It seems more sensible to heat the water at the tap
That would be luxurious, yes, but it's the more technically challenging/expensive option. You need a heater in every tap, and you have to run 10AWG or a gas hardline to every tap.
(I happen to have been contemplating the feasibility of this on my own)
I confess to being facetious with my comment which is probably not cool because though I believe this whole preoccupation with carbon emissions to be a scam, the idea of wasting energy bothers me on a natural level, so that long before global warming I washed my hands with cold water.
That would be luxurious, yes, but it's the more technically challenging/expensive option. You need a heater in every tap, and you have to run 10AWG or a gas hardline to every tap.
(I happen to have been contemplating the feasibility of this on my own)