New build bungalow - air-water heat pump, photovoltaic and solar thermal?

Yes, the fireplace is planned anyway, as a luxury.

But something doesn't fit here:
Town & Country house and then a fireplace as a luxury?

In my circle of acquaintances, I haven't heard such good things about that.
Before I maybe spend €5,000 on a fireplace and stove (+ chimney sweep annually), I would rather invest the money in geothermal energy or in a better-equipped house.

Because of the buffer, I thought it was necessary anyway because of the underfloor heating.

No, it is not necessary. A well-designed underfloor heating system has enough volume to store heat.

Good and bad reading can be a lot :confused:

It is also not necessarily certain with us that Town & Country or the franchisee MBB GmbH will become our partner. That was our first personal contact and it was relatively pleasant. We have already made another appointment to "calculate". Although I try to remain as objective as possible.

What I have read so far about geothermal energy were quite high costs for earthworks and defective probes. And a chimney is just luxury, that is certain ;) Or do you mean that Town & Country generally does not stand for "luxury"?

So far I have not found any great recommendations for construction companies from Berlin/Brandenburg.

Town & Country I associate, from all hearsay, somehow more with El Grande Cheapo.

Town & Country is for bargain hunters. But it doesn’t matter, if it fits, it fits.

Solar thermal painting is pointless due to the lack of a buffer (no, the underfloor heating is not for that, otherwise you’ll be roasted in your place in summer – ST is for hot water!). ST and photovoltaics hardly support the heat pump in winter because of little sunlight. Battery storage is uneconomical anyway (you say 20 years, compared to 10 years warranty from the manufacturer), especially with a heat pump as a large electricity consumer. With that, you already achieve a high self-consumption rate.

Geothermal energy can be worthwhile especially with KFW 55 and smaller area = low heating demand. Then the subsidies (4.5-5K € BAFA) almost cover the drilling costs. Alternatively, ground/ditch collectors are very attractive, especially for people who can offer self-labor (small excavator etc.), as the subsidy then exceeds the construction costs, so you can come out with a profit.

If own effort is possible, then the trench collector is ideal. If not: drilling with us costs about €12,000 at a company here.
Underfloor heating as a buffer is meant more in the way that the water volume achieves the circulation volumes required by the heat pump with correct design, and thus no unnecessary buffer storage is needed. Likewise, a bypass valve is then unnecessary.
That’s also why solar thermal should be left out, because it then becomes difficult to control or the heat pump starts to become completely uneconomical.
The hot water in summer is then not made by solar thermal but by the heat pump with photovoltaic support.
Important for the heating system, however, is: correct calculation of the heating load, room by room. For this, have the underfloor heating correctly designed with as low a supply temperature as possible. How this is done you can read on the internet.

Own work is hardly feasible. My girlfriend works in an office and I come from IT. So basically two left hands :D Some parquet laying or painting work is okay but nothing more. Since the sun isn’t that intense in our area, I hope to increase self-consumption with a storage system in combination with the photovoltaic system. Because during the sun hours we are at work. As far as I have read so far, geothermal energy has slightly better efficiency than an air-water heat pump. But how is it with frozen ground? In a thread here I read something about 80cm, which I find a bit too little. Although I have no clue about it either.