"One of the big levers for decarbonizing our global energy is by connecting
continent-scale grids with high-voltage direct current transmission (HVDC).
We’ve been doing a lot of that already, but a lot more is planned. There are
about 200 GW of HVDC cables stretching 58,000 kilometers in operation today,
and about 180 GW planned stretching about 45,000 kilometers in planning and
construction. The large majority of what’s in operation is in China, of course.
Let’s start with the why. As delayers love to say, the wind doesn’t blow all
the time and the sun doesn’t shine all the time. But go north, south, east, and
west a few hundred or a couple of thousand kilometers, and the weather is
completely different. We’ll be overbuilding renewables in the best places and
connecting them to the highest demand centers like major cities, ports and
industrial sites. The sun may not shine brightly during peak demand periods of
the late afternoon and early evening, but it’s shining brightly a couple of
time zones or more to the west.
But traditional transmission using high-voltage alternating current (HVAC)
loses a lot of energy over longer distances, and a lot more if you have to go
underwater or underground with the cables. HVDC loses a lot less energy over
great distance, underwater, and underground, about 3% for every 1,000
kilometers. That’s the most efficient mechanism for transmitting energy we’ve
It’s so effective and so efficient that it’s hard to keep up with all of the
projects. Enter RTE International, a consultancy and engineering company whose
activities cover all areas of electricity transmission. They keep track, as
best as they are able, of all existing and planned HVDC projects globally. They
publish updates as part of their monthly HVDC newsletter, something I’ve been
receiving and digging through for a while now."
*** Xanni ***
Chief Scientist, Xanadu
Partner, Glass Wings
Manager, Serious Cybernetics