As for Austrian and German supply's how do you run a whole house on 25 amps supply? In my house our peak load is about 45 amps admitidley only for maybe 10 mins a day and not everyday in fact only 2 or 3 days a week normally
A house will usually have 3-phase so assuming mainly 1-ph loads you have 75 A available at 25 A per phase. In a flat with gas-fired combi boiler and gas cooker you'd be hard-pressed to exceed 25 A single-phase, I've never managed to do that. I suppose you could try running washing machine, dishwasher and kettle at the same time but that's a rather rare occasion and both washing machine and dishwasher cycle the heating elements on and off.
Now in Italy with their 15 A 1-ph supplies it gets scary... electric oven and immersion heater are enough to plunge the house into darkness, so don't shower while something's in the oven!
I do have to say I'm a bit wary adding an electric oven to the 25 A 1-ph supply we've got here (there's been talk about that lately because the new gas oven is much worse than the old one even though the door of the old one had to be wedged shut with a wooden stick held in place by a half-open drawer) but if we avoid running oven and dishwasher at the same time we could even do that I guess.