Hitachi Energy is launching a new technology that is meant to tackle emissions of sulfur hexafluoride (SF6), of which the power sector uses 80% of total gas produced.
Hitachi Energy claims it has launched the world’s highest voltage SF6-free switchgear – the EconiQ 550 kV circuit breaker that can be used in gas-insulated switchgear (GIS) or dead tank breakers (DTB) and the EconiQ 420 kV Live Tank Breaker (LTA). This equipment is meant to replace SF6 switchgear around the world, including in China, which is the source of 57% of the global SF6 emissions, Hitachi Energy said.
Sulfur hexafluoride (SF6) is widely used in switchgear. Overall, it makes up 220 million tons of CO2 equivalent or 0.6% of global emissions. It is 24,300 times more climate-hostile than CO2 and remains in the atmosphere for over a thousand years – much longer than CO2, which lasts less than 200 years, Hitachi Energy said.
While industry standards mean that leaks are minor and accidental releases of SF6 rare, Hitachi Energy said private stakeholders and regulators alike are reluctant to continue using SF6, a gas they see as an environmental threat and liability.
“It’s hard to overstate the critical role that this little-known gas plays in keeping the lights on,” said Markus Heimbach, Executive Vice President and Managing Director of the High Voltage Products Business Unit at Hitachi Energy. “It has been as central to building our modern world as steel and concrete.”
“This makes SF6 exceptionally challenging to phase out,” Heimbach said. “The industry can only overcome the dual challenges of strict SF6 regulations and rising transmission demands with solutions that eliminate this gas without sacrificing size or performance. Our new EconiQ technology is the first to meet this critical need. Hitachi Energy is the first to have come up with sustainable products for this voltage level, where the largest portion of SF6 is used.”
Hitachi Energy said it’s providing the industry’s only SF6-free solutions for these voltage ratings, which it says maintain the same footprint, dimensions, compatibility, lifespan, safety, reliability, and efficiency as traditional SF6 equipment. This is meant to allow utilities and operators to plan SF6 phaseout roadmaps, enabling them to swap components, retrofit, and install new systems with only minor technical changes and minor new training needs.
Both new EconiQ products have pilot orders confirmed and form part of climate commitments from utilities, Hitachi Energy said. In North America, where the 550 kV voltage is common, two customers have placed orders for the new EconiQ 550 kV DTB, Hydro One and WesCo.
Hydro One is Ontario’s largest electricity transmission and distribution service provider, servicing nearly 1.5 million predominantly rural customers across the state. The EconiQ eco-efficient dead tank breaker will be used to support Hydro One in its goal to minimize the installation of new SF6 assets and proactively minimize operational releases of SF6 from in-service assets.
Wesco, a Pittsburgh, Pennsylvania-based electrical distribution and services company, will use the EconiQ eco-efficient 550 kV dead tank breaker to help fulfill its customers’ sustainability goals for 2030 and beyond.
SF6 has been used since the 1950s for electrical equipment in high-voltage substations, replacing bulk oil, minimum-oil, and air-blast circuit breakers throughout the 1970s and 1980s. As a non-toxic and non-flammable insulator, it’s no secret why it was seen as an ideal choice for decades in high-voltage electrical equipment like circuit breakers and gas-insulated switchgear (GIS).
However, SF6 has a 23,500 times greater global warming potential (GWP) than CO2 as a greenhouse gas over a 100 year time frame. The vast majority of its increase in concentration in the Earth’s troposphere since the 1980s can be attributed to its use in the power sector.
