In the age of single-use plastics, glass has long been touted as a more sustainable packaging option for eco-conscious people like you.
A material which origins date back thousands of years ago, glass is widely believed to be endlessly recyclable, never losing its quality and purity throughout each new use.
When faced with the choice of either using plastic or glass, the latter is the clear winner for reducing waste.
Figures show that only as little as 9% of plastic is actually recycled worldwide, while glass is 100% recyclable and able to go back to its original form every time.
If we also consider the prevalence of hidden microplastics in our everyday life, the environmental pros of a material like glass become even clearer.
Still, the fact that using glass packaging is a better environmental choice than using plastic packaging doesn’t necessarily make your mason jar the be-all and end-all of sustainability.
So, is glass sustainable? Here we answer the most common questions surrounding glass production and glass recycling, so you can make a conscious and informed choice with every new bottle!
How is glass sustainable?
First things first, let’s look at what exactly makes glass a sustainable packaging option.
As we just mentioned, the biggest eco-friendly credential of glass is its infinite recycling potential – the material can be recycled over and over again.
Even better, recycled glass needs a much lower temperature to melt than virgin glass, meaning that recycling glass can save a whole lot of energy during production. This is the same for other infinitely recyclable materials such as stainless steel.
On top of that, glass is also the perfect material for long-term reuse. Glass bottles and jars are strong, durable, and incredibly easy to clean and sterilise. This makes it a great option if you’re looking to go green at home.
When considering virgin glass, however, the question of ‘is glass sustainable’ becomes a little more complicated to answer.
Is making glass bad for the environment?
The tricky part of this debate mostly comes down to virgin glass production and its transportation process.
Just like our ancestors used to make glass thousands of years ago, today’s glass production process still involves the use of sand — a natural material, sure, but also a finite resource.
In fact, sand is the world’s second-most used natural resource (water is the first one).
From windows to water bottles and kitchen essentials, glass is a common material used in our daily lives. This means the world’s reserve of sand and gravel is starting to shrink, slowly but surely.
Modern glass production uses a lot less sand than what the traditional method did. Nowadays, sand is mixed with recycled glass, limestone and soda ash before being melted in a furnace at a whopping 1700°C.
This process is definitely where the biggest environmental impact of glass comes from.
Emissions from virgin glass production contribute to industrial pollution and waterway pollution, just as melting the ingredients at such high temperatures contributes to intense energy use.
Finally, transporting glass does come at a higher environmental cost than transporting other materials. This is because it is considerably heavier and more fragile that the likes of plastic, requiring more fossil fuels to move and more waste due to the high possibility of breakage.
The emissions from transportation always need to be factored in when considering the sustainability of a product.
What about recycled glass?
With these considerations on virgin glass out of the way, let’s focus a bit more on the positives of glass – all of which come from recycling the material.
As a whole, producing recycled glass has been found to reduce related air pollution by 20% and related water pollution by a whopping 50%.
Compared to making virgin glass, recycling glass can save upwards of 20% more energy. When we consider that glass is so widely recycled all across the world, it’s easy to see how much more sustainable this material can be compared to plastic products and virgin glass.
Now, the glass recycling life cycle does have some problematic aspects as well.
There’s always the possibility of bottles and jars breaking during the transportation process, and coloured glass can only be recycled with materials of similar colour. This is because mixing glass colours decreases the quality of the recycled product.
But while recycled glass is not quite the perfect solution to your low-waste problems, it’s still a much better option than most alternatives due to its unparalleled reuse potential.
So, rather than sending your recycled glass packaging to the recycling bin, the most eco-friendly way forward is to keep reusing what you have as much as possible — not a tall order when glass is so sturdy, safe, and impermeable!
Is glass more sustainable than plastic?
Now, we come to the burning question most people will be wondering about when asking is glass sustainable: The plastic vs glass debate.
If we first consider the costly production process of virgin glass and compare it to virgin plastic, glass still comes out on top as the more eco-friendly option, even if it’d be a stretch to call it sustainable.
When both glass-making and glass transportation are considered, the glass life cycle actually contributes more to greenhouse emissions than plastic because of its weight and higher production costs.
The weight of a glass bottle alone makes it a less sustainable option than a plastic bottle. On top of that, both materials are not biodegradable.
However, when we consider the fact that glass is endlessly recyclable and that it doesn’t leach chemicals and microplastics as it gets recycled and reused, recycled glass is definitely more sustainable than recycled plastic.
Plastic never truly breaks down, and as it keeps getting recycled (or more aptly, down-cycled) its quality decreases until all that’s left is unrecyclable waste.
Taking all that we know about plastic production and recycling into consideration, the somewhat problematic glass is still the clear sustainability winner.
So, is glass a sustainable material?
While the concept of an eco-conscious consumer has long been associated with rows of mason jars, the production and transportation process needed to bring the material into our homes is clearly far from 100% sustainable.
Reusing recycled glass as much as possible, however, will go a long way to offset the emissions and energy consumption associated with virgin glass production – as long as you’re careful not to break it in the process!
For me this makes glass one of the more sustainable materials when can use in and around our home. And it’s still certainly a better option that using plastics.
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Ben is the Creator and Editor of Tiny Eco Home Life. I write and publish information about more sustainable, environmentally friendly living in and around the home.
Alongside this website, I love spending time in the natural world, living a simple life and spending time with my young family (Murphy the dog!) I round up my thoughts and recent blogs on the Eco Life Newsletter.