Green Glass Revolution - German Company Schott's Big Leap with Hydrogen Energy

The Mainz-based company Schott has for the first time manufactured optical glass with 100 percent hydrogen Alexander Sell Fotografie/SCHOTT

The Mainz-based specialty glass manufacturer Schott has for the first time tested glass smelting on a large scale using 100 percent hydrogen as an energy source. After previous tests with various amounts of hydrogen on a laboratory scale, implementation on an industrial scale has now taken place at the headquarters in Mainz, the company announced on Tuesday. For the first time, optical glass was melted without the traditional energy source of natural gas.

The quality of the resulting glass is now being tested. If it meets the product requirements, it will go to the customers. However, according to the company, there is still a way to go before this new technology can become standard. Further long-term tests and a continuous supply of hydrogen via a pipeline are required for a permanent switch. For the large-scale experiment that lasted over three days, Schott had to fully fill the hydrogen tank located on the company premises in Mainz three times.

Only one thing is missing

For the test in the large vat, what is known as grey hydrogen was used, just like in previous experiments on a laboratory scale. Grey hydrogen releases CO into the atmosphere during its production. Schott CEO Frank Heinricht said, “This is sufficient for our experiments, but we urgently need green energy for climate protection.”

Manufacturing specialty glass in melting vats requires temperatures of up to 3000 degrees Fahrenheit. Controlled, stable smelting processes are also necessary so that, for example, no tiny bubbles form that would render the glass unusable.

On the path to climate neutrality by 2030, Schott is relying on various energy sources. A pilot project with a first electric melting vat, which is to be set up at the site in Mitterteich, Bavaria, is also underway.