Air-water heat pump current consumption and data

When I moved in December, I lowered the set temperature at night slightly so that the heat pump runs mostly during photovoltaic production times. From 5:00 am, it goes back to normal temperature so there are no cold feet in the morning. Out of pure laziness, this is the only "optimization" so far.

Since March, I have been over 90% self-sufficient; today in April the total consumption was 283 kWh (heating, hot water, ventilation, household), of which 15 kWh was grid consumption and 750 kWh fed in. Year-to-date total consumption is 1,740 kWh, grid consumption 655 kWh (470 of which was in the stupid January), and 2,425 kWh fed in. I am more than satisfied :D

All this with 170 sqm of space in the permafrost region of Hochsauerland (we still have night frost). I could certainly optimize the heat pump consumption further... but given these values I somehow lack the motivation.

Since March, I have been over 90% self-sufficient; in April today, the total consumption was 283 kWh (heating, hot water, ventilation, household), of which 15 kWh was grid consumption and 750 kWh fed in. Year-to-date total consumption is 1,740 kWh, 655 kWh grid consumption (of which 470 in the annoying January), and 2,425 kWh fed in. I am more than satisfied :D

All of this in 170 sqm of space in the permafrost region of Hochsauerland (we still have frost at night). I could certainly optimize the heat pump consumption... but considering the figures, I somehow lack the motivation.

How should this be read? For April, that would mean a daily total consumption of 12 kWh? Household electricity alone would usually exceed that.

That can’t be right? And if it were, then photovoltaics would be completely uneconomical with such low consumption. Enlighten us.

Yes, you are right - photovoltaics are complete nonsense... I just consume too little ;)

What is supposed to freeze and what is the heating element supposed to do against it? Theoretical fear of events that do not exist at all.

Of course, it also depends somewhat on the type of heat pump. We have a monoblock installed outdoors, where the supply and return lines go directly to the heat pump, and freezing of the pipes is very real in this case.

That can’t be true, can it? And if it were, then photovoltaics would be completely economically nonsensical at such low consumption levels. Enlighten us.

Photovoltaics pay for themselves, self-consumption is just the cherry on top.

Of course, it also depends somewhat on the type of heat pump. We have a monoblock installed outdoors, so the supply and return go directly to the heat pump, and freezing of the pipes is very real.

There are >150 liters of tempered water inside, the vast majority of which takes heat from the ground and the room. So nothing freezes that quickly. Maybe right at the device or near the building if no circulation is taking place anymore. An internal circulation pump would also rule that out, as would check valves and a valve for draining.

Apart from that, if that is real, why isn’t there any antifreeze in the system?

Photovoltaics pay for themselves, self-consumption is the cherry on the cake.

A photovoltaic system doesn't even pay for itself with self-consumption and feed-in under 12 years. How is it supposed to pay for itself at all without self-consumption? I'm curious about that! I just calculated it, the payback period is over 20 years. Then the thing is junk. You can forget about it completely :). But that doesn't include insurance or the inverter breaking down within that time. In practice, you're probably looking at 25-30 years.