and physical resources, and potential climate emissions and pollution. Consequently, the Minister for the Environment “called in” the consent application for decision by the Environment Court.

Meanwhile, in Te Awamutu in the Waikato, local company Global Contracting Solutions has proposed a plant to burn 150,000 tonnes annually of mixed solid waste, tyres and flock. The consent application has instigated community protests in the streets, and almost 900 public submissions (the most the council has ever received on any matter). As with Waimate, the EPA has determined the proposal is nationally significant and recommended the minister call in the consent application.

Are these proposed plants a good idea? The fact New Zealand doesn’t have any waste-to-energy facilities for household rubbish causes proponents consternation. However, closer inspection suggests we might actually be “far enough behind to be ahead”.

Overseas, countries that rely on incinerators are staging a managed retreat, particularly in Europe. For example, Scotland and Wales have placed moratoria on new waste-to-energy plants. England temporarily paused new permits in May, which the UK Conservative Party proposed making permanent in its 2024 election manifesto. Denmark, the waste-to-energy poster-child, will close seven facilities to reduce incineration capacity by 30% by 2030.

For New Zealand to move in the opposite direction and lock ourselves into expensive waste disposal plants that we don’t have already seems unwise, especially given the urgent need to redirect available funds and ingenuity towards new systems that help reduce our upstream and downstream waste footprint.

A waste to energy plant built by Danish engineering company Ramboll.

Plants that torch our weekly trash literally burn up resources and risk worsening our contribution to global overproduction, climate change, plastic pollution and waste generation.

For starters, incinerators require a continual stream of waste (at least 100,000 tonnes per annum) in order to operate. This “hungry mouth to feed” not only disincentivises waste reduction, it can also cannibalise recyclable materials, undermining efforts to achieve recycling targets intended to accelerate the circular economy transition.

Burning waste also generates “severe carbon emissions”, impeding climate targets. Waste’s calorific value mostly comes from synthetic materials like plastic. Landfilling these items sequesters their embodied carbon. But when burned, the carbon is released into the atmosphere ( along with the creation of toxic, persistent contaminants, from PFAS to dioxins ), at a higher rate than fossil fuels per unit of power generated.

Recently, an expert report examining potential waste-to-energy implications in New Zealand debunked the notion that incineration is green, renewable or climate-friendly. Instead, waste incinerators would undermine New Zealand’s climate obligations, and displace electricity otherwise generated via renewables. Furthermore, investing in incineration would bypass the “abundant” employment opportunities provided by reuse and recycling activities.

New Zealand waste-to-energy proponents frequently parrot a defeatist argument that extracting some energy from waste is better than landfilling it straight away. It’s frustrating when waste conversations begin with presuming waste’s inevitability, and end with a battle over “what is the ‘least bad’ disposal technology, landfill or waste-to-energy?”

Like the question that creates the answer “recycling”, this is another “wrong” question that distracts from the pressing problem that both our current demand on the Earth’s resources and our waste generation are existentially unsustainable.

We must transition to a low-waste, circular society. In the meantime, New Zealand’s excess rubbish can be landfilled. While that’s unpleasant to write and probably also to read, landfills are a suitable transitional technology for moving towards zero waste. Unlike the hungry mouth of the incinerator, there’s no “minimum” quantity of waste to feed a landfill; you can put less and less in over time (which should be incentivised through an ever-increasing landfill levy). This frees us up to direct our creative energies upstream, towards turning off the tap, rather than continually mopping up the mess.