There’s lots we can do to get around the limitations of New Zealand’s glass recycling system and to harness the environmental benefits of glass packaging.
Glass, there’s no other form of packaging that people get quite so nostalgic about. With plastic getting such a bad rap these days, environmentally-conscious consumers are increasingly hunting out products and goods packaged in other materials, and glass is a favourite. But is the benevolence of glass really what it seems, or does this miracle material have some environmental limitations? From a sustainability perspective, how well do we use our glass resource in New Zealand to get the most out of its benefits rather than amplifying its limitations? What can you do to get the best outcome for your household’s glass recycling in your district or region? How can we encourage central government, local government and businesses to step things up?
This three-part post explains:
As a form of packaging, glass shares some of the benefits that many consumers and businesses like about plastic: it provides a high barrier that protects food; it can withstand liquid/wet products; and it’s see-through. In some or all these cases, other alternatives, like paper, fall short. Glass packaging also has some obvious environmental advantages over plastic packaging:
In recent years, the question of glass vs plastic packaging has increased as waste issues have skyrocketed to the top of people’s agendas. However, the growing war on waste has been very focused on plastic, particularly the impact plastic has at the end of its life (once it’s thrown out/leaked into the environment). When viewed from this perspective, the fact that glass breaks down safely and is relatively non-toxic is a deal breaker in favour of glass packaging for most people.
However, the problem with focusing on the end-of-life environmental footprint of our waste streams is that it only gives us part of the picture. In truth, packaging starts impacting the environment well before it’s chucked out – it starts from the extraction of raw materials, and continues through to packaging’s manufacture, transportation, use and disposal – looking at all these phases is referred to as a ‘life-cycle’ perspective.
A ‘life-cycle’ view of packaging reveals that glass has some clear environmental drawbacks. Producing new glass is far more energy intensive than producing new plastic, and glass is much heavier to transport than plastic, giving it a higher carbon footprint. So, in a world of single-use disposables, choosing glass over plastic isn’t necessarily as flash as we might presume because as a single-use item, glass has much greater global warming potential.
Now this doesn’t mean that we give up on glass (in our view, rethinking our prolific use of plastic packaging is non-negotiable, and glass is a key part of this rethink). However, we need to confront the reality of glass’ potentially negative environmental impact in order to promote ways of using it sustainably. In this case, understanding that the manufacture of glass impacts the environment tells us that glass packaging shouldn’t ever be treated as single-use or disposable – it just takes too much energy to justify only using it once.
And this is where we need to look to glass’ benefits to help us out. Glass’ infinite reusability and recyclability are the key to offsetting the global warming potential of its original manufacture. For starters, making glass bottles/jars from recycled glass emits much less carbon than using brand new glass – a 5% reduction in carbon emissions for every 10% of recycled glass used – so getting recycled glass into our glass production instantly brings down the carbon footprint of glass packaging
Recycling still uses quite a bit of energy though, which is why glass’ power to be reused is so exciting – all you need to do is take back and sterilise the container and then it’s good for a refill! Did you know that if a glass beverage bottle is reused roughly three times, its carbon footprint equalises with that of a single-use plastic bottle? And we can totally strive for more than 3 goes around; in well-functioning glass reuse and refill systems, a single glass bottle can be reused 20-30 times! (see pages 19 and 22 of O-I Sustainability report).
We want to stress that it’s very difficult (and controversial!) to assess exactly how many times a glass container must be recycled or reused before its energy efficiency breaks even with a plastic one (there are huge variables at play between countries, distances a product or packaging might travel, the particular food or drink being packaged, whether the plastic bottle/containers get effectively recycled etc.). However, what is not in doubt is that because glass requires so much energy to manufacture first off, if we want to make it truly environmentally worthwhile to use glass packaging more and plastic packaging less (which we do want to do because glass has a much lower end-of-life impact), then a reliable system for glass recycling and reuse is essential.
Now we’ve established that, it’s time for Part 2 of this post, which deals with the problems of glass reuse and recycling in New Zealand.
