Whether it is worth fitting a Solar Water Heater to your home or, business is a complex question that is largely decided by the climate of your location and the type of system you would have to install. The heating energy of the sun is free but in colder climates with less solar heating the systems become more expensive and the payback of Solar Water Heater system and installation costs is much slower.
The Solar Water Heater systems installed in the warmer climates are less expensive to install operate and maintain while the drainback and anti-freezing pressurized systems used in colder climate are more complex, cost more and require more maintenance. The higher costs coupled with the fact that there is less heating available from the sun and more overcast days in the colder climates can severely reduce the speed of the payback.
In many locations of the US, Canada, and in Europe there are financial incentives often available in the form of tax credits and rebates to promote the growth of the solar industry. If you are considering installing a system you should talk to an installer about what you can expect to gain from a Solar Water Heating system. They should be able to explain to you how well a system can be installed on your home getting proper exposure on the collectors, where the panels would be located, how they would be attached to the roof, how shade from other buildings and trees would affect your system, the effects the system would have on your building structure, and the type and size of the system you will need. They should be able to tell you the installation costs and any financial incentives that are available to you for installing the system. So you can then make an informed decision on whether or, not you want to install a Solar Water Heater in your home or, business.