If you’re refurbing or building new, what is the cheapest way to produce hot water?
There have been a few discussions of various technologies individually, but it strikes me that there must be a “best” answer for a typical house in the Irish climate.
Air source heat pump?
Ground source heat pump?
Solar water heater?
Solar PV + immersion?
Grid + immersion? (Surely not!)
By “cheapest” I mean TCO over the life of the equipment, including energy inputs to run the system (pumps, etc). Ignore time-value of money. Assume a typical house with a grid connection etc.