> Because it doesn’t keep a big tank of water heated and ready to be delivered to any house tap, tankless water heaters save energy—up to 34 percent, according

> Because it doesn’t keep a big tank of water heated and ready to be delivered to any house tap, tankless water heaters save energy—up to 34 percent, according to the Department of Energy. Yes, perhaps compared to electric heated tanks - though the latter require a lower continuous power and can be planned against peak demand. However, heat pump water heaters which dump their heat in a tank are much more efficient.