I thought that this was the case but I did some reading and I was very surprised at how little HVDC lines lose - roughly 3% per 1000km (a lot less than AC transmission).
The new Ultra high voltage lines in China and elsewhere are even more efficient.
This explains why the Chinese are able to keep their power generation capacity so far away from their main population centres.
You lose a lot more energy moving electricity through small wires then oil in tanks.