So here lies the issue in New Zealand: we frequently miss opportunities to commercially reuse glass, and we squander the benefits of glass through systems and policies that often lead to it being down-cycled or treated as a single-use item. Although many households do well at putting their glass out for recycling, unfortunately this isn’t the end of the story. Too much of our glass is effectively (or actually) landfilled rather than recycled, thanks to poor recycling systems and infrastructure, low recycling rates, and a lack of product stewardship schemes that require businesses to take responsibility for their packaging.
What makes the conversation even more complicated in New Zealand is that every district or region manages glass differently and the obstacles in your region (if any) aren’t necessarily the same as another area close by. It’s important to understand the situation where you live so that you can start to suss out what’s happening with your glass and, if necessary, start working out what you can do to get the most out of glass packaging.
New Zealand has one glass recycling plant, in Auckland, run by Owens-Illinois (called O-I for short). This is the only place in New Zealand where glass bottles and containers can be turned back into glass bottles. So, when you want to work out if your region or district is effectively harnessing glass’ infinite recyclability, what you want to know is: is our glass recycling being sent to O-I?
This is a legitimate argument that we’ve certainly heard many times. Frankly, it’s an area that warrants further research as we know of no assessments of the environmental pros and cons of transporting glass for recycling from isolated and under populated parts of the South Island to Auckland. However, it is worth noting that while Auckland seems far from many parts of New Zealand, it is nevertheless an on-shore recycler. In New Zealand it’s pretty rare to have on-shore processing plants for our recycling. Most of our recycling gets shipped overseas, long distances – plastics, metals, and some paper and cardboard. We do this despite the carbon emissions. In comparison, O-I is actually pretty local!
We’re also pretty sure that most commercial recyclers are less worried about emissions from shipping glass to Auckland and more worried about transportation costs. Generally, community recyclers (who operate a social enterprise model where bottom lines are less crucial and whose core focus is waste minimisation) choose to send their glass recycling to Auckland, even long distances. For example, the community recycler Wastebusters (in Wanaka and Alexandra) subsidises the cost of shipping glass recycling to Auckland through other more profitable parts of their operation. The fact that they choose to ‘lose’ money to transport glass the distance for recycling indicates that the environmental benefit of doing so stacks up. If it didn’t, presumably they would save that cash and turn the glass into roads instead.
Ultimately, we believe that hinging the environmental viability of glass recycling on the calculation of energy emissions in the moment of transportation for recycling is too narrow to capture the overall environmental benefit of:
These are environmental outcomes that are difficult to measure without a more holistic outlook.
Here’s the bad news. The location of the plant combined with the low price O-I has been offering for glass recycling can make it logistically and financially difficult for many parts of New Zealand, especially in the South Island, to get glass recycling up to Auckland. Consequently, vast swathes of the glass that South Islanders put out to recycle never gets to Auckland and so never gets recycled back into bottles. With notable exceptions (such as Dunedin City, Ashburton, Wanaka, and pockets of the West Coast, who prove that the logistics are not insurmountable), this is the case for most kerbside glass recycling collections throughout Canterbury, Otago, Southland and parts of the West Coast (though in some of these locations, the reason for the glass not going to Auckland is compounded by other systemic boo-boos – see the section on ‘co-mingling’ below).
If it’s not being turned back into bottles, then what happens to all that glass collected for recycling? In most cases it will be stockpiled for eventual crushing and downcycling into roading material (i.e. glass-phalt/glass-crete), sandblasting or other landscaping purposes. In some places, such as Timaru, the glass is stockpiled in the hope that the price offered for glass recycling will rise (though in the meantime, some of the glass in the stockpile may still be crushed and downcycled). In other places, the glass goes straight to landfill, as has been happening with kerbside glass collection in Central Otago (and used to happen in Queenstown). In some parts of the country, such as Clutha District, the council has decided not to collect glass through kerbside recycling at all and any glass brought to the transfer station is stockpiled.
