US washing machines use hot water (often heated with gas).

How is saving energy inferior?

US machines use many, many times the quantity of water and detergent and are
an environmental nightmare.

European machines used to have heating elements and a separate hot fill to
start it off. This is no longer done as the machines use so little water
that there is no energy to be saved when you account for the lost hot water
in the pipework every time it fills.

Christian.