A simple water heater is more clever than it seems

Technology Connections have a video about how water heaters work in detail and how much power can be saved by strategically turning them off when not needed. ▶ this video However, the website has some weird vibes as well, like why would you say something like below? > And some just want Dad Mode for when your teenager needs to finish that shower.

The water heater is always refilling. Otherwise you’d have no hot water pressure. It’s just that the new water goes to the opposite end of the tank from where the output is attached. How twin heating element water heaters work: ▶ this video

The efficiency of hot water heaters is actually surprisingly good. A modern insulated tank retains heat very well. And it's more flexible for heating options since the water can be heated slowly over time. You can now get heat pump water heaters that are more efficient than tankless heaters. [0] Water heaters are actually pretty clever, in a low-tech sort of way. Technology Connections did a good video about them recently. [1] 0: link 1: ▶ this video