Turning glass into roads or sandblasting material may achieve councils’ goal of ‘diversion from landfill, but it certainly isn’t what most waste conscious people envisage when they put their glass bottles out for recycling. Using some glass for roading aggregate is probably all fine and good, but turning an infinitely recyclable material into roads as a matter of course is hugely disappointing; once glass is embedded in a road, you can never get it back again and you’ll need to go mine some more silica sand if you want more glass (so there goes those potential energy savings from recycling…). For this reason, we consider using glass in roads to be ‘down-cycling’ not recycling, and in fact not that different from landfilling it.
In truth, the issue of transporting glass recycling up to Auckland is not the only barrier councils and recyclers face to recycling glass properly. Possibly a bigger headache is the co-mingled recycling system that so many councils and/or their contractors have adopted for kerbside collection. A co-mingled recycling collection is one where households put ALL their recycling into the one bin, rather than collecting glass separately in its own bin. Colloquially this type of system is referred to as ‘co-mangling’.
All our recycling in one bin sounds so convenient though… why is co-mingling a problem?
Co-mingling mangles glass… Although glass is infinitely recyclable, it’s quite fussy. Any contamination of the glass with other materials can make it impossible for O-I to recycle. Also, to be recycled back into new glass bottles and containers, glass must be colour-sorted (clear, green and brown).
This is why kerbside recycling is split in two in many parts of the country, with paper, cans and plastic in one bin one week, and glass in a separate crate the next week (otherwise known as a ‘glass out’ system). This ensures that the glass does not get contaminated by other recyclables, and makes it easy to colour sort at the sorting facility.
However, over the last 10 years many councils have contracted out their waste collection and recycling systems to large businesses, often leading to the introduction of privately-operated wheelie bin systems, with the recycling wheelie bin being “co-mingled” (private businesses who run recycling for profit prefer commingling because it cuts collection costs). These commingled wheelie bins then get sent to a Material Recovery Facility (or MRF) where all the recyclables get separated out again by a machine, or by humans standing at a conveyor belt with recyclables whizzing past.
Turns out that throwing everything together and then separating it out again with machines later is not a good story for glass. Why? As Gina Dempster from Wanaka Wastebusters describes:
Imagine taking a bin of glass, smashing it up with a hammer, mixing in bits of plastic, paper, cardboard and bottle caps, and then jumping up and down on top of it.
That’s what recycling looks like after it’s all been picked up from the same bin.
Now imagine spreading that mess out and trying to separate the broken glass from all the other (often sticky and smelly) materials.
Yep, not so pretty. In fact, glass wreaks total havoc in MRF systems. For example, in Southland, Southern disAbility Enterprises, who manages the region’s recycling, has had to spend hundreds of thousands of dollars on extra staffing to extract the glass from the comingled collection and on the costs of fixing the damage caused to their conveyor belt by shards of glass running through it.
As a result of these dramas, many recyclers in co-mingled systems have sought to have glass recycling collection cease unless a better solution can be reached (like Southern disAbility Enterprises) or have actually ceased kerbside glass collection, as happened in Tauranga in March this year (though since October 2018 the Tauranga City Council has intervened and now runs a kerbside, separated glass collection system like they should have had from the get-go).
And yes, this chaotic system clearly results in the glass being thoroughly contaminated by other recyclables and makes the idea of colour sorting almost laughable. The sum total? O-I cannot accept for recycling any glass which comes from a ‘co-mingled’ collection system.
So, if you want to know what’s happening to your glass recycling, another clue is to look at your kerbside recycling collection – do you have a separate recycling bin just for glass? If you don’t and your system is co-mingled, you can bet your bottom dollar that the glass is probably not being turned back into bottles but is instead being crushed and turned into roads (there are exceptions, such as Marlborough and Hamilton City, where the glass is separated out on the kerb before it is put into the truck). This is the case for the kerbside collections of glass recycling in huge centres like Christchurch and Auckland.
