News Release

～Significantly reduces greenhouse gas emissions in transmission & distribution equipment～

Toshiba Energy Systems & Solutions Corporation (Toshiba) has commercialized a gas-insulated busbar (GIB^*1) that completely eliminates the use of sulfur hexafluoride (SF₆), a highly potent greenhouse gas, and instead uses natural-origin gases. The newly developed GIB supports rated voltages of up to 550 kV, and is designed to advance sustainable power infrastructure by significantly reducing environmental impact. The GIB is now available to order.

GIBs are core components of substations, used to connect transformers, switchgear and transmission lines, and transmit power between them. Similar to other power transmission and distribution equipment, GIBs use a high-insulation gas contained under high pressure within a hermetically sealed metal tank to electrically insulate the high-voltage conductor from the tank.

For decades, the exceptional insulating performance of SF₆ made it the industry standard. However, SF₆ also has an extremely high global warming potential (GWP): it is nearly 25,000 times more effective at trapping heat in the atmosphere than CO₂, and is now a significant issue worldwide, facing growing regulatory restrictions, especially in Europe and North America.

To address this, Toshiba has introduced the AEROXIA™^*2 brand of transmission and distribution equipment that uses only natural-origin gases—such as nitrogen, oxygen, and carbon dioxide—with GWPs lower than that of CO₂, and that does not use any artificially synthesized fluorinated gases, like SF₆. Toshiba manufactured its first SF₆-free product, a 72/84 kV gas-insulated switchgear (GIS^*3) for a substation in Japan, in 2022, and is now launching its new high voltage GIB product.

Extra-high-voltage substations are the backbone of the power transmission and distribution network and require large, long GIBs, resulting in the use of large volumes of SF₆ being used for insulation. Toshiba has successfully replaced the conventional SF₆-based insulation systems with systems using natural-origin gases, while maintaining full compatibility with current equipment dimensions.

The newly commercialized 420/550 kV GIB enhances voltage-withstand performance by enclosing a high-pressure gas mixture of carbon dioxide and oxygen. Featuring a specialized coating on insulating areas exposed to high electric field, it also achieves a rational size design fully compatible with existing SF₆-based equipment.

Power utilities in Japan and overseas, and renewable energy providers, are showing strong interest in transmission and distribution equipment that uses natural-origin gases, as it eliminates SF₆ and ensures both stability and sustainability in power supply. Going forward, Toshiba will accelerate the development of GIS using natural-origin gases for backbone power systems above 220 kV, and contribute to a sustainable society through environmentally-responsible innovation.

Notes:

• Gas-insulated busbar (GIB): Equipment mainly used in substations to connect switchgear, transmission lines, and transformers over a wide area, and that plays a key role in power transmission. Alongside GIS, GIB is essential for compact and highly reliable high-voltage substation equipment.
• AEROXIA™: The specific gases and mix ratios are selected according to voltage class and required performance.
  For further details, please refer to the AEROXIA™_Brandbook (PDF)(8.53MB).
• Gas-insulated switchgear (GIS): Equipment comprising circuit breakers, disconnectors, surge arresters, and instrument transformers, used to isolate faults and switch transmission systems in substations.