Less material and more green energy: The glass industry is becoming more sustainable

Food and beverages can be safely stored in glass packaging. Glass is solid, robust and above all inert, which means there is no reaction between the content and the packaging. It is also endlessly recyclable. However, glass is heavier than other packaging materials and the production of glass packaging requires a great deal of energy. The industry is working hard on reducing carbon emissions in all production phases.

Glass packaging is popular and the demand for it is rising. According to the Federal Association of the German Glass Industry, approx. 4.6 million tonnes of container glass were sold in 2022, resulting in 4.3 percent higher sales than in the same period of the previous year. At the same time, brand manufacturers are increasingly demanding more environmentally friendly packaging solutions. The glass packaging industry in Europe has set itself ambitious goals in this context: By 2050, the aim is to make glass production not only completely climate neutral, but also to offer packaging solutions that can be completely recycled, according to the European Container Glass Federation FEVE. For this purpose, glass melting technology in particular is to be converted to use green and renewable energies.

There have been several initiatives in the past few years in order to achieve the statutory objectives. For example, the Eco2Bottle was introduced, a climate-neutral wine bottle of the glass container manufacturer Wiegand-Glas from Upper Franconia. It is made of 93 percent recycled glass and weighs almost 20 percent less than comparable wine bottles from the Wiegand glass portfolio. Lower weight also means using less raw materials and producing lower carbon emissions during transport. The sustainable wine bottle has already been awarded several prizes and is currently also being used in other segments. For instance, the new introduction of the 0.33-litre glass bottle for Adelholzener Alpenquellen GmbH was implemented as an Eco2Bottle project.

The glass packaging manufacturer Vetropack has developed an innovative technology for manufacturing lightweight, robust and durable glass bottles and, with the lightweight glass technology Echovai, has produced the world’s first reusable bottle made of thermally hardened lightweight glass. It is not only light, but also exhibits less wear, which makes more cycles possible. In addition, this reduces the logistics expenditures and carbon emissions per bottle. 

Tempered glass per se is not a novelty, but has been used in other industries, for example in car windows, for many years. For glass packaging, however, the procedure had reached its limits, until now. The thermal treatment that finally gives the glass greater stability partially limits the possibilities of product design at first. It is true that the Echovai procedure, caused by strong heating and subsequent quick cooling of the bottles, places high demands on production. This applies both to the quality of the material and to the production process and its systems.

The development of Echovai took approximately ten years in the Vetropack centre for innovation. Over the past few years, millions of bottles were successfully sold and refilled at the Austrian pilot customer Mohrenbrauerei. Tests have confirmed the prolonged service life and durability of the Echovai bottles. The 0.33-litre reusable containers alone achieve a reduction of weight by approximately one third compared to the previously used standard bottles (300 grams) by using the Echovai solution (210 grams). At the same time, since the lightweight bottles are shorter, it is possible to stack them on pallets in six instead of the previously common five layers. This affects the logistics expenditures: the carbon emissions per bottle were reduced to a mere quarter of those of the standard 0.33-litre reusable bottle.

In Austria, Vetropack is making use of these properties to contribute to the quota of reusable packaging, which will be mandatory as of 2024. In this context, the glass manufacturer, together with relevant stakeholders like the company Brau Union, the Austrian logistics association for reusable packaging Logistikverbund Mehrweg, the breweries’ association and its members, developed a new 0.33-litre reusable bottle made of Echovai lightweight glass, which is made available to the entire national brewery business through a pool solution.

The glass manufacturer also offers customers comprehensive life cycle assessment calculations which map the entire life cycle of a glass container and which go beyond the glass itself. To do this, Vetropack not only works with real-time data from its own plants, but also takes the entire added value chain into account: primary and secondary raw materials, fastenings, labels, transport packaging and, last but not least, bottling and transport. The resulting assessment offers insights into the carbon footprint of packaging – and into any potential for optimisation.

Last year, the Federal Association of the German Glass Industry (BV Glas) presented their carbon roadmap towards climate neutrality and commissioned the Institute of Energy Economics and Rational Energy Use (IER) at the University of Stuttgart to calculate a total of three scenarios to this end.Whether with hydrogen, biological gas or electricity from renewable sources, the key to climate neutrality is to replace natural gas in the long-term, as it currently makes up 77 percent of the energy mix. To do this, conventional melting vats would have to be replaced by fully electrical or hybrid technologies. However, these are not yet market-ready, so much research and development is still needed in the coming years. For the first time, the costs for transforming the glass industry have been calculated along with the roadmap: the industry would have to invest approx. EUR 4.5 billion to refit the sector with climate-neutral melting vats.

There are currently various projects underway for this purpose. “NextGen Furnace”, a project by glass manufacturer Ardagh, receives financial support both from the Federal Ministry of Economic Affairs and Climate Action (BMWK) and from the Competence Centre on Climate Change Mitigation in Energy-Intensive Industries (KEI). Over the course of the year, the plan is to construct a melting vat which is heated mostly through electricity at the Ardagh site in Obernkirchen. In future, 80 percent of the electricity is to be generated from renewable energies, and the remaining 20 percent of energy needed supplied by a conventional oxygen and natural gas firing system. The plan is to thus reduce carbon emissions by 60 percent, and also by using a large percentage of glass shards in production. The plant is intended to be a reference technology for the entire glass container industry in future.

At the beginning of 2023, the project H2Glass was also launched, which is supported by European funds from the EU funding programme for research and innovation Horizon Europe. The international project with 23 glass industry partners, which is planned to last four years, is coordinated by the Norwegian company Sintef, and focuses on promoting hydrogen technologies and intelligent production systems for decarbonising the glass sector.

Not all projects are successful. The European joint project “Furnace for the Future” for climate-neutral glass production did not receive any support from the ETS innovation fund of the European Union, one of the world’s largest programmes for financial aid to promote and demonstrate innovative carbon-reduced technologies. The 19 participating companies had also planned to construct a hybrid electric melting vat which would be able to produce glass of any colour and which would use a large proportion of recycled glass. The new technology was supposed to make it possible to operate electric melting vats with a capacity of more than 300 tonnes per day. Without the EU grant, the project cannot continue as originally planned.