Why bother melting recycled glass?

At the very core of our business, one of our most important principles is sustainability.  We take it seriously at Bicycle Glass and believe that being sustainable is both good for the environment as well as sound business practice. 

To that end, the glass we use in all of our products, is 100% locally sourced post consumer recycled glass.  We say it all the time in each one of our products, and the question is: why does it matter?

First: Let's Look At How Melting Glass is Traditionally Done

Before David and Michael got together to create Bicycle Glass each one of them had a studio where they melted raw and clear only "batch" glass the traditional way.  Color was added to the glass and while the finished products were beautiful, any excess glass that had color on it became "contaminated" and we would pick out the colored bits before remelting it in our furnace so we would get clear and clean glass each time.  We would recycle some of the glass that we had used during the blowing process (maybe 20% or because much of it was "contaminated" with color).

  "Batch" glass refers to using raw materials (primarily Silica, Soda-Ash, and Limestone) that came premixed in 50 lb bags.  We would shovel this into our furnaces (80% or more) and also the 20% non-contaminated cullet as well.  After filling the furnaces, we would turn the furnaces up to 2400 degrees Fahrenheit and "cook" the glass overnight.

Melting Recycled Requires Less Energy

One of the first ways that melting glass recycled glass matters from an environmental perspective is that it requires less energy to melt. Some studies place this number at between 15 - 20%. 

Generally speaking we don't have to melt at as high of a temperature for as long which reduces the amount of energy needed to melt the glass substantially which lowers our carbon footprint per pound of glass melted significantly.

Using Locally Sourced Post-Consumer Glass Takes Less Energy to Transport

The traditional way of getting the glass batch to our door step required that miners of the raw materials (Silica, Soda-Ash and Limestone) to quarry the material (from all over the country) then ship it to the east coast to be blended to a specific formula that would work with our colors* (more on that later), and then it would be shipped to a distributor on the West coast and then finally shipped by truck back to us.

By the time that the raw material made it's way back to us, the same pound of glass had potentially gone around the country twice.  Honestly, this isn't as bad as it gets.  Today some artists are importing raw materials (blended specifically) from overseas and then transporting it inland from where it comes into port, thus increasing the carbon footprint considerably from even the above scenario.

By contrast we get locally sourced recycled glass within our own community.  The glass we use comes from our community so we can cut down the transportation added carbon footprint per pound essentially to near zero.

Melting Cullet Does Not Lose Any Weight During The Melting Process.

One thing that happens when you melt raw batch is that you lose, by weight, between 12% - 18% due to volatilisation.  As the glass gets melted, it loses weight due to the raw materials and chemicals undergoing different chemical processes and some of the weight of the product is lost. 

This means that you for the same pounds of glass product output you need to both melt more and source more glass to get the same amount of end product which both contribute to glass making's heavy carbon footprint.

We Do Not Import Color Saving Further on Our Carbon Footprint.

Earlier I mentioned color.  The reason that glass artist prefer to use clear glass is because it is a good base and allows for a wide range of colors.  Those colors all have to be compatible with the base glass and have the same coefficient of expansion.  If two glasses are not compatible and are melted together and then subsequently cooled, one will cool and shrink faster than the other one causing the piece of glass to break. 

This is why artists prefer to buy raw batch that is premixed to be able to be compatible with all these colors.  If artists did not have this consistency, many of their pieces would break.  Artists want to focus on being artists and not on scientifically engineering their glass to be compatible with German color bars.

The bars of color used to make artistic glass are imported from Germany and New Zealand, again a raw material is being imported to make a product which increases the carbon footprint further.

As far as Bicycle Glass is concerned we make three colors only (as we can, we will add more as time goes on).  Each color is made in house and we reuse 95-98% of the glass over and over again. 

So Why Isn't Everyone Doing This?

In a word.  It's difficult.  Melting and refining 100% recycled glass is hard to do, the glass isn't compatible with all the German (color bar), colors of the rainbow which makes it less desirable if you are an artist that prefers to work with a wide range of colors and, to boot, no one does this so if you have a question about anything, you'll just have to work it out yourself.

At Bicycle Glass it took us a long time to refine our glass so that it would work well for us, and oftentimes its temperamental and gives still us many headaches and for many other reasons like its workability and non-malleable state many artists would never want to work with it.  Additionally, the contamination sometimes is amazing, you wouldn't believe the stuff that people put into their recycling (light bulbs, ceramic dishes etc.) that we pull out of our furnaces.

With all that being said, making recycled glass products is one of the core components to our mission and helps us lower our footprint at Bicycle Glass which is extremely important to us.