How can green hydrogen be used in the best possible way as fuel in the glass manufacturing industry? The Federal Association of the German Glass Industry (BV Glas) is examining this question in its HyGlass project in collaboration with the Gas- und Wärme-Institut (GWI) (Gas and Heating Institute) in Essen. A reduction in CO2 emissions of up to 3.3 million tonnes could be achieved by switching from fossil fuels to hydrogen.

Glass manufacturing is one of the most energy-intensive industries due to its high heat requirement – especially for the melting process. More than 70 per cent of this energy is currently supplied by fossil fuels such as natural gas, and process-related CO2 emissions are also released while melting the raw materials. Up to 80 per cent of the overall emissions are energy related. By using green hydrogen – i.e. hydrogen produced from renewable energy – the proportion of emissions attributed to these processes would be avoided.

"The transformation of industry is also central to our business location during and after the Corona pandemic. Climate protection and innovative future technologies must be brought together to achieve the Paris climate protection goals and secure long-term competitiveness."

Prof. Dr Andreas Pinkwart, NRW Minister of Economics

Innovation: switching to green fuel

The use of hydrogen as fuel for industry is by no means a technical standard yet, so the effects on the highly sensitive glass manufacture melting process, product quality and harmful emissions still need to be investigated. The project is studying both the addition of increasing percentages of hydrogen to natural gas and the use of pure hydrogen as a fuel. Various experiments are being carried out in this context at a high-temperature furnace at the GWI. In addition, the researchers are investigating the potential of hydrogen for the glass manufacturing industry in NRW by means of extensive process simulations and production site analyses.


“Green gases are becoming increasingly important and safeguard the role gas plays in the context of the energy transition. Hydrogen will come to play a dominant role. Research and innovation are essential for future sustainability.”

Dr Anne Giese, Head of the Department of Industrial and Combustion Technology at GWI

Efficiency: technology that can be implemented in a timely manner

Switching the plants to electricity is an option, but appropriate technology for the required size of the systems is not yet available on the market. Adding hydrogen to natural gas to produce fuel for the furnaces is an economically plausible alternative that could be implemented in a timely manner. Investigating the technical feasibility of this approach is a basic prerequisite, however, for its subsequent integration and for plant safety in industry.

“This project for climate-neutral production is an important step towards exploring new avenues in glass manufacturing and helping to achieve the goal of a climate-neutral transformation of the economy in the long term.”

Dr Johann Overath, CEO of the Bundesverband Glasindustrie e.V. (Federal Association of the German Glass Industry)


potential reduction in CO2 emissions

Further links and downloads
Prozesskette der Glasherstellung

Glass production process © BV Glas

Schema Hochtemperaturversuchsofen

Diagram of a prototype high temperature furnace © GWI

CO-Isosurface (links) und Flamme (rechts) einer U-Flammenwanne

CO iso-surface (left) and flame (right) of an end-fired furnace © GWI

Stromlinien in einer Querbrennerwanne

Flow lines in a cross-fired furnace © GWI

Infrastruktur Hochtemperaturofen

Infrastructure of a high temperature furnace © GWI

numerische und experimentelle Untersuchung von Glasschmelzwannen

Flame pattern of a high temperature furnace © GWI

Flammenbild Hochtemperaturofen

Numerical and experimental studies of glass melting furnaces © GWI

Effect: basis for industrial application

The project is laying the foundations for using hydrogen in industrial plants soon. Even in a predominantly climate-neutral industrial sector in the future, glass will continue to be an important raw material. The potential for climate protection to be expected as a result of the widespread use of hydrogen for glass manufacture is therefore enormous. By replacing natural gas with hydrogen in the melting process, a reduction in CO2 emissions of around 3.3 million tonnes could be achieved across Germany as a whole.

Your Contact

Dr. Johann Overath

CEO of the Bundesverband Glasindustrie e.V.

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Dr. Anne Giese

Head of the Department of Industrial and Combustion Technology at GWI

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