ᐅ Air-to-water heat pump combined with photovoltaic panels or pellet heating with solar thermal system

Hello everyone,

I am about to start a construction project.
Single-family prefabricated house with a basement.
Heated area approximately 350 square meters (3,767 square feet).
Two adults and currently two children, possibly a third child to follow.
A controlled ventilation system is planned.
Putting aside the initial costs of the heating system,
which option will be more cost-effective in the long run for heating expenses?
An air-to-water heat pump possibly combined with photovoltaic panels?
Or a pellet heating system combined with solar thermal?

For your information, in my current quote the air-to-water heat pump including photovoltaic system costs 37,000, with the photovoltaic system priced at 20,000.
The pellet heating system including solar thermal is quoted at 21,500.

What do you think the ongoing heating costs will be for the house approximately?
What do you recommend?

I don’t like solar panels; the cost-benefit ratio isn’t good. I prefer pellet heating combined with photovoltaic systems. That’s what I have installed myself.

Depends on the house... which insulation?

Does the pellet offer already include the tank and subsidies, etc.? Have chimney costs been considered?

For an air-to-water heat pump of this size – I estimate roughly €90 per month;
€20,000 photovoltaic system corresponds to about 13 kWp – approximately 16,000 kWh – without knowing the exact location, roof pitch, and other factors. With 20% self-consumption, this means about €66 per month in electricity savings and €128 from feed-in tariffs, adding up to €2,328 per year.

Depending on your budget – and especially on how many kWp you actually get for your €20,000 – I would either install just an air-to-water heat pump without photovoltaics or include it as well.

Toxicmolotow clearly explained that photovoltaic systems only generate power when the air-to-water heat pump doesn’t need it.

So, if you want an air-to-water heat pump, then a ventilation heat recovery system (VHR) without photovoltaics, etc. is the way to go—unless you’re an individualist with extra money to spend.

Alternatively, you could choose a completely different heating concept with pellets or gas.

Well, I see it differently. Especially with an air-to-water heat pump, photovoltaic panels do make sense. Photovoltaics help offset part of my energy costs. Even in winter, photovoltaic systems still produce reasonably usable electricity. Using the SMA energy manager, I can increase my self-consumption to up to 50%. At that point, photovoltaics really start to make a lot of sense. Later on, you can add a battery storage system. I would only consider an air-to-water heat pump today if photovoltaics are also part of the plan. In that case, you should also take the buffer tank into account. Without photovoltaics, the buffer tank doesn’t really make sense, but with it, it definitely does...

Some time ago, I heard a radio program where an expert from the Fraunhofer Institute was interviewed on this topic. He advised against pellet heating systems. It is no longer true, as was often claimed in the past, that pellets are made from waste materials. His recommendation was to use an air-to-water heat pump combined with a photovoltaic system on the roof. A friend of mine has a pellet heating system and told me that it creates quite a bit of dirt and dust when the pellets are delivered.