Solar system, water-heated stove, passive house, heating costs in winter

Hello!

We are currently planning our house construction. It is to be a passive house without a basement with about 260m2 of living space and an open living area (living room/dining room/kitchen). The south/west sides around the living area will be generously glazed. At the moment, we are thinking about the heating concept. Since one of our big wishes is a cozy tiled stove in the living room, the idea of a water-bearing system comes to mind. We are currently leaning towards heating the whole thing with solar collectors and exactly this water-bearing stove (underfloor heating). Since we definitely want the stove anyway and have the wood available ourselves, this would, in our opinion, also be a fairly cost-friendly system.

We are now wondering how much/how often one would actually have to heat with it in winter and how well these systems work...

I would be very happy about suggestions. At the moment, we are still quite early in the planning...

.... It is to be a passive house without a basement with approx. 260m2 living space ......As one of our biggest wishes a cozy tiled stove in the living room is, the idea of a water-carrying system arises.

Without exact dimensioning, this can become problematic. It is not uncommon for the installation rooms to be overheated. How is the heat supposed to be distributed?

.... We are now wondering how much/how often one actually has to heat with it in winter and how well these systems work...

These questions are clarified, among other things, with the basic assessment => actual demand (capacity, energy) for heating and hot water.

.... Currently we are still quite early in the planning...

That is a big advantage, because time pressure is by far the worst advisor in construction.

Regards

Without exact dimensioning, this can become problematic. It is not uncommon for the installation rooms to overheat. How is the heat supposed to be distributed?

It should be done via underfloor heating. The stove is to be located in the open living/dining/kitchen area, so it is in the largest room of the house and the resulting direct waste heat can be well distributed. It would be interesting to know how well these water-bearing systems work and what distribution of waste heat/feed-in is possible.

...Should be done via underfloor heating.

I would reconsider that. Underfloor heating is slow and does not really fit with the partly faster processes of solar and internal gains.

...The stove should stand in the open living/dining/kitchen area,...

But then in a central place, for example as a room divider, and not "crammed" into a corner. The direct output should not be significantly greater than the calculated room heating load.
The coziness factor of the tiled stove from grandma’s times is largely based on radiant heat. The intensity of radiation depends on the surface temperature.
PH can manage with an air heating system at suitable locations with sufficient planning, i.e. no water-based heat distribution.
At less favorable locations, a water-based heat distribution is more sensible, albeit with higher effort.
There are situations where there is no heating demand, but hot water must be produced and solar coverage is currently not available. The direct heat emission in the installation room then cannot be avoided.
Additionally, it is possible that with the water-based stove, due to hot water demand, the storage was charged. Depending on the state of charge, any subsequent, now available solar offer can no longer be used or only insufficiently. The economic efficiency of the solar thermal system thus deteriorates significantly, depending on user behavior.

In my opinion, tiled stove, solar thermal system, and PH do not really go together. I would rather prefer a heat pump and possibly photovoltaics here. In the annual balance, heating and hot water are thus possible at virtually "zero cost" without manual effort under appropriate conditions. If necessary, a small wood stove with minimal output in the large installation room for the occasional fire experience.

Precise statements can only be made once the actual demand (power, energy) for heating and hot water as well as regional climate data are known.

Best regards

Here I would think again. Underfloor heating is slow and doesn’t really match the sometimes faster processes of solar and internal gains.

Yes, I’ve also read that in a technical book... there they rather suggested wall heating (is that the correct term?) for this case. Somehow the idea of underfloor heating is still a bit more appealing to me... for hammering nails, hanging shelves, etc. But it will certainly be discussed in more detail. Maybe I also have to let go of some "traditional" views in order to find an optimal solution.

--> The stove would really stand centrally between the living room and dining room as a room divider, so you can also sometimes use it as a cozy TV/reading bench. A friend of mine heats with geothermal energy (flat collectors) and is quite enthusiastic about it – for me, on the other hand, the idea is not so appealing... the whole garden full of pipes and operating the heat pump with electricity.

I get the firewood from my own forest, so a log wood stove seems future-proof and cost-effective to me. A wood gasifier was the first choice at first, but the more we move towards a passive house, the more oversized it seems to me. And as I said -> the tiled stove is a "must have" for us, so the water-bearing stove seems quite attractive to me. I also work a lot from home, so heating in winter would not be a big problem.

It would be very interesting for me if someone uses this solution and how satisfied they are with it....

Thanks first of all for the food for thought.

The best option is surface heating, either wall or ceiling heating as a capillary tube system. A wall heating is not a folded-up floor heating as most people think. The approach is not only completely right for a passive house but also for any other form. Enormous amounts of energy are saved solely through the capillary tube system, and there is the possibility of air-conditioning the building in summer by means of the ground temperature of 14-16°C (near-surface use).

Energiefuxx