We Live Sustainability: Plastic Vs. Glass – An Inventory
When it comes to plastics, many of us sound alarm bells. Polluted beaches littered with plastic bags or trash cans crammed with coffee cups are just two images that come to mind. We are now trimmed to pay attention to the issue of plastic. Plastic waste is a global problem and will continue to be a great challenge for us in the future. More and more companies are aware of this and are looking for alternatives for the packaging of their products. In addition to plastic, many products are now packaged and sold in glass containers. But is this shift from plastic to glass packaging a necessary step, or are we looking at the plastic problem too one-sidedly? An inventory.
Disposable glass is no more environmentally friendly than disposable PET
When considering whether to use glass or plastic containers, the material is initially less important than the distinction between disposable and reusable containers. In general: reusable ones are ecologically cheaper than disposable ones, regardless of whether it is glass or PET containers. The size of the container is also crucial. The larger the packaging, the lower the CO2 emissions per/kg of product. So far, so good. If you look at the situation with single-use packaging, it becomes more complex. When it comes to disposable packaging, many would only use glass bottles. Disposable PET containers? Better not! Unfortunately, it is not that easy. Glass is not automatically more environmentally friendly than PET containers. This can be justified with the help of the so-called life cycle assessment. Here, the environmental impact is measured from the manufacture of the packaging to the transport of the final product. In the case of glass and plastic containers, three factors play a decisive role:
# 1 Energy expenditure for production
Glass is a material that consumes a lot of energy during production to melt raw materials. Glass is made from inexhaustible raw materials like quartz sand, but it requires a very high degree of melting of around 1,650 degrees Celsius. The raw materials are melted in container glass melting tanks that are heated with crude oil and natural gas. Although almost 90% of glass containers are recycled in Germany, the associated CO2 emissions during the melting process contribute significantly to the poor ecological balance of single-use glass containers.
PET containers, on the other hand, require significantly less energy and, as many still believe, contain neither biphenyl A nor other plasticizers. However, the effects on the weather cannot be ruled out outright, especially with smaller packages. PET is a plastic from the polyester family and, therefore, requires oil for its production. Around 1 per cent of European oil, consumption is currently converted to PET. However, the degree of melting during manufacturing is only 250 degrees Celsius.
# 2 Packaging Weight
Plastic packaging is generally much lighter than glass packaging and therefore uses less oil when transported by truck. In return, this means that less CO2 is emitted. Therefore, the weight of the glass container is, a disadvantage, especially in the case of longer transport routes. This means that a 0.5 l PET bottle consumes on average around 140 g of CO2eq / kg of product. A 0.5 l glass bottle, on the other hand, consumes around 550 g of CO2eq / kg of product.
# 3 The material properties of glass and plastic
The material properties of glass and plastic lead to different reuse options. Glass is very easy to recycle, and almost everything can be reused for the production of new glass. In the case of PET containers, 50% of the recovered material is used to manufacture new containers. The other half is further processed and finds new uses in the textile fibre industry. Ultimately, PET packaging cannot be 100% recycled, but it stands out for its resistance to breakage when consumed.
Glass or plastic? The individual case decides
The question of the most environmentally sensitive packaging cannot be answered so easily in all areas. It is like everything in life; there is not only black or white because the individual case is decisive. The most important thing is that you, as a company, not only get on the train but verify and weigh all the relevant factors before deciding on packaging material. Whether glass or plastic ultimately makes more sense depends on many parameters: the manufacture of the material, the product itself, the transport route of the product, the use of the product, the legal requirements of the respective country and industry, to name just a few. The bottom line is that both have their advantages and both have their disadvantages.
In the next part of our new series, “We live sustainability“, we will tell you why we finally decided on non-returnable PET containers and what it has to do with the manufacturing process of our products. Every month we tackle one facet of the great issue of sustainability. We’ll tell you why we do certain things, how we do them, and how we can make the world a little greener with glitter and rock’n’roll.
Please read our blog on Environmentally Friendly Frozen Food Packaging: New Options for Producers
