It's the first time I own a dryer.
When I poured out the water it has collected (a few liters per run) I quickly tested the EC and pH and found out, that it is almost identical to the one made by my reverse osmosis filter!
No wonder, since the dryer is basically just a big distillation machine.
Thats super neat. It will save me a lot of work filtering tap water.
I will collect it from now on and use it for watering my plants.
Why does it matter?
Plants really don't like tap water. Even in a country like mine, where no chlorine/ fluoride/ whatever is added, the dissolved minerals cause trouble. They will build up over time and make nutrients unavailable, even if you adjust the pH.
The buildup and nutrient lockout will harm the plants a lot in the long term, and you will have way more trouble checking and correcting EC and pH.
Heat pump driers use a bit of electricity to get up to temperature then a tiny amount to run the compressor and keep the heat topped up thought the cycle, they can take longer for some fibres (ones they have high resistance to airflow and also like to hold on to water) but they use far less energy to do that. The amount of energy used is not consistent through the wash.
Some loads my machine takes just over 1kWh (25p) to dry, maybe 2.5 hours, other loads take 30mins and 0.3kWh. (~8p)
If this is supposed to be some kind of contradiction to me saying watts, then obviously you need to integrate it over time and arrive at the total used. It was just an example of how something could take longer but use less in total, not a detailed description of how a drier works. But thanks anyway