Single-family house - 18,000 kWh in two years - what could be the problem?

Hello everyone,

I need to get in touch here in the forum because I need your opinion and advice.

We (2 adults with 2 small children) have been living for two years in a single-family house with a [Einliegerwohnung]. This apartment has been rented out for one year (2 adults with a baby).
Our house has a geothermal heat pump (Nibe 1245 PC). It provides hot water, heating, and passive cooling through the floor.

The main meter shows 18,000 kWh.
That seems extremely high to me and I can’t explain where that is supposed to come from?!

Could the energy supplier’s meter be defective?
Could a device, e.g. the heat pump, refrigerator, stove, etc., be defective so that it draws more electricity?

I’m somehow still at a loss.

Many greetings

Write something about the settings of the pump.

For example, flow temperatures, hot water temperature.

Does the ground source heat pump have an additional heating element?

Hello,

do you mean the main meter of the heat pump?

Don’t you have separate meters there for yourself and the granny flat?

Then you can’t really bill correctly – or can you?

In addition, there are small measuring devices as plug adapters for end devices (under €10) that can do short- or long-term measurements.

Just buy 2 and plug them behind each cooling device. Let them run for 1 week, read them, and be amazed.

Can you quickly tell me which settings you need to get an idea? Yes, she has a heating rod, which we initially used for drying heating. However, I deactivated it afterwards.

What does it mean for a device to be defective? Does everything depend on one meter?

So 9000 kWh per year for 2 families with heating? Sounds normal.

So we have 4500 household electricity, 5 people, one of whom lives in the granny flat.

But that means 2 refrigerators, respectively 2 kitchens, and with babies and children more laundry, then heating lamps above the changing table.

How many m2 are heated including the basement and auxiliary rooms?

do you mean the total meter of the heat pump?

No, the total meter from the energy supplier at the transfer point.

Don’t you have separate meters there for you and the granny flat?

Oh, that brings us to the next problem, which our then developer (who sold his business before finishing his work) didn’t consider.
We have one meter from the energy supplier for the entire electricity. Then the electrician installed a meter in the meter cabinet for the usable electricity in the apartment.
But no one seemed to care that hot water, heating, and cooling run on electricity via the heat pump.
So the granny flat has the electricity meter for usable electricity (2500 kWh in that one year), but the rest runs through the heat pump, which in turn is connected to the total meter :-( To make matters worse, we are chasing the energy supplier for a whole year to get a separate meter for the heat pump.
Sounds complicated, right? For me, absolutely horrible, because when it comes to service charge billing, I’m a bit lost.

There are also small measuring devices as plug-in meters for end devices (under €10) that can do short- or long-term measurements.
Just buy 2 and plug them behind each cooling device. Let them run for 1 week, read them off, and be surprised.

Yep, I just got some now and have found nothing surprising so far,... except for the FLM, the exhaust air module for energy recovery. It draws 150W at night from 9:00 pm to 9:00 am, and only 20W during the day. And we have two of these devices. One for the granny flat directly on the heat pump, and one in my living unit in a separate room. So at night 300W, during the day 40W. That’s quite a chunk. It’s set up so that I pull in cold air through the fresh air valves at night in summer and only minimal warm air during the day.
That’s also a problem because the FLM for the granny flat should be on the granny flat’s electricity meter. Right now, they both run completely on the total meter.

That should have been done differently from the start, I realize that, but I trusted the planner and architect too much without questioning. How could I have, I had no clue about heat pumps, ventilation systems, and granny flats. That’s only slowly changing now as I start to deal with this stuff.