Energy management systems and control of washing machine, dryer, and property

An automatic control of variably and unattended controllable consumers (WW, battery, e-car) makes sense and works out-of-the-box with the relevant photovoltaic manufacturers. Of course, I use that.

None of this applies to the dishwasher, washing machine, dryer requested here: they are not variable but can only be on/off. They do not run unattended but must be loaded/unloaded manually. And out-of-the-box nothing runs there at all – understandably. Whether you need a control for the one press of the "Start" button is up to each individual to decide.

To solve the mixing valve puzzle: we had that in place anyway so that there is no standing water in the domestic hot water line there.

We connected the washing machine to a WW mixing faucet

So simply a "mechanical" mixing faucet like in a shower or bathtub or something electronic?
It then supplies a maximum of 30 degrees to the hot water line of your washing machine capable of handling hot water, right? You don’t want to run the "rinse" mode with warm water and waste energy here...

Correct, cheap, mechanical mixer tap that stubbornly delivers 30°. You then use the hot water buffer of the heat pump as a storage tank. And the hot water buffer can be easily operated with photovoltaic surplus.

To solve the mixer battery puzzle:

That wasn't really a puzzle. Nevertheless, welcome information, because that's exactly what this thread is about: Energy management systems and control of washing machine, dryer, and dishwasher A hot water connection is just as suitable here as demand control. Terms and studies on Smart Grid, Cleanthinking, THINQ, Demand Side Flexibility, EEBUS, etc. provide plenty of reading material for anyone interested in such things.

That doesn't change the fact that the possibilities and the technology are now available and we are heading towards a world where things like demand-driven consumption will sooner or later be considered given or taken for granted.

Can you give me a concrete example of how this could look with the household appliances mentioned here in the thread?
I lack the imagination here. I can still imagine that in a single household or with a couple, but not with a family. Nobody willingly adjusts themselves to the sun or other things when the laundry or dishes are piling up.

No one voluntarily aligns themselves with the sun or other things when the laundry or dishes are piling up.

Nobody does that either. Everything is optional here. Such things are not yet part of the Energy Saving Ordinance or other regulations, even though we are clearly heading in that direction. What specific example do you need? For instance, fill the dishwasher and, if you like, put the last coffee cup in in the morning. Then go to work. In the afternoon/evening when you come back, the dishes will have been washed if the surplus electricity from the roof was available. This works equally well for singles, couples, and families. The same applies to other household appliances. Usually, you don’t have to watch the washing machine while it washes, and it can run during your absence. Furthermore, you can also set the time windows specifically so that the laundry doesn’t have to wait for hours in the washing machine for the residents’ return. The advantage compared to a simple timer control that is already known and has now reached end users is that you don’t have to enter it anew every time; you just close the lid. The technology takes care of the rest.