Phasing out SF6 in switchgear: the European timetable

A very effective gas, and a very problematic one

Sulphur hexafluoride, or SF6, has been used for decades in circuit breakers, switchgear panels and gas-insulated substations. It insulates remarkably well and quenches the electric arc that forms when current is interrupted. It makes compact installations possible, which is valuable in cities and on constrained industrial sites.

Its drawback is major: it is the most potent greenhouse gas known, with a global warming potential tens of thousands of times that of CO2, and an atmospheric lifetime of several thousand years. Every leak counts.

The timetable of Regulation 2024/573

The European regulation on fluorinated greenhouse gases, in force since 2024, prohibits putting into operation new electrical switchgear that uses these gases for insulation or breaking. The ban advances in steps:

The text provides for specific cases, in particular when no fluorinated-gas-free solution is available, or for equipment ordered before it came into force. Existing switchgear can keep operating, be repaired and serviced, provided neither the quantity of gas nor its climate impact increases. The official text published on EUR-Lex is authoritative on the details of these conditions.

The alternatives

Manufacturers have developed several families of solutions, which do not perform equally at every voltage:

• dry air or nitrogen for insulation, combined with vacuum interrupters for breaking, especially at medium voltage;
• gas mixtures with a low global warming potential, for higher voltage levels;
• air-insulated designs, bulkier, where space allows.

For extra-high voltage, solutions exist but are more recent, hence the later 2032 deadline.

What it changes in a project

The timetable applies to the date of putting into operation. A substation designed today and energised in three years must therefore already comply with the rule that will apply on that date. In practice:

• check the applicable deadline for each voltage level of the project, against the planned commissioning date;
• adapt the civil works: some SF6-free solutions are bulkier or heavier than the switchgear they replace;
• review operating and maintenance procedures, tooling and team training;
• anticipate procurement lead times, as the whole industry switches to this new equipment at the same time;
• for existing assets, keep the gas inventory, leak checks and end-of-life recovery up to date.

The SF6 phase-out therefore touches substation engineering, procurement and operations at once. It is a long-term undertaking for grid operators, industrial companies and their technical teams through to 2032.