Hi tinto,
I'm sure you're right but here there were a number of elements to consider (for thermal) that I had not come across before e.g. mains counter 400m away (voltage drop/3-phase needed?) and the rental contract with power supplier (ICP size), then diameter & number of cables from counter to house, etc. To go electric (no gas mains) for effectively unlimited h/w supply required investment of at least €2000 -- before switching on. The solar gear cost €2800 & with 300+ days of sun a year that also means virtually unlimited (& once installed, free) supply. Add to that smaller ICP (lower rental), monophase supply, thinner cables.....
Another point -- which hasn't been part of this thread & as an old man won't make any difference to me -- is the "green" aspect. We're assuming mains power will always be available but with nuclear fears & oil running out, should we? I'm told my panel will last 20 years so surely we should be pushing for these more sustainable solutions? And if we all do, the price of solar gear will plummet (think color TV). Of course, if something doesn't work (like solar gear in UK, I imagine), it doesn't work