Gas heating without solar thermal?

Energy Saving Ordinance and KfW are two completely different things.

These are all specifications regarding the Energy Saving Ordinance-2009, which still apply to you.

I would be interested to know what your price comparison showed. I would strongly guess that without solar thermal, it is so much cheaper that the low consumption costs with a solar thermal solution are not enough to amortize the additional costs of solar thermal in the first 20 years.

But well, the Energy Saving Ordinance-2009 is now passé. I am not familiar with the new regulations, I suspect that now it is no longer possible to have a gas heating system without solar thermal. jx7

Hello jx7,

so I need a proof of the Energy Saving Ordinance and not a KfW certification? Even if they are two different things, they are somehow connected.

The solar package costs about 3,100 EUR whereas the additional cost for the KfW 70 certification is 1,650 EUR – and I am still not quite sure whether I even need that or not.
Maybe there will be some additional costs for insulation, but even if it were cost-neutral, the extra insulation should require much less maintenance / have less risk of failure than the solar package.

Therefore, the question arose for me, how exactly the -15% are to be proven.

Best regards

The methods for the [Energieeinsparverordnung]-verification are actually the same as for the KfW-verification, namely a calculation of the two key figures. Nevertheless, our energy consultant wanted 500 € more if, in addition to the [Energieeinsparverordnung]-verification, a KfW-70-verification had to be carried out because supposedly more formalities need to be done (including checking the correct implementation of the measures, construction site inspection, etc.). The KfW-55-verification is even more complex.

An [Energieeinsparverordnung]-verification must be carried out regardless; the costs are incurred no matter whether built with gas plus solar thermal or with gas and the 15-percent rule. The [Energieeinsparverordnung]-verification may already be included in the house construction contract.

3,100 € (net/net?) for solar thermal seems very cheap to me, I would have expected around 6,000 € (see heating comparison page).

An energy saving ordinance certificate must be provided anyway, the costs occur regardless of whether it is built with gas plus solar thermal or with gas and the 15-percent rule. The energy saving ordinance certificate may already be included in the house building contract.

Thanks - 3,100 EUR gross for material costs alone. We will definitely try the 15-percent rule, which is why we’ve done everything to submit the application still in the old year. The energy saving ordinance certificate is included in the price anyway as you say, so the balance tips even more towards the 15-percent rule.

The new rules no longer allow just installing a gas heating system. From my point of view, solar is not worthwhile, even if no maintenance or repairs are necessary. So we’d rather do without it altogether.

Best regards

KfW 70 certification costs around 1,650 EUR – and I still am not entirely clear whether I even need it or not.

If you want to take out an efficiency loan from KfW (arranged through your bank), then you need the KfW certification (you can find details in the information sheet for the respective KfW loan program). If you do not take out an efficiency loan, you do not need this proof. The additional cost of 1,650 euros should be compared with the interest savings of an efficiency loan compared to a normal loan. In hindsight, I might even proceed without KfW financing.

I wanted the complete package from a single source right from the start, not split over 2 banks, 2 loans, senior, subordinated... I wasn't interested in all that hassle anyway, just to get a few tenths cheaper on 1/5 of the amount. The fact that the interest advantage is practically eaten up again by the additional costs is another factor. So I thought, better "keep it simple."