Yep, you read right. Glass collected at kerbside in Christchurch and Auckland is co-mangled. That’s a lot of lost glass. While all of Christchurch’s kerbside glass recycling is turned into roading aggregate thanks to commingling, Auckland’s situation is less dire. Visy, the Australian company that manages the city’s MRF retrospectively installed a flash “optical sorter” to colour sort smashed and commingled glass (after they got bad press for their massive glass stockpile, dubbed “Mount Visy”, which started to accumulate several years ago because of commingling). The optical sorter has increased the amount of glass they can salvage and send to O-I, but it’s never going to be as effective as a glass out system (it’s hard to find any clear info on the precise glass rejection rates from Visy, some have suggested as high as 25%, but it would be great to have a clear figure), and the tech is pretty expensive and flash, not the kind of thing that MRFs in other parts of the country are likely to invest in.
What’s especially ridiculous about this situation is that, while many South Island communities struggle to send their glass the huge distance to the glass recycler in Auckland, too much of the glass collected on the kerb in Auckland, at O-I’s doorstep, can’t go to O-I because of the council’s decision to contract a recycling service that operates a co-mingled system. Furthermore, the amount of time and investment that needs to go into righting the wrong of commingling after the fact (presuming such righting is even attempted) could simply be avoided if councils were to operate a separate glass collection system.
In parts of New Zealand where glass recycling is such a flop, businesses should be encouraged to allow for return, refill and reuse of their glass packaging. And given that the energy and emissions savings from reusing glass exceed recycling, we should really opt for return, refill and reuse systems whenever we can, regardless of the recycling situation. As a 1997 Ministry for the Environment publication The State of New Zealand’s Environment noted when remarking on New Zealand’s packaging waste:
“…packaging waste would be even less if the industry had not replaced reuseable packaging, such as glass bottles, with disposable containers, such as cardboard cartons, aluminium cans and plastic bottles (McLachlan, 1993). Although many of the disposable containers are recycled, it takes much more energy to recycle and reconstitute a container than it does to wash it…”
People frequently ask us, nostalgically, “why did we stop using reusable glass bottles for our milk”? People love the idea of reusable glass milk bottles, but in many parts of the country it’s simply not an option. The best set-up we’ve seen is in Nelson-Tasman, where local milk company Oaklands has teamed up with milk delivery company Milk & More so that people get home deliveries of milk in reusable glass bottles. A few other schemes for milk in reusable glass bottles exist around the country, such as Windy Ridge and Holy Cow in Otago, and Henderson Dairy, Go 2 Raw Milk, and Farm Fresh South in Southland. Milk vending machines where people bring their reusable glass bottles back to be refilled, self-service style, are also popping up across New Zealand.
Beyond milk, at Farmers’ Markets people who sell their preserves or other goods in glass jars are often happy to take back their jars for sterilisation and refill. For cosmetics, many small scale producers will do this too. Meanwhile, the old-school Swappa Crate system for beers is still available across the country, though its use has been eclipsed by ‘stubbies’ which people find more ‘convenient’ because they don’t have to return the bottles after (they can just be chucked out – either in the bin, or a recycling bin).
While we’ve seen an uptick in some of these refill/reuse options, most people still shop in supermarkets where refills and returns are not available. And, how many large scale bottling or canning companies do you know of in New Zealand that accept jar and bottle returns for sterilisation and refill?
Ultimately, our society and the systems within it are geared towards single-use, mostly plastic packaging, and the take, make dispose rather than closed loop/circular model. It wasn’t always this way, but it’s become so thanks to the growth of supermarkets, changes in the way beer and milk are produced and distributed, and the cheaper costs of transporting single-use plastic containers (which became important as distribution centres in smaller parts of New Zealand started closing in the 90s).
