Hello,
we are planning to build a detached house with about 200 sqm (2,150 sq ft) of living space.
The heating system will be a gas condensing boiler.
In the living and dining area, there will be a water-bearing stove.
And photovoltaic panels on the roof.
Our energy consultant said that if we want KfW 70 (a German energy efficiency standard), we need to install solar thermal panels on the roof instead of photovoltaic panels. But I would actually prefer not to do that.
Now to my question: Does solar thermal for hot water provide the same benefits as photovoltaic?
On the one hand for the KfW application,
and on the other hand from an energy perspective? And economically?
Thanks for your experience and input.
Best regards
we are planning to build a detached house with about 200 sqm (2,150 sq ft) of living space.
The heating system will be a gas condensing boiler.
In the living and dining area, there will be a water-bearing stove.
And photovoltaic panels on the roof.
Our energy consultant said that if we want KfW 70 (a German energy efficiency standard), we need to install solar thermal panels on the roof instead of photovoltaic panels. But I would actually prefer not to do that.
Now to my question: Does solar thermal for hot water provide the same benefits as photovoltaic?
On the one hand for the KfW application,
and on the other hand from an energy perspective? And economically?
Thanks for your experience and input.
Best regards
Why is it confusing? Because it doesn’t make economic sense. What are you trying to save with just 50 € heating costs per month?
You might pay another 15 € per month for hot water... Even if the system costs only 2,000 € including installation, that means 11 years...
3%... I hope the additional water piping didn’t cost more than 270 €... that’s the contribution to energy generation over 15 years.
You might pay another 15 € per month for hot water... Even if the system costs only 2,000 € including installation, that means 11 years...
3%... I hope the additional water piping didn’t cost more than 270 €... that’s the contribution to energy generation over 15 years.
Why are you worrying so much about whether photovoltaic or solar thermal systems are cost-effective when you’re already spending several thousand euros extra to install a wood stove with water heating alongside the gas condensing boiler?
That’s not really about efficiency or cost-effectiveness, is it?
You can achieve KfW 70 standards without solar thermal, but if that’s not working even with the stove mentioned above, in my opinion you should reconsider the entire concept (insulation?).
If you don’t want insulation suitable for KfW 70, I would rather advise you to forget about KfW altogether, so you don’t end up with a messy compromise.
That’s not really about efficiency or cost-effectiveness, is it?
You can achieve KfW 70 standards without solar thermal, but if that’s not working even with the stove mentioned above, in my opinion you should reconsider the entire concept (insulation?).
If you don’t want insulation suitable for KfW 70, I would rather advise you to forget about KfW altogether, so you don’t end up with a messy compromise.
There are so many factors involved in insulation and similar aspects that I wouldn’t rely on a general, unchecked statement from your building consultant. However, as a layperson, I’m not really able to evaluate it either.
Ask for the calculation for the building envelope and try searching online for a forum specializing in building services engineering. They are knowledgeable and helpful with these kinds of questions and will probably be able to assess it better.
Ask for the calculation for the building envelope and try searching online for a forum specializing in building services engineering. They are knowledgeable and helpful with these kinds of questions and will probably be able to assess it better.
Similar topics