THE COMPONENTS
To install solar hot water, you will need more than just the solar panel. Here is a brief list of the other parts of the system.
This is how the solar energy is transferred to
heat your water. The two main types of circulation are active and
passive.
Active circulation employs a pump to move the fluid in the pipes.
Passive circulation uses the natural properties of heat rising to move
the fluid.
In colder climates, you need to be able to drain the pipes to prevent
them from freezing in cold weather. There are several types of systems.
The most reliable is an indirect drain down system.
An indirect system is where another fluid is used in the pipes, then
the heat is transfered to your hot water. These are also known as
'closed loop'
systems, because the fluid in the tubes never mixes with your hot water.
So in an indirect drain down system, the fluid is drained every night,
preventing pipes from freezing and splitting.
This varies. The storage tank for solar hot water
is usually bigger than a normal hot water cylinder. The size is
specific to the system, so it's best to follow the specifications.
Important things to consider here are that the storage tank is well
insulated to prevent heat loss. If you can locate your tank
close to where hot water is being used - ie the bathroom and kitchen,
that will also prevent energy loss from the pipes.
Most solar water heaters can supply 50-80% of your household needs - more in summer, less in winter. Because of this, most heaters need a gas or electric backup system.
One issue with solar hot water collectors is controlling the heat of the water. A controller limits the temperature that at which water enters your hot water tank. It has a sensor that reads the temperature, and mixes in cold water to keep it at a constant heat. The usual usual water temperature is between 120 and 160 degrees.
It is important to have a qualified plumber and electrician install your solar hot water system.
Related Links:
Types of Solar Hot Water Systems
How much Solar Energy for Your State