SEE (Specific Embedded Emissions) refers to the total greenhouse gas emissions generated in producing one unit of a product. For aluminium, this calculation covers emissions from both the direct production process and the electricity used.

SEE calculation for aluminium is more complex than in other sectors, because the emissions profile varies significantly depending on the production route (primary/electrolytic vs. secondary/recycled) and the technology used.

At the heart of primary aluminium production is the electrolysis process (the Hall-Héroult process). Alongside carbon dioxide, this process can also release perfluorocarbon (PFC) gases, which have a far higher global warming potential.

PFC emissions occur during what's known as an "anode effect" that occurs periodically in electrolysis cells, and can contribute disproportionately to the total carbon footprint.

One of the commonly used methods for calculating PFC emissions is the overvoltage method. Rather than relying on the frequency and duration of anode effects, this approach is based on the deviation in the electrolysis cell's operating voltage.

The overvoltage method tends to produce more practical and consistent results, particularly for modern facilities with continuous monitoring data — but applying it correctly requires the facility's voltage data to be properly recorded.

Because aluminium production is an extremely electricity-intensive process, indirect emissions can be comparable to — and often exceed — direct emissions.

Whether the electricity used comes from the grid average or from a direct production source has a direct impact on the indirect emissions calculation, which is why accurate documentation matters so much here.

SEE calculation in the aluminium sector requires managing multiple variables correctly at once — different production routes, the choice between PFC calculation methods, and electricity source documentation. A single wrong assumption can significantly shift the total emissions figure.

That complexity is why aluminium exporters are better served running their SEE calculation with a team that has sector-specific technical knowledge, rather than a generic template.