ᐅ Pellet heating system: yes or no?

This topic is currently circulating among us as well.
Pellet heating or alternative.
From what I have already heard from several people, pellet heating systems tend to be much more prone to malfunctions compared to others.
Then there’s the supply issue. Initially, pellets were made from industrial waste, but that is no longer sufficient today. Now, whole trees are being cut down to meet demand. To be honest, that also drives up the costs, especially when the wood has to be imported.
We all complain about deforestation, and now we’re heating our homes with that wood.
Sure, it’s a great concept, but I doubt whether it really helps protect the environment.
Besides, I’m really bothered by the huge storage tank. If you build without a basement, it takes up a lot of space.

So, we will most likely decide against a pellet heating system.

I am leaning more towards a ground source heat pump, but of course, that also depends on the cost. As an alternative, we are considering a gas condensing boiler combined with solar panels. So far, I have only heard good things about that.

That sounds good, but unfortunately, we are still at the very beginning of our planning.
We don’t even know yet if the bank will grant us a loan.
But maybe you could answer my question:
Can we achieve the KfW 40 standard with a gas condensing boiler combined with solar? The insulation and windows are designed for this.

How long is the offer valid?

If only the insulation and windows are designed for KfW 40 standard, achieving that level is probably very difficult. Unless you have a controlled mechanical ventilation system, etc.

At least, that is our own experience. What is the average U-value of the wall you are planning?

The primary energy factor for gas heating systems is quite unfavorable.