There is something very special about solar hot water heaters - they work. Okay, all renewable energy technologies work - but who really wants the windmill with thirty yard wings in the backyard just to save a few bucks?
Renewable energy - energy that we can keep on using, not like coal, gas and oil which we will sooner or later exhaust - is a great idea in theory. The trouble is that much of it is not easily adaptable to home use. Windmills need to be big to make much energy, waterfalls need to be high and close to the house for hydro electricity.
No so for solar hot water. whether it is solar pool heaters you are interested in or providing hot water for the home, solar can do the trick. It is the most practical of renewable energies.
So what are the problems. Well first you do need sun. But a surprisingly large number of homes do have enough sun. The next thing you need is solar panels. These are just big black panels that the water runs through while it gets heated by the sun. And here is the second objection - where do you put a big ugly solar water heating panel?
On the roof is the classic solution, but you need to be sure that the installer knows what he or she is doing. These things can weigh plenty when full and they expand and contract due to the heat. A badly installed unit can cause your roof to leak.
But these are not reasons to put off getting the solar heating advantage. Plenty of free running hot water, helping your wallet and, more importantly, helping preserve resources for the generations to come.