So I actually have experience with these in the north of Sweden - they are definitely more efficient in summer, but do provide some amount of hot water as well in winter on days with clear sky (of which there are few).
On the topic of using this for heating in the Mediterranean - I don’t think that’s where you want to invest, installing underfloor heating in one of those houses. That will cost some serious money. It’s probably wiser to spend it making the home less prone to get cold/hot using insulation in that case. I will admit to being out of my depth when it comes to optimizing buildings for hot climates though
NIB@lemmy.world 1 month ago
Pretty much all houses in Greece have this and no, it is only good for the summer or sunny days. But still it is a no brainer, unlimited free hot water during the summer and limited free hot water during most days.
The tricky part is calculating whether it was sunny enough(during the winter) to produce enough hot water for your shower or if you need to turn on the electric water heater.
Some greeks pre-emptively turn on the electric heater for 15-30 mins, other more financially stressed greeks prefer to gamble.
Evotech@lemmy.world 1 month ago
Couldn’t you just have a thermostat on the tank
Threeme2189@lemmy.world 1 month ago
You could, but the idea is to only heat water when necessary (there isn’t enough hot water and you need to take a shower), keeping it hot all the time is wasteful.
GissaMittJobb@lemmy.ml 1 month ago
Running a thermostat 15-30 minutes before the hot water is needed would only consume electricity if the water is not already hot. You probably want a well insulated accumulator tank with one of these systems to not lose the energy produced as well.
Tobberone@lemm.ee 1 month ago
Where I’m from the heating utility was turned on last week and will remain on until April. To me, running a heater for 30 minutes/day during winter seems acceptable:D