The Benefits of Recycled Glass

August 9, 2022

Today's blog is authored by NERC summer intern Joseph Dolan.

For the first time in my life, I am attending summer courses. I am going to complete a Master's degree in public policy at the University of Massachusetts Amherst this year, with one of my personal interests being environmental policy. Since I was required to get a summer internship for my academic program, I approached the Northeast Recycling Council in Brattleboro, Vermont for an internship position. I am pleased to work for such an organization since I believe in noble causes, which considering my interest in environmental policy overlaps quite well with their focus on recycling.

After the process of setting up the internship was taken care of, I was asked to help out with blogs. Originally, I was asked to find potential blogs, though I also offered to write one for them during my summer internship. After my offer was accepted, I contemplated what to write about for my first blog ever. I reflected on my reason for taking this internship, beyond the academic requirements. I considered my interest in the environment, especially recycling-related topics. I came back to an article I found about the recycling of glass, a material that is endlessly recyclable. A link to the article can be found here.

The article states that glass could be recycled more, yet is not. But this is not the result of technical limitations or resistance from industry. In fact, glass recycling rates are significantly higher in Europe, where it is around 90% in countries like Switzerland and Germany, compared to around 33% in the United States. Glass recycling’s dilemma in the United States largely comes down to two key issues: the sufficient availability of quality cullet, and the economic ramifications of glass-making.

Glass manufacturers agree that recycling glass is beneficial for their own interests.  In fact, for every 10% of cullet included in their mixture, the energy needed to sustain sufficiently high temperatures to create molten glass goes down by nearly 3%. By reducing the amount of heat needed to create new glass, the lifespan of furnaces expands, in addition to lowering operating costs and decreasing the price of glass products. Another benefit of recycling glass is more directly related to the environment. For every 10% of glassmaking mix substituted with cullet, emissions of the greenhouse gas CO₂ are cut by 5%. The potential scale of recycling benefits is quite significant too, given that the United States sees 10 million metric tons of glass disposed of annually.

The significant difference in recycling rates in the United States as compared to Europe has several reasons.  Among them, legislation regarding recycling tends to be handled at the state level, whereas in Europe it is handled at the national or federal levels, eliminating the potential for inconsistencies.  Also, recycling is the cultural norm in Europe, with it being in practice for years, and children being taught about it at school and learning further still at home. By contrast, the education system in the United States tends to focus on teaching to the test, and recycling is not a subject of standardized academic testing. That said, I agreed with the article`s suggestion that it should be.

However, the simplest explanation is the difference between the United States and Europe is in how they recycle, with America being relatively inefficient. The primary method of recycling in most American municipalities is single-stream curbside collection. Single-stream means that people put not just glass in the recycling bin, but also steel and aluminum products, cardboard, and plastic, and even garbage that they think can be recycled. As a result, this requires a complicated process to sort out the glass and other materials manufacturers are not interested in, and willing to pay for, from the additional clutter. Multi-stream and source-separated recycling avoids this complexity in the processing by putting glass in glass-only recycling bins, separating glass from other materials. However, this process requires a significant amount of consumer education than single-stream recycling. Yet the benefits are clear, the glass collected from multi-stream or source-separated recycling is much cleaner and the cullet can go straight to processors to make the glass furnace ready for manufacturers without going to a materials recovery facility. For example, around 40% of glass from single-stream recycling ends up recycled into new products, compared to around 90% of glass recycled in glass-only collection systems.

Overall, I personally enjoyed reading this article and I am glad that I stumbled across it. The article was written in a clear manner and presented the details clearly, which is exactly the kind of approach needed to solve complicated problems.  This is especially true with the constantly shifting nature of politics, and the complications of differing rules by the various states, instead of a solid national policy across the whole country.

I found this intriguing since I always believed in promoting environmentally friendly behaviors, recycling included, and a more efficient way to recycle that requires more consumer knowledge seems reasonable in the contemporary knowledge economy. I can only hope that governments will promote an option for cheaper, eco-friendly glass production, and listen to the people whom they represent.