Compared with traditional water heating system, solar water heating systems usually seems cost more to buy and to install. But, in the long run solar water heaters can always save much more money for you.
Then, how much money solar water heater can save for you? It depends on the following items:
1. The performance of your system
2. The geographic location and solar insolation at your place
3. Financing and incentives which is workable and available
4. The cost of conventional fuels (Such as gas, oil, electricity and so on)
5. The cost for backup water heating system, if you own one.
On average, if you buy and install a solar water heater, the costs of your hot water heating bills should drop 50%–80%. Also, because the solar energy is free, you don't need to worry about conventional energy shortage and price increasing.
So it would be a wise choice to use solar water heating system.