H2Si - Silicon Production from Quartz and Hydrogen

The H2Si project, known as "Silicon Production from Quartz and Hydrogen," is on a mission to revolutionize how we produce silicon by completely eliminating CO2 emissions. This initiative is a key part of Elkem's ambitious plan to achieve carbon-neutral silicon alloy production by 2050, potentially cutting down CO2 emissions by a eliminating 1.5 million tonnes each year from its Norwegian smelters. Currently, silicon production relies on high-temperature chemical reactions between quartz (silicon dioxide, SiO2) and carbon, which unfortunately generates CO2 as a by-product. Specifically, for every kilogram of silicon produced, approximately 5 kilograms of CO2 are emitted into the atmosphere. As silicon is acknowledged by the EU as a critical material for the green transition—utilized in aluminium alloys, silicones, electronics, and the manufacturing of renewable energy technologies such as solar cells, wind turbines, and batteries—developing a method for its production that eliminates these emissions is essential. The H2Si project aims to tackle this challenge by recycling carbon and hence eliminating direct CO2 emissions during silicon production. This innovative approach uses hydrogen to convert process off-gases into methane, which is then thermally cracked to produce solid carbon. This solid carbon can then be used as a reductant in the silicon production process. By relying solely on quartz, hydrogen gas, and electrical energy, the project eliminates the need for coal and biocarbon, making the entire process more sustainable. The implications of the H2Si project could be transformative for the global silicon industry, significantly reducing CO2 emissions and enhancing sustainability in production methods. The project also lays the groundwork for further research through laboratory and bench-scale experiments to assess its industrial viability. It aligns perfectly with Elkem's climate roadmap and the broader goal of promoting sustainable industrial practices. The H2Si is initiated and led by Elkem and Sintef Norce and Future materials have been research partners in the project running from 2022 to 2024. The project has been run in close cooperation with all the partners. • SINTEF: has conducted essential laboratory testing on methanation technologies and gas treatment in addition to development of silicon process with a new raw material; recirculated carbon. • Future Materials has focused on scaling up the silicon production process and developing a new raw material based on the recycled carbon. They have the necessary equipment and facilities to optimize the production methods, ensuring that the innovations can be applied on a larger, industrial scale. • NORCE has contributed by developing models to evaluate the industrial applicability of the H2Si concept as well as modelling the process phenomena and mass and heat transfer in the silicon process. • Elkem have been deeply involved in planning, execution and evaluating the lab and bench scale experiments performed at SINTEF and Future Materials and have done the modelling to assess the industrial applicability of the H2Si concept. In addition, Elkem have financed mathematical modelling by externals. Recent findings confirm that this innovative method of recirculating carbon with hydrogen can indeed facilitate silicon production without any direct CO2 emissions. As a result, Elkem have decided to continue research and development on this concept. Building on the insights gained from H2Si, several new projects have been launched in 2024, including: • Elkem is partner in GreenBox a Green Platform project focusing on developing instrumentation and mathematical models of new processes. • Elkem has received funding from Enova for medium-scale pilot testing as a continuation of the H2Si project. • Elkem is initiator and partner in the Mecalo project, funded by the EU’s Horizon Europe program. This project seeks to demonstrate the total concept investigated in H2Si with carbon looping using hydrogen for CO2-neutral production for both silicon and manganese. In summary, the H2Si project represents a significant step forward in sustainable silicon production, aligning with global climate goals and paving the way for a greener future in the industry.

Silicon plays a crucial role in the transition to a sustainable society, serving as a key component in aluminium alloys, silicones, electronics, and renewable energy production, including solar cells, wind turbines, and batteries. Traditionally, silicon is produced by reacting quartz with carbon materials such as coal, charcoal, and wood chips at temperatures exceeding 2000°C. This process generates CO2 emissions, with approximately 5 kg of CO2 emitted for every kilogram of silicon produced. The H2Si project aimed to develop an innovative silicon production method that eliminates all direct CO2 emissions and recycles carbon from off-gases using hydrogen. Elkem, the project owner, is committed to industrializing this concept as part of its strategy to achieve carbon-neutral silicon production by 2050. The anticipated reduction in CO2 emissions from Elkem's Norwegian smelters is 1.5 million tons per year. The H2Si concept is a leading candidate for becoming the primary carbon-neutral technology for silicon production beyond 2050. Its successful industrialization is a priority in Elkem's long-term strategy, reducing CO2 emissions from silicon production and enhancing Elkem's competitiveness in the global silicon market. The project is being conducted from 2022 to 2024, with Elkem as project manager collaborating with research partners SINTEF, NORCE, and Future Materials. Laboratory-scale experiments are being conducted at SINTEF, while bench-scale experiments are taking place at Future Materials. Elkem is actively involved in planning, executing, and evaluating these experiments, taking responsibility for process modelling, while NORCE plays a key role in mathematical modelling. The new process developed through the H2Si project has the potential to revolutionize the global silicon industry by significantly reducing CO2 emissions and promoting sustainable production methods. Recent findings confirm that this innovative approach to recirculating carbon with hydrogen can facilitate silicon production without direct CO2 emissions. Continued research and development are recommended. Building on the insights gained from H2Si, several new projects have been launched in 2024, including: • Elkem is partner in GreenBox a Green Platform project focusing on developing instrumentation and mathematical models of new processes. • Elkem has received funding from Enova for medium-scale pilot testing as a continuation of the H2Si project. • Elkem is initiator and partner in the Mecalo project, funded by the EU’s Horizon Europe program. This project seeks to demonstrate the total concept investigated in H2Si with carbon looping using hydrogen for CO2-neutral production for both silicon and manganese. In summary, the H2Si project represents a significant advancement in sustainable silicon production, aligning with global climate goals and paving the way for a greener future in the industry.

The H2Si project’s innovation is to develop a novel concept for silicon production utilizing hydrogen, where all direct CO2 emissions are eliminated. The project owner Elkem’s objective is to develop and industrialize the concept, and it is a central part in Elkem’s strategy to achieve a carbon-neutral silicon production by 2050. The potential reduction in CO2 emissions from Elkem’s Norwegian smelters is 1,5 million tons/year. The H2Si concept with elimination of CO2 emissions is among the strongest candidate to become the main carbon-neutral technology for silicon production beyond 2050. The development and industrialization of this concept is a prioritized task in Elkem’s long term strategy to achieve a carbon-neutrality in silicon production. A successful industrialization of the concept will result in reduced CO2 emissions from silicon production in Elkem’s plants in Norway and give Elkem increased competitiveness in the global silicon market. It will also position Elkem for transfer of new environmental technology from its Norwegian operations. Elkem will licence the technology to other silicon producers and this may become a game changer for the silicon industry globally, providing cost efficient production of silicon at a minimal climate and environmental footprint. The project will go 2022-2024. Elkem is the project owner and SINTEF, NORCE and Future Materials will be research partners. The laboratory-scale experiments will be performed at SINTEF, while the bench-scale experiments will be performed at Future Materials. Elkem will be deeply involved in planning, execution and evaluating the lab and bench scale experiments performed at SINTEF and Future Materials and will be responsible for process modelling. NORCE will have a key role in mathematical modelling.