Is natural stone heating in combination with a photovoltaic system reasonable?

Hello €uro,

.. without considering ventilation heat losses, which would be urgently necessary.

I have already written that I am not an engineer and have left the calculations to a planning office. Only - somehow either you or I are missing something. In a natural stone heating system, ventilation heat losses play absolutely no role. The system uses the walls, ceilings, floors ... body - for example, the (massive) walls store the heat for up to 2 hours - the room air is always equally warm or cold; depending on the point of view. I don’t know if you have ever worked with such a system? You can imagine the functioning comparable to a “sunbath” in the mountains. The ambient temperature is minus x° and yet you hardly feel cold. That is why the rooms do not "suffer" as a result of longer ventilation phases either.

I would be very interested in these results. You can surely provide me with the numbers (calculation, actual energy consumption).

I no longer sell this system for several years because I was tired of running into the walls of the big energy suppliers. Accordingly, I also have no contact with my clients from that time. I might still be able to provide you with calculations (they should be found on the tapes of the respective data backups) – whether I still have invoices from the utilities, I dare to doubt – I am glad if I gain a little space every year (analogous to the 10-year retention period). You will have to believe my statements in case of doubt.

Kind regards

Hello construction expert,

....I have already written once that I am not an engineer and have also left the calculations to a planning office.

That is bad, if you move in fields of activity where you have no own and sufficient training, you are professionally quite unstable and exposed to any kind of calculation, especially when it comes to global statements.
I will refrain from comparing this with the professional competence of our politicians (ministers) at this point.

....With a natural stone heating system, the ventilation heat losses play absolutely no role.

Almost Nobel Prize-worthy. Ventilation heat losses are always present, depending on the building construction, (infiltration) (airtightness)! Suddenly not here? How miraculous?

...The system uses the walls, ceilings, floors ... bodies - for example, the (massive) walls store the heat for up to 2 hours ...

Why 2 hours, can it not only be 0.1 or 4 hours?

...- the room air is always equally warm or cold; depending on the point of view.

What is a point of view? According to which laws is the return temperature everywhere the same?

....You can imagine the mode of action similarly to a "sunbath" in the mountains. The ambient temperature is minus x° and yet you will hardly be cold.

Then stand in the radiation shadow and you will be damn cold.

....I have not sold this system for several years now, because I was tired of running against the walls of the big energy suppliers.

Incomprehensible, they would actually be pleased about high electricity consumption.

...In case of doubt, you will have to believe my information.

Hardly, since you have outed yourself as a professionally inexperienced saleswoman.

Best regards

Hello €uro,

It is bad when you operate in fields where you have no own and sufficient training; you are professionally quite unstable and exposed to any calculation, especially when it comes to global statements. I will refrain from making a comparison with the professional competence of our politicians (ministers) at this point

So you have no trust in engineering firms?

Almost worthy of a Nobel Prize Ventilation heat losses, depending on the building construction (infiltration), are always present (air tightness)! Suddenly not here? How marvelous?

What got on your nerves? I wrote: "In the case of a natural stone heating system, ventilation heat losses play absolutely no role." Not a word about them not occurring.

Then stand in the radiation shadow and you will get a... cold

Normally there is no shadow inside the house...

Incomprehensible; they would be happy about high electricity consumption.

At that time - 17 years ago - RWE earned significantly more money from gas than from electricity; insofar, their interest in a heating system running on the heat pump tariff tended to zero. Only today are their policy views beginning to change. Sooner or later, night storage heaters will be seen more often again, since RWE (all utilities) do not know where to put all the electricity from wind turbines.

Hardly, since you have outed yourself as a professionally inexperienced saleswoman.

Probably more than just one nerve...

Kind regards

Hello construction expert,

...So you have no trust in engineering offices?

Yes, provided they adhere to recognized technical rules (e.g. heating load calculation according to DIN 12831). Otherwise, I would have serious concerns

...What’s gotten on your nerves? I wrote: "In a natural stone heating system, ventilation heat losses play absolutely no role." Not a word that they do not occur.

No nerves, only half-truths or untruths annoy me. If, as you confirmed here, ventilation losses do exist but were not considered in the balance, a deficit arises. How is that compensated? The standard heating load (power) is completely independent of the heat generator and energy source!

40 kW/m² is close to a power plant

...There is usually no shade inside the house...

Then set up a partition wall, e.g. made of cardboard only, behind grandma’s tiled stove and stand behind it. The feeling of comfort is gone. Mr. Stefan Boltzmann has provided plenty of templates for this. You don’t have to reinvent what is already known, just apply it properly! In my own planning I sometimes also use electric heating (infrared) for limited peak load coverage when additional heat storage, for example, is not possible. Especially in heat pump systems, since it makes no sense to lower the efficiency of the entire system because of a few square meters of bathroom.

...RWE ...sooner or later night storage heaters will also be seen more frequently again, because RWE (all utilities) does not know what to do with all the electricity from wind power plants.

Are you seriously calculating with falling electricity prices? Let’s stay with the direct electric heating:

Building 15000 kWh/a energy demand (heating only); exact system dimensioning assumed:
Gas: €0.07/kWh; electricity: €0.19/kWh

Gas condensing boiler: 18750 kWh/a => €1313/a
Air heat pump: 4286 kWh/a => €814/a
Ground source heat pump: 3333 kWh/a => €633/a
Electric marble: 15000 kWh/a => €2850/a

Building 2500 kWh/a energy demand (heating only); exact system dimensioning assumed:
Gas: €0.07/kWh; electricity: €0.19/kWh

Gas condensing boiler: 3125 kWh/a => €219/a
Air heat pump: 714 kWh/a => €136/a
Ground source heat pump: 556 kWh/a => €106/a
Electric marble: 2500 kWh/a => €475/a

Significantly higher consumption is to be expected with insufficient system planning in some cases.
Overall, this is purely a consumption-side consideration, which must be supplemented by investment or capital service in terms of cost-effectiveness.
I cannot recognize an absolute or general “pro” for natural stone heating.

Best regards

Sooner or later, night storage heaters will be seen more frequently again, since RWE (all utility companies) doesn't know what to do with all the electricity from the wind turbines.

Hello Bauexperte,

or maybe rather day storage heaters – if you add all the photovoltaics to the wind energy.
So far, negative prices have already been achieved at the Leipzig electricity exchange at noon – not at night.

Regards
Micha

...So far, negative prices have already been achieved at midday on the Leipzig electricity exchange...

How can you as an end user benefit from this? Do you get the electricity for free or a bonus if you consume it?

Best regards