Collaboration of air-water heat pump, photovoltaic system and storage

Yes, all good ideas. But: putting the heat pump into the day - is the sun always shining then? The sun rises, the photovoltaic system starts. The normal consumption is covered. Afterwards, the storage is charged with max 3kW. But the photovoltaic system produces more than base load + charging the storage. Then the heat pump starts to heat the domestic hot water. So base load + storage + hot water are still less than what the photovoltaic system produces, the excess goes into the grid. Same if the storage is full. Or do you think you can charge a storage with 7-10kW power?!

Yes, all good ideas. But: putting the heat pump into the daytime - does the sun always shine there?

No, but the probability is higher. Besides, photovoltaics also work without the sun shining brightly. With air-to-water heat pumps, there is also the advantage of a higher source temperature.

The sun rises, the photovoltaics start working. The normal consumption is covered. Afterwards, the storage is charged with max 3 kW. But photovoltaics generate more than the base load + storage charging. Then the heat pump starts heating the domestic hot water. So base load + storage + hot water are still less than what photovoltaics produce, the excess goes into the grid. Same if the storage is full. Or do you think you can charge a storage with 7-10 kW power?!

That’s not perfection, which is why it’s good that the feeding-in alone already covers the system. But you can definitely optimize a bit to consume as much photovoltaic power yourself as possible.

I have a 6.8 kWp photovoltaic system on the roof. My record this year was 45 kWh in one day, the total household consumption including hot water was 15 kWh. No matter how you twist and turn, you can’t sensibly use this amount of energy from the roof, even with storage and overcharging hot water.

Also one reason why storage systems are, in my opinion, (still) nonsense. Apart from all the losses, degradation, maintenance charging in winter... in summer it’s full and standing idle, in winter it’s empty.

Excess feeding-in, yes!

Another reason why storage systems are, in my opinion, (still) nonsense. Apart from all the losses, degradation, preservation charge in winter ... in summer it stands full in the corner, in winter it is empty.

Our "provisional" battery storage with currently 9.6 kWh was, in this December - which I believe belongs to the winter months - repeatedly almost full at noon. Since I have not yet connected the monitoring for evaluation (there are also still provisional inverters), but just occasionally check the devices, I cannot state the number of charge cycles; I would not be surprised if the number were greater than 12. Earlier, 8 kWh were again charged into the storage - and the base load of the house was running. There is no preservation charge over the winter or standing empty. You apparently assume that there are never clouds or darkness in summer and no sun in winter. I have not experienced the seasons that way.

Our "provisional" battery storage with currently 9.6kWh was almost fully charged around noon several times this December – and I believe December counts as one of the winter months. Since I have not yet connected the monitoring for evaluation (the inverters are still provisional as well), and only occasionally check the devices, I cannot state the number of charge cycles, but I would not be surprised if the number exceeded 12. Earlier, another 8kWh were charged into the storage – and the house base load was running at the same time. There is no maintenance charging over the winter or standing empty. You apparently assume that there are never clouds or darkness in summer and never sun in winter. That is not how I have experienced the seasons.

How big is your photovoltaic system?
I live in the west; even on sunny December days more than 3 kWh have not come from the roof.
But if you come around with a 20 kWp system output, then that fits again.

Nominally 9.99kWp - 9W rated power per photovoltaic tile, 1110 pcs. in total. How much goes into the storage depends not only on the yield but also on the consumption curve. Our house has a low base load and a number of consumers that draw quite a bit of power when in operation. As long as these are not used, quite a bit goes into the storage.

to the TE: Such a system is calculated based on knowledge of the assumptions made. Then the assumptions are varied and a result corridor is obtained against which one can measure their decision. A battery storage can be worthwhile or expensive depending on the consumption curve, which becomes quite clear then.

Such a system is calculated with knowledge of the assumptions one makes.

That is initially my problem: I have no knowledge and must first laboriously read up on it in theory.

And then, in practice, "optimize" it a bit.
It's already good for me to hear that the charging process of the storage occurs only with a part of the energy, and the rest is consumed as usual.

I thank you all and wish you a happy New Year!