Heating offer comparison - Please share your experiences

But I can generate electricity myself

(1) Depending on your personal income situation (tax rate, business), self-generated electricity is NOT free, but must be taxed with income tax and sales tax. Have you calculated that precisely and fairly? How expensive is the kWh of your own electricity just due to taxes? What are the provision costs from purchasing the photovoltaic system (total yield/total costs including depreciation/maintenance of the system)?

(2) Especially in winter, most photovoltaic systems owned by homeowners definitely do NOT have enough capacity to avoid buying electricity. But in winter, the performance factor of heat pumps is particularly unfavorable.

Rough rule of thumb: A photovoltaic system produces about 1/8 of the output in winter (Nov-Feb) compared to summer (Jun-Aug).

A photovoltaic system must be unrealistically large to generate all the electricity for the heat pump even in winter. Furthermore, the instantaneous consumption of heat pumps is quite high and cannot be covered directly by the photovoltaic system in winter.

So I have a maintenance contract for my gas condensing boiler system. Including parts and emergency service.

Then the contract might be a bit excessive? You don’t really have to "insure" emergency service in advance and pay extra for it. Maybe you should reconsider your maintenance contract.

But yes, a lot of abuse is committed with maintenance and customers are ripped off. You have to be very vigilant and negotiate well.

In winter, when the heating should be running hard, rather not. At least not on the roof....

That is correct, but this is an annual calculation with self-consumption and feed-in!


Heat pumps can already be obtained for € 4000,- / not all devices cost € 10,000 or more!

Whether a heat pump pays off with/without purchased electricity will always depend on how the system is planned or
the required consumption and how prices for gas/electricity develop.

Then maybe the contract is a bit exaggerated? You don’t have to "insure" emergency service in advance and pay extra for it. Maybe you should reconsider your maintenance contract. But yes, a lot of abuse is done with maintenance and customers are ripped off. You have to be very vigilant and negotiate well.

OH yes! The contract is too comprehensive. Unfortunately, it was only offered that way. Unfortunately. However, a comprehensive maintenance contract was mentioned. I have that. And it is expensive. However, I still doubt that it will be more expensive for a heat pump. Because basically, with a heat pump, you just wipe over it once, check the pressure, and that’s it.

Modern condensing boilers are very complex to clean. At least most of them. And that annually.

Personally, I also trust myself more to maintain a heat pump than a fossil fuel heating system. Especially gas. If the pressure on the heat pump drops, I can call the professional. With gas, I prefer to keep my hands off.

By the way, this is not an argument in favor of heat pumps. I would always want to make the decision individually.

Heat pumps can already be obtained for €4000 / not all devices cost €10,000 or more!

Yes, that is correct. If you rely on very inexpensive heat pump models, then it can be worthwhile. The question, however, is whether these devices provide adequate comfort, e.g. noise level at the installation site / performance during high heat demand in cold winters / overall hot water comfort, and of course how long these cheap ones really last. I am already bothered by these 300-liter tanks. Space requirements, incubation of germs, standby losses. And the good systems with fresh water stations are then significantly more expensive again.

Whether a heat pump pays off with/without purchased electricity will always depend on how the system is planned [ist]

Of course, a lot depends on the planning, but ultimately this "it depends on the planning" is often just window dressing in practice. As I said, anyone planning something like this should definitely also consider realistic, binding offers for maintenance and not ignore the taxes on self-generated electricity. Two points that are unfortunately often forgotten. Annual performance factors also obscure the special demand in particularly cold winters. In fact, many then mostly heat with purchased electricity.

By the way, this is not a pro heat pump argument. I would always want to make the decision individually.

I admit that I tend to argue against heat pumps -- because, with very few exceptions, the noise alone bothers me massively. But also because in very cold winters, heating is practically always done with purchased electricity and because the hot water comfort is almost always inadequate, especially for more frugal builders.

However, I still doubt that a heat pump will be more expensive

Well, I can’t make an absolute statement either, but what I have heard so far about maintenance contracts regarding heat pumps is not encouraging. But yes, as always, it depends on the individual case -- I just wanted to say here that everyone should get a binding offer so they know where they stand. At least don’t forget to take this into account.