Given that many of the big players don’t want to play ball in the reuse world, getting change is difficult because it requires keen businesses to go out on a limb and often put themselves at financial risk (it’s pretty hard to be a trend setter when you are a small business swimming against the tide of the ‘way we do things’). Have a look at this article written by Glen Herud, the owner of Happy Cow Milk Co who recently explained the difficulty he found using reusable glass bottles in the conventional milk industry. This video by Re: also outlines the logistical challenges that milk businesses face to using reusable glass when the bulk of the industry prefers single-use plastic packaging.
To top it all off, New Zealand has low recycling rates, including for glass, even in parts of the country with a decent glass recycling system. In 2016 it was estimated that about 27% of New Zealand’s glass containers (or 60,000 tonnes) ended up in landfills across New Zealand. However, this figure is based on an assumed 73% glass recycling rate, but even this has been contested by waste experts as inflated, suggesting that the numbers of glass containers being landfilled or littered is even higher.
Apart from households, many hospitality businesses are still not sorting their recyclables and this means that we’ve really started to question what we order when we’re out, regardless of whether the item came from a glass or a plastic bottle. For example, we stopped ordering wine when out in Wellington, even though Wellington has a good recycling system for glass, because so many restaurants and cafes do not recycle. We also only ever order beer on tap in bars for the same reason. Again, if the glass bottles we use go straight to landfill, we’re effectively treating the bottle as a single-use item and that’s just no good for our carbon footprint.
While the previous parts of this post might seem depressing, the situation is not hopeless. We’ve focused on the problems with the current approach to glass packaging in New Zealand because we need to understand them in order to find solutions that actually address the precise problems.
Various possible solutions exist for addressing the current limitations of New Zealand’s glass recycling and reuse systems. In lieu of bigger, systemic, policy changes, here are some things that individuals and businesses can do, from tomorrow, to treat their glass better:
Don’t just automatically presume that because glass is theoretically infinitely recyclable (and because it’s not plastic) that you don’t have to think twice about it. Whether glass is recycled or not depends hugely on where you live. We go for unpackaged wherever this is available, even for goods that are traditionally packaged in glass. For example, we get beer on tap into our own bottles, we get oils and vinegars from bulk stores on tap into our own bottles (especially when the stores source these products locally and get their own dispensing drums refilled), we refill our peanut butter jar at the peanut butter dispensers at Bin Inns. We also refuse to buy things we don’t need, even if those things are packaged in glass. We always take these steps in parts of the country that don’t get their glass recycling to O-I. However, we also do this in parts of the country where glass does get recycled back into new jars and containers because as we have noted already, recycling is still a more energy intensive process than reuse systems for glass, which leads to the next point…
If you live somewhere where glass is downcycled or landfilled, glass can still be an excellent packaging option if businesses take their glass bottles and jars back for sterilisation and refill. Keep your eyes peeled for any milk companies in your local area that use reusable glass bottles, and go to Farmers’ Markets and find out who packages in glass (food or cosmetics) and accepts those jars and bottles back for sterilisation and refill! If the business or stallholder won’t do this, ask them why. If they say “don’t worry, it’s recyclable”, follow up with them about this and explain the value of reuse systems.
Most transfer stations and community recycling centres have colour sorted bins for their glass recycling. If you personally drop it off here (and delete the co-mangling middleman), it won’t be contaminated, it’ll be colour sorted, and it will more likely get to Auckland. This is the case for Central Otago (take your glass to Wastebusters Alexandra instead of using the kerbside system) and the community recyclers in Auckland. Another option is to look out for the Glass Packaging Forum bottle banks/drop-off points, as these are also returned to Auckland for recycling. HOWEVER, don’t presume that your recycling depot/transfer station/community recycling centre does send their glass to O-I – still make sure that you ask them, as they may face the issue of transportation logistics.
