ᐅ Which heating system should be chosen for a new building?

Joedreck schrieb:
That’s new to me, could you maybe explain it via private message?

What exactly would you like explained?
Solar electricity isn’t exactly free.

A 7,000 euro solar system produces about 65,000 kWh over 20 years (depreciation), assuming 5% efficiency loss due to aging. That’s roughly 10.77 cents per kWh.

Then you have to add VAT. With a reasonable electricity purchase price of 24 cents (it can be cheaper but that’s difficult), that adds 4.56 cents.

So the cost per kWh is already about 15.33 cents.

Then there are ongoing annual costs. For me:
20 euros for monitoring
60 euros (12 x 5 euro VAT returns)
50 euros (proportionate tax consultant fees)

(In reality it’s actually more, since you need a PC, internet connection, antivirus software, etc.)

But realistically, for me, these add up to about 4 cents per kWh.

The lost profit must be taxed. Usually you can offset this with depreciation and other expenses (own time, tax consultant, computer, software) so it balances out to roughly zero.

That brings the total to about 19.33 cents per kWh for self-generated solar power.

Assumption: Neither panels nor inverter fail during the 20 years. In other words, the business risk is not yet covered. If you factor in a replacement inverter plus installation after 10 years (at current prices), that adds about 4 cents more. So we’re at around 23.33 cents per kWh.

So: I’m not trying to discourage anyone, but it’s important to be realistic. Self-produced solar electricity won’t be cheaper than grid electricity, and feed-in tariffs don’t even cover the costs.

That makes it even more surprising that many people have it. I thought that self-consumption would still be worthwhile. Well, learned something new again.

Self-consumption is more worthwhile compared to feeding electricity back into the grid. Whether photovoltaic systems are generally profitable is a different question.

However, it ultimately depends on the location and the associated yield forecast, and especially the investment itself, as shown by toxicmolotow’s calculation. If you purchase at too high a cost, you cannot expect a return.

You don’t always have to focus solely on the money.

For us, it’s just enough to break even, yet we decided to go for it anyway. I’m not expecting any return on investment.

You will be surprised by the declining efficiency of the collectors over the course of the year. After just a few years, their performance drops sharply. The simplest solutions are usually the best, and all that heat pump equipment consumes a lot of electricity.

My recommendation is gas or oil heating combined with controlled ventilation and heat recovery, plus a chimney.

No, I won’t be surprised about that.

1) Already taken into account.
2) Tell me something new.

Lately, I actually thought you were giving good advice. But right now, it’s turning into barroom talk, unless you want to support your statements with arguments or refute my posts.