The main source of carbon dioxide emissions in the production of glass is related to the energy consumption required for the melting of the raw materials. While 100% electric furnaces do exist, there are currently hardly any glassmakers using them and they need to be powered by fully renewable electricity to claim carbon neutrality.

No carbon dioxide emission

To deal with that issue, Steklarna Hrastnik has used so-called “green” hydrogen as a sustainable fuel to melt glass for a first batch production of the “carbon free bottles”.

Indeed, hydrogen can be produced in several ways, one being when an electric current splits water into oxygen and hydrogen. To be fully sustainable and carbon neutral, this process, called electrolysis, requires the electricity to come from a renewable source of energy. In such a case, hydrogen is considered as being “green”.

For the production of their first batch of carbon free bottles, Hrastnik1860 has used green hydrogen produced by electrolysis thanks to solar cells. The main raw material was made from external cullet collected from waste recycled glass. "Oxygen and hydrogen were used as fuel. The only emission produced in the glass making process was water vapour instead of carbon dioxide," said the company in a statement.

Scaling up production to industrial levels?

Of course, the cost of such a process is not trivial, since the manufacture of "green" hydrogen is relatively expensive compared to natural gas, for example. Steklarna Hrastnik, however, said they are ready to invest in industrial production capacity for brands that would be ready to make exceptional efforts in terms of sustainability and decarbonisation.

To date, the company has a capacity to melt 200 kilograms of carbon free and 100% PCR glass,” said Peter Čas, CEO of Hrastnik1860.

For the industrial scale test, which will be done in 2022, the company will source hydrogen from a third party producer but “in the future our aim is to produce green hydrogen as our own fuel for industrial glass melting,” added Čas. Steklarna Hrastnik believes to be able to produce their own hydrogen within two to three years.

We want to be at the forefront of the glass industry when it comes to sustainability,” claimed Čas.

Actually, after years focusing on reducing gas emissions, a technological breakthrough is now required to reach the carbon neutrality goal by 2050 set by EU regulations.

Hrastnik1860 plans to decrease their carbon footprint by more than 25% by 2025 by replacing a third of their fossil fuel consumption by green energy, and by increasing energy efficiency by 10%.

In the longer run, the company’s ambition is to reduce their carbon footprint by more than 40% by 2030 and going neutral by 2050.