Small polysilicon producer REC Solar Norway has claimed a carbon footprint of 11.2kg CO2-eq per kg silicon, which was verified by EPD Norway and published Environmental Product Declarations (EPDs) for solar grade silicon and for multicrystalline silicon blocks made by REC.
REC Solar Norway, formerly Elkem Solar and a subsidiary of REC Group, is said to have an annual production capacity of more than 8,000MT, equating to around 2.5GW of PV module production.
The company uses a specific metallurgical purification method to produce polysilicon that is claimed to reduce energy consumption by 75%, compared to the Siemens process. The ‘modified’ Siemens process also reduces material wastage and improved energy usage, while Fluidized Bed Reactor (FBR) technology further reduces energy usage over the modified Siemens process.
REC’s EPDs are developed according to Product Category Rules (NPCR 029 – v1.1) managed by EPD Norway and are created based on a Life Cycle Analysis (LCA), which is in turn carried out in accordance with relevant ISO standards and guidelines, according to REC Group.
Overall, REC Group said that its polysilicon had the lowest climate impact of any solar grade silicon product being produced today.