If you’re a retailer, explore whether you can sell more goods in bulk/on tap (such as oil, vinegar, beer, preserves, condiments etc.,). If you’re a producer, can you package your goods in glass and take those glass jars back for sterilisation and refill? The system works really well if you advertise it well (so people know it’s an option), if you provide a deposit for people who return the bottle/jar, and if you charge a little bit extra the first time people purchase the goods in a brand new bottle/jar. There are many companies, especially smaller, local producers that do this, and the smaller the geographical area of your distribution, the lower the carbon footprint because transportation distances are smaller. Apart from reducing waste and saving money, having a return/reuse system for your business’ glass receptacles promotes customer loyalty to your product and business.
There isn’t much more to say on this point, other than that, as a consumer, we would avoid establishments that don’t recycle and encourage others to as well. If we do visit non-recycling restaurants, bars or cafes, or if we aren’t sure whether the place recycles and aren’t in the mood to interrogate the poor staff, then we just don’t order any drinks other than those on tap. Basically, we’re reaching a point in New Zealand where it’s no longer socially acceptable not to recycle. So, if you run a bar, restaurant or cafe and you’re not recycling even your glass yet, it’s better to start than to risk losing business.
Beyond taking control of your own glass footprint, you can also use your new-found knowledge about glass recycling and reusing to do some informed advocacy for new systems and policies that could help New Zealand harness glass’ true potential! Here are some things we can talk to our councils and central government about:
One can only presume that the move towards co-mingled collections for recycling was implemented without adequate appreciation of the implications this would have for glass recycling in New Zealand. Either that or there were a lot of people in the decision-making process who were wilfully ignorant. Whatever it was, there’s no denying now that it’s pretty obvious we can’t achieve proper glass recycling with co-mingled glass collections (there aren’t going to be many sorting facilities in New Zealand that will fork out for the kind of optical sorting machinery used in Auckland, which is only partially effective anyway). The only viable kerbside collection system for glass is a separated one. We encourage you to advocate that your council adopts a separate, ‘glass out’ system (if they don’t already) and includes this as a requirement in tenders for future waste collection contracts. There are health and safety implications when it comes to the weight of the crates of glass and potential infrastructural/asset questions, including pick-up trucks that account for separate glass collection. These are surmountable issues; councils and recycling collectors can look to parts of the country that manage a separate glass recycling bin system to see how this could work: Wellington City and Dunedin City are some examples.
Apart from all the other benefits that a container deposit or bottle deposit scheme could bring to New Zealand, they’ve got another HUGE drawcard that is under-discussed… a bottle deposit scheme could cover the costs of transporting glass bottles from the South Island to O-I AND because it’s a drop-off system, glass bottles would be separated and colour sorted when dropped off, so there’s no risk of contamination or mangling.
Yup. That, on its own, is a deal-breaker for us in our support for bottle deposits. We encourage more people to highlight this benefit when contacting Government Ministers to call for the implementation of a bottle deposit scheme in New Zealand. If you want to know more about how you can join the call for a bottle deposit scheme in New Zealand, check out our post on this topic.
A few people in the know have suggested that a South Island glass recycler would be a game changer in the South Island. While we agree that it might well be (and that this would reduce emissions for transporting glass for recycling), the smaller population is likely to make this option financially unviable, especially in light of the existence of a co-mingled kerbside collection system in the most populous part of the South Island (Christchurch), which reduces further the numbers of bottles that could be usefully sent to a theoretical South Island plant. Perhaps if Christchurch were to implement a separate collection for glass, the economics might change. In either case, a bottle deposit scheme would be a far cheaper and faster option for sorting out transportation logistics.
Districts that have community recyclers almost always achieve better outcomes for their recycling and a heightened appreciation of waste minimisation. This has proven to be the case with glass recycling in different parts of the country (among other types of recycling). The hands-on manual sorting that community recyclers often do might be ‘slower’ or more ‘costly’ but it pays for itself in the long-term – they achieve better quality recycling (such as reduced contamination rates for glass), increased community engagement on waste, and high value jobs of meaning in small communities. We are convinced that the more community recyclers we have in New Zealand, working together across the country (as they already do so well through the Zero Waste Network), the more hope we have of achieving consistent, best practice glass recycling and reuse systems.