For decades, one gas has helped make modern switchgear compact, reliable and capable of handling high voltages.

That gas is SF₆ — sulfur hexafluoride.

It is an excellent electrical insulator and arc-quenching medium.

It is also an extremely powerful greenhouse gas, with a 100-year global warming potential approximately 23,500 times that of CO₂, according to the U.S. Environmental Protection Agency.

SF₆-Free GIS Has Reached 170 kV

At CIGRE Paris 2026, GE Vernova launched its new F35g 170 kV gas-Insulated Switchgear, designed to deliver high-voltage GIS performance without SF₆.

The new product extends the company’s SF₆-free transmission portfolio across 72.5 kV, 145 kV, 170 kV, 245 kV and 420 kV.

GE Vernova has been developing its g³ alternative technology for around a decade.

What matters about the latest launch is not simply another switchgear model. It shows how far SF₆ alternatives have moved from an environmental experiment toward commercially available grid equipment.

Why Has SF₆ Been So Difficult to Replace?

There is a reason SF₆ became widely used in modern switchgear.

It combines strong dielectric performance with excellent arc-extinguishing properties, allowing electrical equipment to remain relatively compact while safely handling high voltages and fault currents.

That has made SF₆ particularly valuable in gas-insulated switchgear where installation space is limited.

The environmental problem appears when the gas escapes into the atmosphere.

Manufacturers therefore face a difficult engineering challenge: remove SF₆ while maintaining the reliability, dielectric performance, switching capability and compact footprint expected from modern switchgear.

The transition away from SF₆ is being driven by both technology development and changing environmental regulation.

In Europe, This Is No Longer Just About Sustainability

For equipment buyers, regulation may now be just as important as technology.

Under the European Union’s updated F-gas Regulation, restrictions on putting new electrical switchgear using fluorinated greenhouse gases into operation are being introduced according to voltage level, subject to specified exemptions and conditions.

This makes 2026 an important turning point for parts of the medium-voltage switchgear market.

For European projects, buyers increasingly need to think beyond the familiar questions of rated voltage, rated current and short-circuit capability.

The insulation medium itself is becoming part of the procurement specification.

What Should MV Switchgear Buyers Ask?

GE Vernova’s latest product is high-voltage transmission equipment, well above the voltage range used in most industrial distribution projects.

But the wider SF₆ transition is directly relevant to medium-voltage procurement.

Buyers sourcing 10 kV, 12 kV, 24 kV, 35 kV or similar MV equipment should increasingly confirm:

• Insulation and breaking medium
• Destination country and applicable regulation
• Rated voltage and rated current
• Short-circuit withstand and breaking capability
• Environmental and installation conditions
• Maintenance requirements
• Long-term gas servicing and replacement requirements

Is the SF₆ Era Ending?

Not overnight.

Millions of SF₆-containing devices remain in operation worldwide, and different markets will move at different speeds.

But two changes are now happening simultaneously.

Manufacturers are pushing SF₆-free technology into increasingly high voltage classes.

At the same time, regulators are beginning to restrict fluorinated gases in new electrical equipment.