Rio Tinto uses GOs for aluminium smelter in Iceland

Rio Tinto’s ISAL aluminium smelter in Iceland uses Guarantees of Origin (GOs), a form of Energy Attribute Certificates (EACs), to evidence that its electricity consumption is matched with renewable hydropower generation. These certificates allow the company to attribute low-carbon status to its aluminium by tracking renewable energy use in market accounting terms. There is a stronger shift towards relying on GOs, reflecting tighter scrutiny of renewable claims and raising broader questions about how such certificates are used in European energy and emissions accounting systems.