the TU Ilmenau and partner organizations are making glass production in Thuringia more environmentally friendly. The ZO.RRO 2 project aims to switch glass production from climate-damaging gas to renewable energy sources while increasing economic efficiency. Read how the decarbonization of the glass industry in Germany is being driven forward and what impact this could have on other industrial sectors

ZO.RRO 2: TU Ilmenau wants to make glass production climate-friendly

In a large-scale research project led by TU Ilmenau, glass production in Thuringia is to be made more climate-friendly. Together with research institutions, energy associations and industrial companies, scientists from the university are working on converting glass production from climate-damaging gas to regenerative energy sources, thus making it more sustainable and economical. The three-year ZO.RRO 2 project is being funded by the German Federal Ministry of Economics and Climate Protection with just under 2.9 million euros, of which TU Ilmenau will receive a good 1.3 million euros.


In view of the climate crisis, decarbonization of the economy, especially the energy industry, is the order of the day. Production processes that pollute the atmosphere with the climate-emittingädioxid must be converted to climate-friendly methods.To reduce the emission of greenhouse gases into the atmosphereäharmful energy sources such as gas, Öcoal should be replaced by low-carbon renewable energy sources.äsuch as wind and solar power.

Currently, the glass industry in Germany uses 90 percent gas and only 10 percent electricity to melt glass. In Thuringia, where the glass industry is a major industry, only one of 41 glass furnaces is currently heated by electricity. To decarbonize its production and operate more economically, Thüringische Wiegand-Glashüttenwerke GmbH, one of Germany's largest manufacturers of container glass, is in the process of converting its production to all-electric furnaces heated by renewable energy sources such as wind and sun.

The ZO.RRO 2 ("Zero Carbon Cross Energy System for Glass Industry") research project is paving the way for the Wiegand glassworks to make the switch and make their electric power supply sustainable and economical. But operating all-electric furnaces for production volumes of more than 150 tons per day is not easy: If the furnaces are not consistently heated in a fail-safe manner, not only will the glass melt they contain be destroyed, but they themselves could become unusable. Since solar and wind energy is not constantly available, their operation is therefore not without problems. Moreover, because plants cannot generate all the electricity needed for glass production themselves on their factory premises, the framework conditions must also be right for effective decarbonization: At the production sites, the energy supply must be reliable and renewable energy must be available steadily and in sufficient quantities, and at competitive energy prices. The ZO.RRO-2 project will also develop solutions for this.

But it is not only glass production itself, for which the smelters require most of the energy, that could be operated in a more climate-friendly and economical way: Pre-processing steps in glass processing, such as mixing, crushing and blending the glass, and post-processing, shaping, cooling and packaging, could also be powered by electricity from renewable energy sources - also a ZO.RRO 2. objective.

ZO.RRO 2 not only aims to make glass production more climate-friendly, the project has the industry as a whole in mind. Using the example of the glass industry in Thuringia, the scientists want to find out whether the findings can be transferred to other energy-intensive industries, i.e. whether industrial production processes in general can be decarbonized via a more efficient energy supply. In addition to environmental protection, the researchers are also looking at economic aspects of industry: They want to find out whether converting the German power grid from alternating current to direct current would increase the energy efficiency of the supply to energy-intensive industry and thus make production more economical.

Partner of the research project "Zero Carbon Cross Energy System for Glass Industry (ZO.RRO 2)"

Sponsored partners

  • TU Ilmenau (consortium leader)
  • Fraunhofer IOSB-AST - Applied Systems Technology Division
  • IfE GmbH - Engineering Office for Energy Management
  • KoCoS Measurement Technology AG
  • TEAG Thuringian Energy Ltd.
  • TEN Thuringian Energy Networks GmbH and Co KG
  • TMZ Thuringian Measuring and Metering Service GmbH
  • Wiegand Glassworks GmbH

Associated partners:

  • 50Hertz Transmission GmbH
  • HM Heizkörper GmbH Heating Technology


Prof. Dr. Dirk Westermann

Head of Electrical Power Supply
Director Thuringian Energy Research Institute

+49 3677 69-2838