'A bullet train for power': China's ultra-high-voltage electricity grid
'A bullet train for power': China's ultra-high-voltage electricity grid
China produces more clean energy than any other country. Now it's rolling out an ultra-high-voltage grid to match – will its strategy of going big pay off?
Summary
China leads the world in ultra-high-voltage (UHV) power transmission, with 48,000km of UHV lines connecting remote renewable energy sources, like wind, solar, and hydropower, to urban centers.
UHV lines minimize energy loss over long distances, earning them the nickname “bullet trains for power.”
Initially designed for coal and hydro, these lines now support China’s renewable energy expansion.
However, challenges remain, including high costs, dependence on coal for stability, and limited local integration.
Globally, countries like Brazil and India are adopting UHV, but regulatory and cost barriers hinder broader deployment, especially in the U.S.
It sure took a long time to get down to this part:
In 2022, 56.2% of the electricity transmitted by UHV lines in China came from renewable sources, beating the government's target of "no less than 50%". But most of this was hydropower – which China classes as renewable and clean – a government report showed. While hydropower does not rely on fossil fuels, it has other environmental drawbacks, such as harming river health and releasing methane. The portion for wind and solar carried on the UHV lines is much lower, averaging 27.25%, according to an analysis of the report by Chinese thinktank Lingdian Energy.
Wait, how does hydro release methane?
To dam a river you flood the upstream portion to create a height difference in the river that your can use to generate electricity.
This flooding submerges MASSIVE amounts of vegetation which undergoes anaerobic decomposition releasing tons of methane. It's a one time thing, but it's actually up there when you include the expected lifetime of a hydro plant, and the fact that methane is a very powerful greenhouse gas.
More than a quarter is still pretty good. And I think most people would call hydro a renewable energy source. Still better than fossil fuels for sure.
They're building 2/3 of the worlds wind and solar capacity each year so this will likely just keep increasing.
We're still arguing about whether global warming is real and they're smashing it. A bit embarrassing really.