Gas heating + solar thermal energy

Thank you for the lively participation in the thread. Although there is a natural gas pipeline from the local gas supplier at the property boundary and it will probably be the cheapest option to install a gas heating system compared to everything else, we are still considering using renewable fuels. We are relatively young and (God willing) will live in the house longer than the aforementioned 20 years. No one can say today how gas prices will develop by then. I also cannot say yet what our heat demand and heating behavior will look like. Of course, the heating system installed depends on the type of house construction. Nevertheless, I want to already familiarize myself with various systems and weigh the pros and cons. Just wanted to know if it basically makes sense to disregard the gas line and, for example, install a pellet heating system. PS: The basement probably won’t be built either, so we would then rely on a pellet storage tank. The question is whether this effort is even worthwhile and, if so, how quickly the costs would amortize compared to a gas heating system... A difficult question when you don’t know the construction project. Still, please provide a few pointers, comments, etc....

Of course, the heating system installed depends on the type of house construction. Nevertheless, I would like to deal with different systems now and weigh the advantages and disadvantages.

How should that be reliably possible if demand figures are not available?

... A difficult question when you do not know the construction project. Still, please give a few hints, comments, etc....

Exactly, guessing without a reliable background. In my opinion, not a sufficient basis for a long-term investment decision.

Regards

Thank you €uro, it helped me a lot. I want to get information and not decide and invest immediately.

Hello €uro,

I see it differently ;-)

Of course ;)

Well, then bring on the results, investment effort (capital service for this) / actual harvest. I’m curious ;-)

Posting all of that here would exceed the scope of this forum and the forum operator would stone me. Just go to the Sonnenhaus Institute’s website; there you will find all the information – including about the investment – on various new buildings. I have already written to Prof. Leukefeld today – I attended one of his lecture series last Wednesday – and ordered the slides from the lecture. When I have them, I will provide the actual values.

Completely wrong. The more thermal energy has to be stored, the less economical it is!

Your perspective, and that is yours to have.

Gas condensing boiler + connection costs are of the same order compared to, for example, an air heat pump ;-)

I do not contradict that at all, only the connection costs (after installation) for gas condensing boilers and solar thermal will clearly favor solar thermal in the medium term future.

Kind regards

... When I have them, I will provide the actual values.

I am looking forward to it.

... only the connection costs (after installation) for gas condensing boilers and solar heating will be significantly in favor of solar heating in the foreseeable future.

Well, then please support your thesis with comprehensible numbers/facts!
In the last case regarding the solar thermal system, neither you, nor your nationwide MEP planner, nor the OP contributed anything towards clarification. In my assessment: pure "empty talk!"

Best regards

Hello €uro,

“smart” as always ...

I am looking forward to it.

I hope I remember. So that the time doesn’t seem too long for you, I searched the internet for "builder information" on solar houses. I don’t want you to accuse me of manipulation – I know neither the builders nor had any other contact with this project; I removed the information about the provider because it is secondary.

Front view with south orientation



Two stories with 11.00 m width and 9.50 m depth

“10.06.2008

At last we have decided to build a solar house.
We will have our house built completely ecologically. This means that this special house works without oil heating, gas, or heat pumps. It is a house built stone by stone with extra insulation on the exterior walls. Furthermore, the house body is oriented towards the south and has a large window front on this side. Also (...) we are getting a water tank that holds 7000 liters and will be about 4.60 m high. This tank is heated by solar collectors on the south side of the roof. If the output of the solar cells is not sufficient during the winter months, additional heating is provided by a wood gasification stove. This stove has two advantages: a beautiful chimney is automatically installed in the living room and it only requires about four cubic meters of wood (1 cubic meter corresponds to 1 Ster) due to the special combustion. This stove does not let the wood go up in smoke but lets it smolder and thus produces more kWh than normal combustion. Additionally, the stove has a heat exchanger in the chimney to recover the residual heat from the exhaust air.

18.08.08

Today the energy saving certificate according to the Energy Saving Ordinance arrived by mail.
The allowable annual maximum value according to the Energy Saving Ordinance would be 113 kWh/m².
The calculated value for our house is 9.48 kWh/m². Amazing!!! Super.

17.11.2011

We are now in the third year in the house and (...) I want to mention one thing, we have heating costs per year of about 220 EUR for hot water and heating. This means we need about 1.1 tons of wood per year to bridge the missing sunny days. I am absolutely thrilled about that. The electricity costs are also reasonable. Despite pumps and so on, we have an average annual consumption of 2900 kWh. (3-person household, all employed) Really great!!!!”

I am convinced that laypeople can classify these – freely retrievable – entries from the construction diary of a solar house.

In the last case regarding the solar thermal system, neither you nor your nationwide TGA planner (...) contributed anything to clarification. In my assessment: Pure “empty talk!”

I have deliberately taken my time to answer until today; yesterday I probably would not have been so careful in choosing my words.

It is one thing if you accuse me of “empty talk,” quite another when you accuse a reputable partner yourself. This TGA planning office is not a small outfit that – because of price discussions with potential clients – falls back on statements like “A good planning/dimensioning is by the way very easy and inexpensive to get ;-)”. They basically offer integrative planning using simulation techniques to optimize energy use, overall technical planning considering innovative, regenerative, and alternative energy forms, etc. Their reference list is impressive and they certainly wouldn’t be represented with 5 locations in Germany if they were “empty talkers.” So please be so kind and limit your scorn to me!

In the end, I could – comparable to your approach here on the HBF – also “bombard” you with slides; whether that is productive is another question. Recently you answered a user’s question at one point – “Since various vendors offer identical houses with different kfw values, there should be numbers available for this as well. It’s a shame that none of you know them,” with “I know them from individual construction projects. However, they are not generalizable.” Prior to this sentence, you offered your commissioning, but you never considered publishing the values – even if only selectively.

You know that I appreciate your answers here on the HBF in principle, but sometimes you too should wait a day before responding ...

Kind regards