ᐅ Electricity Consumption of a Heat Pump

Thank you for all the interesting contributions!
I cannot find a convincing explanation for the electricity consumption at 4:00 AM.
Why would the heating element always turn on at the same time during the night if no hot water is being used?

xMisterDx schrieb:

Insane. You have to be close to brain-dead to argue about the purpose and sizing of a photovoltaic system based on its daily performance, especially in winter.
It’s like two diesel drivers arguing — both traveling on the A2 highway... but one driving alone and empty at 100 km/h (62 mph), and the other fully loaded at 180 km/h (112 mph). That’s the (intellectual) level being displayed here right now.

That’s exactly why statistics exist. They provide, for example, average values over many years...
And they clearly show that in December you can only expect about 15% of the yield from July from photovoltaics. That there might be a day with higher output at MyGoodness doesn’t matter to statistics or anyone except MyGoodness and RotorMotor.

Also, the idea that a 45° south-facing orientation is optimal is false. You reach 100% output with a 28° south-facing orientation. If you’re going to nitpick and call others fools, MyGoodness...

If you see this as a “low-level argument between people close to brain death,” that’s your perspective (even though I don’t understand why people start discussions with insults).
I was simply responding to this statement by Buchsbaum:

Buchsbaum schrieb:

Photovoltaic yields are very low from November to February. Today I had 3.5 kWh yield, which was already a lot.

I wanted to point out that there can be more productive days even in winter. Of the 17 days in December so far, I’ve had more than 15 kWh yield on 5 days, and more than 20 kWh on 3 of those. Compared to his 3.5 kWh, which he considers “a lot,” I was below that only on 6 days.

You even support my statement by saying the average yield in winter is about 15%. For me, it’s a bit higher, which I believe is due to the 45° roof pitch (low sun angle in winter and all that...).

xMisterDx schrieb:

Also, the claim that a 45° south-facing tilt is optimal is incorrect. You reach 100% with a 28° south-facing tilt. If you’re going to nitpick and call others fools, MyGoodness...

I never claimed otherwise. You should read carefully. My exact statement was that 45° “brings a lot in winter,” and I still stand by that. A friend of mine has the same system as me just one street away but with a 25° roof pitch. Over the last three years, we compared yields, and my system has consistently performed better in winter, while his performs better in summer.

marienschatten schrieb:

Thank you very much for the many interesting posts!
I cannot see a convincing explanation for the electricity consumption around 4:00 AM.
Why would the heating element always turn on at the same time during the night if no hot water is being used?

It is not about hot water being used, but rather about keeping the water at a certain temperature.
That is probably why the heating element turns on at night.

marienschatten schrieb:

Thank you very much for the many interesting contributions!
I cannot find a convincing explanation for the power consumption around 4:00 AM.
Why would the heating element always turn on at the same time during the night when no hot water is being used?

But you are also doing nothing to get an answer here.
Why don’t you answer the questions asked about your generally high electricity consumption?
Or about the heat pump?
Or about the 5 kW peak loads or the higher consumption occurring multiple times a day?
Or, or, or.

I don’t see anything special about 4 o’clock. The whole day is unusual in your case, without further explanation.

Glad to have sparked an engaging discussion.
Answering all questions doesn’t seem very helpful to me. I was only concerned about an inexplicable anomaly.
The heating element only turns on briefly, but never for hours, and certainly not at night.
I will show the graphs to the heating technician today. Let’s see if they have an explanation.

Best regards,
Bernd

xMisterDx schrieb:

It is also not true that a 45° south-facing angle is optimal. You achieve 100% at a 28° south-facing angle.

Of course, a steeper installation angle is better in winter because it provides a better angle to the low sun. However, over the whole year, a slightly flatter angle yields more due to higher summer output. Naturally, yields are lower in December than in June, simply because the day is 8 hours shorter. Average values only poorly reflect the actual situation. In winter, there are many days with only 200W at midday and some very good days where you mostly feed energy back into the grid.

Yields can also be very localized. On Saturday, conditions were great here; on Sunday, the storage system charged up in the morning before it clouded over again. Ten kilometers away, the sun stayed out until the evening.

marienschatten schrieb:

The heating element only switches on briefly, but never for hours, and certainly not at night.

Just go into the menu and deactivate the heating element. It’s really not necessary anyway.