SF₆-Free Switchgear: How Clean Air and Vacuum Circuit Breakers Are Shaping Medium-Voltage Distribution
SF₆-Free Switchgear: How Clean Air and Vacuum Circuit Breakers Are Shaping Medium-Voltage Distribution
The electrical power industry is witnessing revolutionary changes in the development of switchgear devices because of technological advancements.
Sulfur hexafluoride (SF₆) has been common in electric equipment for decades due to its wonderful insulating and arc-extinguishing qualities, but controversy regarding its excessive GWP resulted in the necessity to look for alternatives. And more and more often regulations and sustainability of the equipment are becoming an inspiration for its design.
In 2026 an innovative switchgear that works without using SF₆ device and employs the vacuum interruption technique has become a topic for numerous discussions in the electrical power sphere. CIGRE Paris Session 2026 is meant to present technical information on the application of the devices that use alternative insulation and operate with the use of dry air as well as vacuum isolation devices from medium voltage and high voltage electricity transmission.
In terms of medium voltage electricity distribution networks, one of the most advanced technologies appears to be:
dry air insulation + vacuum interruption technology.
Reasons to Leave SF₆ Behind
Thanks to its outstanding dielectric and arc-extinguishing properties, SF₆ has traditionally been used in switchgear for many years.
Note that this gas is characterized by a very high global warming potential, and so the industry has decided to shift to the use of other technologies aimed at phasing out the use of SF₆ at both the transmission and the distribution levels. Thus, the industry is working on vacuum switching technology and the use of other insulation media instead of SF₆.
Some other reasons that motivate the transition are as follows:
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Compliance with environmental regulations
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Decrease in greenhouse gas emissions
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Achievements of long-term goals related to the decarbonization of power grids.
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Increasing demand for sustainable electrical equipment
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Development of alternative insulation and interruption technologies
The transition does not mean that one alternative technology will replace SF₆ in every application.
Instead, different voltage levels and applications may require different technical approaches.
For example, current industry development includes natural-origin gas mixtures, fluoronitrile-based alternatives, technical air and vacuum interruption technologies.
For medium-voltage distribution, dry-air insulation combined with vacuum interruption is one particularly important direction.
What Is SF₆-Free Switchgear?
The SF₆-free switchgear is the name thought for electrical switchgear, where sulfur hexafluoride has not been used as the medium for insulating or interrupting purpose.
But the term SF₆-free does not refer to just one technology.
Different methods can be applied according to the voltage class and configuration of equipment.
Some of the methods are as follows:
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Application of dry air or technical air for insulation
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The method of interruption in vacuum
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The use of mixtures with natural gases
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The use of gases based on fluoro compounds
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Other means of insulating and interruption
It is significant for buyers.
If one is searching for the medium-voltage SF₆-free switchgear, it cannot be assumed that all the equipment works similarly.
The decision must be taken based on the rated voltage, rated current, short-circuit current breaking value, installation conditions, configuration, and requirements.
Why Combine Clean Air with Vacuum Interruption?
One of the most practical approaches for medium-voltage switchgear is to separate two functions:
Insulation → Dry air
Arc interruption → Vacuum
A vacuum interrupter provides the switching and arc-extinguishing function, while dry air is used as the insulation medium.
The suggested combination makes it possible for the equipment manufacturers to remove SF₆ from the primary insulation and interruption mechanism without sacrificing the functionality of the medium voltage distribution devices.
This design can be especially appealing for distribution purposes due to its unique mix of:
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Being free of SF₆
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Using vacuum switching technology
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Featuring a fully insulated construction
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Having the equipment sealed
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Being compact for medium voltage devices
The development of this technology does not concern only one manufacturer.
Many studies concerning SF₆-free switchgear, vacuum circuit breakers and dry air insulation are already part of the CIGRE technical program for 2026 reflecting that the alternative methods for switching and insulating systems play an important role in the development of international grid equipment.
Where Is SF₆-Free Switchgear Being Applied?
SF₆-free technology is developing across different voltage levels.
At the high-voltage and transmission level, 2026 industry developments include SF₆-free circuit breakers and GIS at voltage levels such as 170kV, 245kV, 420kV and beyond. CIGRE 2026 materials also discuss vacuum circuit breakers and alternative gas technologies for high-voltage applications.
