Toshiba Launches SF₆-Free 420/550 kV Gas-Insulated Busbar Using Natural-Origin Gas

Toshiba Energy Systems & Solutions Corporation has commercialized a new gas-insulated busbar (GIB) that completely eliminates sulfur hexafluoride (SF₆)—a greenhouse gas nearly 25,000 times more potent than CO₂. Using only natural-origin gases, the new GIB supports rated voltages up to 550 kV and is now available for order, offering a major step forward in sustainable power infrastructure.

GIBs are essential substation components, connecting transformers, switchgear, and transmission lines while relying on high-pressure insulation gas within a sealed metal tank. While SF₆ has long been the industry standard due to its exceptional insulating properties, its extremely high global warming potential has prompted growing regulatory pressure, particularly in Europe and North America.

Under its AEROXIA™ brand, Toshiba is transitioning transmission and distribution equipment to natural-origin gases—such as nitrogen, oxygen, and carbon dioxide—with GWPs lower than CO₂ and without any synthetic fluorinated gases. Following its first SF₆-free GIS (72/84 kV) delivered in 2022, Toshiba is now expanding the portfolio with a high-voltage GIB for extra-high-voltage substations.




The newly launched 420/550 kV GIB achieves high voltage-withstand performance using a high-pressure CO₂–O₂ gas mixture. A specialized coating protects insulating surfaces exposed to electric fields, enabling a compact, rational design fully compatible with existing SF₆-based equipment—critical for large-scale substations where GIB length and volume are substantial.

Utilities in Japan and worldwide, along with renewable energy operators, are increasingly seeking natural-gas-insulated equipment to eliminate SF₆ while ensuring stable, sustainable power delivery. Toshiba plans to accelerate development of natural-gas-based GIS technologies above 220 kV, reinforcing its commitment to environmentally responsible innovation.