ELI5: Explain Like I'm 5

Water heat recycling

Water heat recycling is just like recycling anything else. Instead of throwing away water that has been used and is now hot, we use it a second time. The hot water is sent to a special tank or machine where it is cooled down and then sent back to the shower, sink, or toilet for another use. This means that less water is wasted, and the hot water can be used over and over again.