For example, GE Vernova announced a 170kV SF₆-free GIS at CIGRE Paris 2026, while CIGRE technical materials discuss emission-free 245kV and 420kV vacuum circuit breakers using clean-air insulation.
These developments demonstrate that the industry is working to extend SF₆-free technologies into higher voltage classes.
However, medium-voltage distribution is a different market.
For utilities, industrial facilities, renewable energy plants and distribution networks, equipment in the 10kV/12kV and 35kV/40.5kV classes represents an important practical application area.
This is where dry-air RMUs and vacuum circuit breakers can provide a direct equipment-level pathway toward SF₆-free distribution.
SF₆-Free Medium-Voltage Distribution: The EUE Power Approach
EUE Power's product portfolio includes the CKAS-12 Eco-Friendly Gas-Insulated Ring Main Unit (RMU).
The CKAS-12 uses dry air as the insulating medium and a vacuum interrupter for arc extinction.
The disconnector switch and vacuum interrupter are fully enclosed within a stainless-steel tank filled with dry air. The equipment uses a fully insulated and fully sealed design, with an IP67 enclosure rating for demanding outdoor environments.
Key parameters include:
This makes the CKAS-12 particularly relevant to customers looking for SF₆-free RMU technology for 10kV-class medium-voltage distribution systems.
Vacuum Circuit Breakers: From 12kV to 40.5kV
Vacuum circuit breakers are another important part of the transition toward cleaner medium-voltage switching technologies.
EUE Power's high-voltage vacuum circuit breaker range covers 12kV and 40.5kV, corresponding to 10kV and 35kV power systems.
The product range includes rated currents from 630A to 4,000A and short-circuit breaking current options from 20kA to 50kA, depending on configuration.
These ratings make the products applicable to a range of medium-voltage distribution environments, including:
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Substations
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Industrial and mining facilities
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Urban distribution networks
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Rural distribution networks
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Automated distribution systems
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Applications requiring frequent switching operations
For customers evaluating medium-voltage circuit breakers, the important point is that the transition toward vacuum switching is not limited to one specific equipment configuration.
Vacuum technology can be integrated into different types of switchgear and distribution equipment depending on system requirements.
What Should Buyers Consider When Selecting SF₆-Free Switchgear?
Choosing an SF₆-free switchgear product should not be based only on whether the equipment is labeled "green" or "eco-friendly."
For a technical buyer, several parameters are more important.
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Rated Voltage
First confirm the actual system voltage.
For example:
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10kV systems commonly use 12kV-class equipment
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35kV systems commonly use 40.5kV-class equipment
The equipment's rated voltage and insulation level must match the requirements of the electrical system.
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Rated Current
The rated current should be selected according to the load and network configuration.
For RMUs and circuit breakers, customers should consider both normal operating current and expected future load growth.
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Short-Circuit Breaking Capacity
This is one of the most important technical parameters when selecting a circuit breaker.
The required breaking capacity depends on the prospective short-circuit current of the electrical network.
EUE's vacuum circuit breaker range includes breaking current options from 20kA to 50kA depending on the configuration.
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Insulation Medium
Buyers should confirm what replaces SF₆.
"SF₆-free" may refer to different technical architectures.
For medium-voltage applications, dry air combined with vacuum interruption is one available approach.
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Environmental Conditions
Outdoor equipment may face:
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Rain
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Dust
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High humidity
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Temperature variations
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Coastal environments
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Industrial pollution
For this reason, enclosure protection, sealing and insulation design should be considered alongside the electrical specifications.
The EUE CKAS-12, for example, uses a fully insulated and fully sealed structure with an IP67 enclosure rating.
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Application and Configuration
The same voltage level does not necessarily mean the same switchgear configuration.
Customers should define whether the equipment will be used for:
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Ring network distribution
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Feeder protection
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Substation applications
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Industrial power distribution
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Renewable energy collection systems
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Urban or rural grid modernization
A qualified manufacturer should then select the appropriate product configuration.
Is SF₆-Free Switchgear the Future of Medium-Voltage Distribution?
The answer is increasingly clear: SF₆-free technologies are becoming an important direction for the development of power distribution equipment.
But the transition will not happen through one universal technology.
