One of the most common questions in any household is this: does it use more energy to leave the electric water heater on all day or only turn it on when needed?Many myths have arisen around this question regarding savings, consumption, and the lifespan of the water heater. In this guide, we'll calmly debunk them and explain how to use your water heater efficiently, without sacrificing comfort.
Common myths about electric water heaters and energy consumption
Before going into technical details, it is worth reviewing some of the most widespread myths about the use of electric water heaters.
Myth 1: “If I leave it on all day, it uses much more energy”
A well-insulated water heater doesn't heat water continuously: it only activates when the temperature drops below a certain threshold. The rest of the time, it simply maintains the heat with very low energy consumption.
Myth 2: “It’s best to turn it on only before showering”
This can lead to more intense and longer heating cycles, resulting in higher consumption peaks than stable maintenance.
How much energy does an electric water heater actually consume?
The water heater heats the water to a set temperature (for example, 60–75 °C) and then switches off. The tank's insulation retains the heat.
- Thermal dispersion: This indicates how much energy the water heater loses in 24 hours. An efficient water heater loses very little heat.
- Insulation: It has a greater impact on savings than whether it is switched on or off.
Is it worth leaving it on?
It depends on your water heater. In many cases, it is more cost-effective to keep it on with proper regulation than to be constantly turning it off and on.
Reasons to leave it on:
- When the thermos has good insulation.
- When there are several showers spread throughout the day.
- When it is a low-consumption water heater with fast recovery.
How to use your water heater to save money without sacrificing comfort
- Adjust the temperature: You don't need 75°C; a moderate temperature reduces consumption.
- Take advantage of the fast recovery: An efficient water heater offers more hot water with fewer liters of storage.
- Plan according to your electricity tariff: If you have time-of-use pricing, heat during off-peak hours.
Examples of low-consumption water heaters
Ecothermo Titan One
30L water heater with the equivalent capacity of over 100L thanks to its rapid recovery. See Ecothermo Titan Uno
Ecothermo Titan Dual
60L model with dual storage tanks, offering an equivalent capacity of over 250L. See Ecothermo Titan Dual
