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 signed the New Zealand Plastic Packaging Declaration, committing to using 100% reusable, recyclable or compostable packaging by 2025. 

The plan: In late 2017, New Zealand Post put out a request for information (RFI) for an alternative carrier pack material. Potential materials were assessed against value chain criteria as outlined in the Sustainable Business Council Value Chain Guide.

The contenders: A range of options were submitted by suppliers, including compostable, biodegradable, materials with recycled content and oxo-degradable. When materials were assessed, initially compostable materials looked the most promising due to a number of factors, including apparent ease of end-of-life disposal, range of manufacturers and potential cost profile. A detailed request for proposal (RFP) was issued for a compostable carrier pack in early 2018. From further investigation of compostable material use in Aotearoa New Zealand, as well as information gathered through the RFP process, it became apparent that compostable plastic may not be a better option.

The issue: There are a number of barriers to the use of compostable plastic carriers in Aotearoa New Zealand at the time of New Zealand Post’s assessment. Most commercial composting facilities will not accept compostable plastic film, and there is a lack of approved compostable adhesives and labels meaning the whole product cannot be composted (and it was unclear whether consumers could be relied on to remove the non-compostable components). There were no Aotearoa New Zealand-wide home compostable standards in use, although overseas standards were applied to some products. Leaving such packaging to mainly be composted in a home composting environment also raised concerns, including the accessibility to effective composting at home. Consumers who have no effective way to deal with compostable plastic may treat the carriers like current non-compostable packing and possibly contaminate soft plastic recycling streams. Compostable plastic requires a specific composting environment in order for it to be able to break down and fully return to nature. Without these conditions, their environmental benefits over a non-compostable product are debatable.

The decision: As part of their assessment process, a survey of 1000 New Zealanders was undertaken – 66% said they would prefer a compostable product over a traditional plastic one and thought it was better for the environment. But the lack of infrastructure and consumer awareness around the complexities of compostable plastic made the New Zealand Post team feel that to offer this product at this time would be greenwashing and not a responsible business decision.

The outcome: New Zealand Post continues to explore alternatives to current carrier packs. Shortcomings in soft plastic recycling infrastructure in New Zealand, including recent changes to the soft plastics recycling scheme, need to be addressed when considering the feasibility of alternative packaging. In light of this work, New Zealand Post has put out a set of sustainable packaging guidelines to guide the development of parcel packaging to fit the circular economy model and are keeping their website up-to-date with progress.

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