A UK study found that separating plastics in household waste for recycling was a better environmental option than incineration in a waste-to-energy facility.[1] Nevertheless, if contaminated and mixed plastic cannot be recycled into high quality recyclate, it remains an open question as to whether it should be landfilled or incinerated in a carefully controlled environment with energy capture (also called thermal valorisation). In line with the waste hierarchy, LCA studies indicate that landfilling of waste is generally the worst end-of-life management option. However, it could be argued that landfilling represents a way of sequestering the carbon in the plastic; alternatively, this can be regarded as unsustainable because it passes the problem of plastic waste management on to future generations.

There are no publicly available LCAs assessing whether landfill or incineration with energy capture is a better environmental option for Aotearoa New Zealand. Such a study would be needed to better understand the relative environmental performance of each option in our local context – particularly since the results would be influenced by the transportation requirements between points of waste generation and incineration plants or landfills.

 

There are no publicly available LCAs assessing whether landfill or incineration with energy capture is a better environmental option for Aotearoa New Zealand

 

The conclusions may also change depending on new materials and new technology. Right now, we would have to factor in that the economics of incineration plants would probably mean that only one or two plants would be feasible around the country and therefore there would be emissions related to transport. In the future, if smaller scale plants were economic that would change the outcomes, as would an electric vehicle fleet powered by renewable energy. Alternatively, there may be an increase in biodegradable or compostable plastics that enter landfill, and outcomes of the analysis may change, particularly if all waste was disposed to modern landfills with methane capture.

References

[1] Burnley and Coleman (2018)

Explore more case studies from Rethinking Plastics

Sustainability through connection, learning and action

With a kaupapa of creating a healthy, peaceful, more sustainable world, Toimata Foundation supports inter-generational learning and action by running two main programmes in schools and communities:…

Reducing the carbon footprint of plastics by using recycled plastic

In a study of the carbon footprint of projected global plastic use between 2015 and 2050, Zheng and Suh modelled a theoretical situation of 100% recycling of plastic in 2050, and found it had a 25%…

A reusable system to replace single-use cups

Globelet offers a reusable cup system for festivals and other events. The cups are made from recycled polypropylene (#5) and manufactured onshore. Globelet provides the following statistics on their…

How big is the plastic clothing problem for Aotearoa New Zealand?

Some plastic articles of clothing are captured in the ‘Plastics and articles thereof’ harmonised trade codes in import data from Statistics NZ, but this does not account for all synthetic fibres im…

A business enabling people to rethink their use of plastic

Ecostore is an exemplar of how a business can take transformative action to rethink how we use plastics and inspire system-wide change. To enable people to reduce their use of non-renewable single-…

New Zealand Post’s quest for an alternative to plastic

The driver: New Zealand Post wants a more sustainable, environmentally friendly alternative to their existing plastic mailers (e.g. courier bags, pre-paid postage bags). New Zealand Post has also…

Para Kore – helping people reduce their waste

Para Kore is a Māori organisation that provides mentoring and support for marae, kōhanga reo, kura, community organisations, iwi, tertiary, commercial sector, events and Māori communities to reduce…

Plastic Bag Free Raglan, Pēke Kirihou Kore Whāingaroa

In October 2018, Whāingaroa Raglan won the Keep New Zealand Beautiful ‘Community Environmental Initiative Award’. The kōrero behind the Award was a story of what happened when a whole community wor…

Controlled plastic decomposition

Plastics are made by joining monomers together to form long flexible chains in a process known as polymerisation. The strength of the bonds formed between monomers is what makes the plastics persis…

Recyclable shoes

As part of its recent pledge to use only recycled plastics by 2024, Adidas revealed a new sneaker made from 100% recyclable materials. Driven by a connection to environmental organisation Parley for…