The construction sector represents a critical focal point for environmental sustainability. According to data from the European Commission, it accounts for 40 percent of energy consumption and 36 percent of total emissions. As highlighted at the VITRUM25 conference, Building as Green as Glass, sustainability concerns extend beyond emissions from operational energy use – named operational carbon and responsible for about two-thirds of total building emissions – to embodied carbon, the remaining third of emissions arising from the materials used in construction, including glass.
Data from Assovetro shows that Italy is the second-largest flat glass manufacturer in Europe by volume. While glass production is generally considered sustainable, it still emits 10-11 kilograms of CO2 per square metre, posing an environmental challenge.
To address these issues on a European scale, Glass for Europe, the association representing flat glass manufacturers, is actively promoting flat glass as an eco-friendly solution and working to reduce the sector’s environmental impact. Over the past 25 years, emissions from glass production have dropped by 43 percent. Today, 75 percent of these emissions stem from the fossil fuels – primarily natural gas – used in the melting process, with the remaining 25 percent linked to CO2 released from carbonates in raw materials.
Reducing, let alone eliminating, the 75 percent of emissions from the melting process is highly complex. The most effective solution would be an energy switch to renewable sources, such as biogas, hydrogen, or electricity. In the Czech Republic, a collaboration between multinational corporations Saint-Gobain and AGC has led to the development of a pilot line for flat glass production that will significantly cut CO₂ emissions by using a hybrid power system, combining 50 percent electric energy with 50 percent oxygen and gas. This presents a dual challenge: it requires both accelerated technological advancements and the establishment of economically viable conditions, particularly access to competitively priced green energy.
To address the remaining 25 percent of emissions from raw materials, recycled glass, known as cullet, can be used. Cullet lowers the melting point of the glass mixture, reducing energy requirements and CO2 emissions by limiting the need for virgin raw materials. Currently, cullet makes up an average of 26 percent of the glass mixture used in European flat glass production.
Compared to container glass recycling – where Italy is a leader thanks to the 1997 Ronchi Decree, which fostered effective public-private partnerships – recycling flat glass for building purposes is more complex. This is due to stringent requirements for quality, transparency, and purity. Eurovetro, which currently recycles around 18 percent of Italy’s glass (about 700 million bottles), has made flat glass recycling a primary growth driver over the past five years. The company now recycles over 100,000 tonnes of flat glass annually and will open a new facility in San Vito al Tagliamento (PN) in late 2023.
Eurovetro has also developed Isomix, a new product in collaboration with the glass research center Stazione Sperimentale del Vetro. Isomix is a refined, white glass sand created to purify recycled flat glass, offering consistent quality without impurities, even after prolonged periods in melting furnaces.
The main challenge remains integrating recycled flat glass into the market as new products usable within the same production cycle. This requires significant technological investment and close collaboration across the industry to understand standards, needs, and operational constraints, all while ensuring quality, durability, and sustainability.
The path forward involves strengthening collaboration within the glass industry, creating an efficient circular model that can reduce emissions and optimize resource use. This, among other topics, will be a focal point at VITRUM, scheduled to take place at Fiera Milano from 16 to 19 September 2025.