Regardless of their comparatively small contributions thus far, emissions of the fuel are ticking up, and the progress fee has been climbing yearly. SF6 emissions in China practically doubled between 2011 and 2021, accounting for greater than half the world’s emissions of the fuel.
Now, corporations want to get rid of gear that depends on the fuel and looking for replacements that may match its efficiency. Final week, Hitachi Power introduced it’s producing new gear that replaces SF6 with different supplies. And there’s momentum constructing to ban SF6 within the energy business, together with a not too long ago handed plan within the European Union that may section out the fuel’s use in high-voltage gear by 2032.
As gear producers work to supply alternate options, some researchers say that we should always go even additional and are looking for options that keep away from fluorine-containing supplies solely.
Excessive voltage, excessive stakes
You in all probability have a circuit-breaker field in your house—if a circuit will get overloaded, the breaker flips, stopping the move of electrical energy. The facility grid has one thing comparable, referred to as switchgear.
The distinction is, it usually must deal with one thing like one million instances extra vitality than your property’s gear does, says Markus Heimbach, govt vice chairman and managing director of the high-voltage merchandise enterprise unit at Hitachi Power. That’s as a result of elements of the ability grid function at excessive voltages, permitting them to maneuver vitality round whereas shedding as little as attainable. These excessive voltages require cautious insulation always and security measures in case one thing goes fallacious.
Some switchgear makes use of the identical supplies as your property circuit-breaker bins—there’s air round it to insulate it. However when it’s scaled as much as deal with excessive voltage, it finally ends up being gigantic and requiring a big land footprint, making it inconvenient for bigger, denser cities.
The answer right now is SF6, “an excellent fuel, from a know-how perspective,” Heimbach says. It’s capable of insulate gear throughout regular operation and assist interrupt present when wanted. And the entire thing has a a lot smaller footprint than air-insulated gear.
The issue is, small quantities of SF6 leak out of kit throughout regular operation, and extra might be launched throughout a failure or when outdated gear isn’t dealt with correctly. When the fuel escapes, its robust capacity to entice warmth and the truth that it has such an extended lifetime makes it a menace within the ambiance.