Gas heating new building - Is solar thermal necessary for hot water?

Thank you. Finally some action. But how do you know that? I searched on the internet and couldn't find anything....

And one of the two heating engineers just wants to sell me the ST with heating. He refers to the Energy Saving Ordinance

If he refers to the Energy Saving Ordinance, ask him where he got that from. Because he would have had to calculate the Energy Saving Ordinance certificate, which he definitely hasn't done, since he would need to know everything about your house for that. That is nonsense and a money-making scheme.

Alternatively, you can commission the creation of an Energy Saving Ordinance certificate, then you can prove in black and white what components you need for compliance.

I also suspect a sales argument. Now you have to know, when I look at my energy saving regulation calculation, which I don't fully understand, the building services engineering is just one parameter. The important thing is the windows, how many, how big? The fewer, the better it seems to me. Our house, for example, just barely passes the energy saving regulation. The solar system doesn't bring much credit. The whole thing is a kind of give-and-take calculation. And renewable stuff gives a lot of plus. Gas takes away. The whole thing is completely pointless and for me a reason to never choose this energy policy. It's just a subsidy program for heat pump specialists sponsored by the power company. Karsten

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And one of the two heating engineers only wants to sell me the ST with heating. He refers to the Energy Saving Ordinance

What is that supposed to mean? Signify? What is heating.?


Regards, Yvonne

Heating support

To realize ST with heating support, your flow temperature must be designed extremely low and the ST system must be designed very large. Domestic hot water is financially hardly ever worthwhile. The Energy Saving Ordinance concerns the primary energy demand. This can also be reduced by very good insulation or artificially calculated down by the ST system. I would try to insulate the floor slab well, as you never get access to it again, and insulate the roof/top floor ceiling thicker. This basically costs almost nothing extra in self-performance. Otherwise, only the walls are still possible, but that is not desired.

Alternatively, you can commission the creation of an energy saving ordinance certificate, then you can prove in black and white what you need for compliance regarding system components.

Exactly, and please not with the heating engineer mentioned, but with the energy consultant. Everything else is just guesswork ...