How can my fancy new dishwashers “ECO” mode last 5 hours? How is that good for the environment?

Question

How can my fancy new dishwashers “ECO” mode last 5 hours? How is that good for the environment?

In: 9984

Answer 1

* Heating up water takes a ton of energy.
* Spraying it around takes MUCH less energy.

Result: Heating the water to a lower temp but spraying it around for much longer does the same amount of cleaning for less energy, it just takes longer.

(Less ELI5: Water has a high heat capacity, meaning it can absorb a lot of thermal energy and not get much warmer. That’s why water-cooling things works so well. Sadly it means when you *want* hot water, that takes a ton of energy as well.)