The electrical industry accelerates the transition towards the elimination of Sulphur Hexafluoride (SF6)

We foster the development of sustainable alternatives to Sulphur Hexafluoride (SF6)

The coming into force of new European Directives forces switchgear manufacturers to replace sulphur hexafluoride (SF6), a gas widely used as an insulator and arc extinguisher in electrical switchgear, with alternative gases, due to its staggering global warming potential.

For this reason, TECNALIA offers the sector its critical testing infrastructure to guarantee the safety and certification of new equipment.

European regulatory framework and SF6 phase-out

In compliance with Regulation (EU) 2024/573 on fluorinated greenhouse gases, a strict time line has been established for the reduction and phase-out of SF6 in the electrical sector.

• These directives impose gradual bans on the marketing of new equipment using this gas, forcing the industry to migrate towards “SF6-free” technologies.
• The goal is clear: to replace SF6 with new insulating gas mixtures, pure air or vacuum technologies that maintain operational efficiency while drastically reducing environmental impact.

Technical complexity of phasing out SF6

The phasing out of SF6 is not a simple process, as this gas has superior dielectric properties enabling the size of equipment to be reduced. The change directly affects:

• Medium voltage cells: redesign of insulated compartments.
• Circuit breakers: development of interruption chambers and arc extinguishing resources.
• High voltage isolators and circuit breakers: adaptation of the insulation distances and the water tightness of the tanks.
• Voltage measuring transformers: elimination of the presence of SF6 with the necessary redesign.

We support industry in terms of electrical validation through testing

Any change in the gas composition or geometry of the equipment alters the electrical behaviour, which makes rigorous validation by regulatory testing essential.

To mitigate the risks associated with the development of these new products, TECNALIA offers manufacturers an advanced technological capacity to accompany the entire product life cycle; from the initial R&D phases to final certification.

Critical infrastructure and testing for design validation

Given the criticality of the new designs, TECNALIA offers its specialised facilities to the sector to carry out critical tests to validate the design, such as:

1. Short Circuit Testing: verification of the equipment's ability to withstand extreme mechanical stresses during failure, ensuring that the new designs and materials respond appropriately.
2. Short-circuit making and breaking tests. Validation of the breaking capacity of the new designs. One of the most important challenges for medium-voltage switchgear manufacturers is to achieve a combination of gases and materials with similar capacities and sizes to existing ones.
3. Internal Arc Tests: essential tests to ensure operator safety by assessing the strength of the enclosures and pressure management in the event of an internal failure.
4. Dielectric Tests: validation of the insulating capacity of new mixtures and new designs of busbars, switchgear and measuring equipment.
5. Heating tests: validation of the thermal performance of the equipment. These tests are vital to check that the new gases and insulating materials do not compromise the operating temperature, avoiding premature degradation of components and ensuring the service life of the equipment.

With this infrastructure, TECNALIA is positioned as a key ally for electrical switchgear manufacturers to comply with environmental regulations without compromising the reliability and safety of the energy infrastructure.