Er, Mr Subaqua, I'm not disagreeing with you so I'm not sure what that's about?
I don't have a hot water tank system, so without entirely replumbing my house with a new water management and heating system aren't in a position to benefit from a solar water heater.
Not aimed at you.
Solar PV has Been made out to be the bees knees but it isn't one size fits all sadly.
You never get told that the efficiencies are calculated at a specific temperature range. Out of the temp ranges then the efficiencies drop right out. In the summer at peak sun and peak heat the panels can be at less than 50 % efficient.
The sellers bang on about south facing giving the best results but there is evidence that if I could get to on the ipad I would post , that east and west facing can give just as good results as the panels don' t get far out of the temperature range so efficiencies do not drop.
Still if you know what you get yourself into then go for it.
There are still ways to put storage tanks on combi systems so never rule that out. Good for you for thinking about energy reduction even if it is for the smugness