≈1.6 t direct (anodes, PFCs) plus 0–15 t indirect depending on power source. Hydro-powered smelters land near 2 t total; coal-powered near 16–18 t. CBAM counts both for aluminium.
From our guide: Decarbonizing Aluminium — full context, charts and sources there.
Boilers, kilns, heat exchangers, valves and steam lines lose energy continuously. Inzonex makes patented (UK GB2508992.1) removable modular insulation — snap-fastened covers engineered per temperature tier, not generic off-the-shelf jackets: