Comment by ZeroGravitas

Australia has some cutting edge tech that actually sends control signals through the electric wires.

It rolled this out in 1953:

https://en.wikipedia.org/wiki/Zellweger_off-peak

It let coal plants run more efficiently and people could heat their water overnight.

Somewhat bafflingly they seem to have somewhat failed this same task with the solar rollout.

Presumably 21st century capitalism got in the way of the mid 20th century engineering.