A solar water heater will save you big bucks on hot water. Look at solar water heating options if energy efficient hot water is on the list of green upgrades you're considering for your home.
Over a 20 year span, using a solar hot water system can displace over 50 tons of carbon dioxide that would otherwise have been released into the atmosphere.
Approximately 30% of your household energy bill represents water heating costs. More if you have a heated swimming pool.
Taking your water heating needs off the grid removes pressure from your existing energy infrastructure.
As demand for energy increases in municipalities, existing infrastructure can become overburdened and unable to keep up with demand. Some municipalities have adopted a routine of rolling brownouts (times of the day where energy is rationed) to avoid having to go the the considerable expense of expanding their facilities and their output potential.
Building new power plants to address the demand is very expensive not to mention a move backward when, internationally, the mandate is to clean up our energy act. It's less expensive and more progressive to encourage residents (with incentives and rebates) to switch to clean, green, energy sources. Check for local and federal incentives in your area.
Constructed of more expensive materials (copper), glazed panels are more durable and can be coaxed to function in below freezing temperatures. They're also the more expensive choice.
Sunlight passes through the non reflective glazing panels and collects on a dark absorber plate behind the glass. Tubing is looped back and forth under the glass next to the dark plate and through the tubing circulates air, water or an antifreeze solution. As the fluid or air in the tube warms, it moves off to a well insulated storage tank or is used immediately.
The pipe is usually coiled or looped into a compact unit that is placed in a sunny area preferably on a black surface (the more heat, the better). Water fills the pipe and the heat that the black pipe collects is then transferred to the water.
The hot water can be used directly from the unit or directed to an insulated tank for storage.
If the collector is situated on a roof or other elevated structure the hot water can be accessed by gravity (another free source of green energy).
In climates where temperatures never dip below freezing an unglazed solar water heater will probably meet all of your requirements.
Here's a great video on assembling an unglazed passive water heater. Minimal materials are needed to assemble this easy DIY solar hot water system.
Use it for your home water supply or to heat a swimming pool and start saving money right away.