Different voltage levels and applications will require different engineering approaches.
At the transmission level, the industry is developing alternative gas and vacuum technologies for increasingly high voltage ratings. CIGRE 2026 provides clear evidence of this direction, with technical work covering SF₆-free GIS, vacuum circuit breakers, dry-air insulation and alternative gas mixtures.
At the medium-voltage level, dry-air insulation combined with vacuum interruption is already a practical equipment architecture.
For utilities, industrial users, renewable energy facilities and distribution equipment buyers, the key question is therefore not simply:
"Can SF₆ be replaced?"
A more useful question is:
"Which SF₆-free technology provides the right electrical performance, environmental characteristics and configuration for this application?"
That is where product-level engineering and manufacturer experience become important.
EUE Power: Medium-Voltage Switchgear Manufacturer and OEM/ODM Partner
EUE Power supplies power distribution equipment for international customers, with a product portfolio covering switchgear, ring main units, vacuum circuit breakers, transformers, instrument transformers and metering equipment.
For medium-voltage distribution applications, our relevant product portfolio includes:
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12kV SF₆-free RMU
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12kV vacuum circuit breakers
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40.5kV vacuum circuit breakers
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Medium-voltage switchgear
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Intelligent outdoor vacuum switching equipment
The CKAS-12 provides a dry-air and vacuum-based approach for 12kV-class RMU applications, while EUE's vacuum circuit breaker portfolio extends to 40.5kV-class medium-voltage systems. EUE Power also supports OEM/ODM requirements, allowing qualified customers to discuss product specifications, configurations and market-specific requirements directly with the manufacturer.
Looking for SF₆-Free Medium-Voltage Switchgear?
Tell us your:
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System voltage
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Rated current
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Short-circuit level
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Installation environment
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Required quantity
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Target delivery schedule
Our team can recommend the appropriate product configuration based on your requirements.
Frequently Asked Questions
What does the term SF₆-free switchgear refer to?
The answer to this question is simple. SF₆-free switchgear does not use sulfur hexafluoride as its insulating or interrupting medium. The particular technology used, however, depends on the application and voltage level in question. Dry air technology, vacuum interruption technology or alternative mixtures of gases may be employed.
What is the difference between SF₆-free switchgear and vacuum switchgear?
Both terms are related to one another in that both have to do with power switchgear. The difference arises in that the term “SF₆-free” means that there is no SF₆ involved, whereas the term “vacuum switchgear” refers only to the use of vacuum interruption technology. So it is possible to have a design that uses both technologies, such as dry-air insulated RMU that uses vacuum interrupters.
What voltage levels does EUE Power's SF₆-free RMU support?
The SF₆-free RMU of EUE Power is CKAS-12 Eco-Friendly RMU which is a 12kV product made using dry-air insulating technology and vacuum interruption technology that works with rated current of 1,250A.
Does EUE Power supply 40.5kV vacuum circuit breakers?
Yes, it does. The portfolio of EUE Power in high-voltage vacuum circuit breakers also includes circuit breakers rated at 12kV and 40.5kV.
Is SF₆-free switchgear suitable for renewable energy projects?
SF₆-free medium-voltage equipment can be considered for applications such as distribution networks and renewable energy facilities, subject to the project's electrical specifications, protection requirements, environmental conditions and applicable standards.
Conclusion
The transition away from SF₆ is becoming an important development in the global switchgear industry.
The change from using SF₆ gas has become a crucial moment in the switchgear industry worldwide.
Manufacturers and service providers are employing more sophisticated technology that does not use the SF₆ gas at the level of high-voltage.
At the same time dry-air insulation and vacuum interruption make it possible to achieve cleaner designs of switchgear at the level of medium-voltage.
For equipment buyers, the priority should not simply be choosing the newest technology.
It should be selecting the right voltage class, current rating, breaking capacity, insulation technology and configuration for the actual power distribution application.
EUE Power has launched its 12kV dry-air and vacuum RMU and 12kV/40.5 kV vacuum circuit breaker that will meet the demand for next generation equipment in the field of medium-voltage distribution.
Do you want to purchase 12kV SF₆-free RMU or 12kV/40.5kV vacuum circuit breaker? Get in touch with EUE Power to discover hardware and technical details.
