eli5, how does a city hot water system work? How does hot water remain heated while traveling through pipes to our faucets?

Question

Hello everyone, recently my city has been doing some repairs to the city’s hot water system and i was without hot water for about 3 weeks.

That got me wondering, how exactly does this work? I read something about a heating agent but i don’t know what that means. And how does the water stay hot while travelling from the place it gets heated to our homes?

Thanks!

In: 25

Answer 1

The city I lived in in Switzerland also had it.

The answer is thermal insulation, the hot water pipes had VERY thick insulation around them.