warm it up every time it gets cold
use insulation to keep the water hot for 40 minutes
keep it in a hot place
polystyrene
No, It doesn't. If you want to keep hot water hot for a longer time use a polystirene cup.
PEX pipe will keep it hot longer than copper.
thaw it under the sink with hot water. then keep it in a bucket of hot water
try covering the glass, so the heat particles stay inside the cup, and the hot water stays hot.
To keep the water hot longer. Saves on heating costs.
Hot water works just keep rubbing hot water and soap it happend to me
Metalic cups keeps the water cold and it can be also used to keep the water hot .
So the steam can rise from the boiler to the hot water tank storage
Metal is a conductor of heat