There are mainly two types of solar collectors for solar water heating system:
Flat plate collectors and evacuated tube collectors.
In New Zealand under the conditions of the flat plate collector and vacuum systems can be equally effective use of solar energy, but also reduces the performance of how well as all of the components work together.
A flat-plate collector looks like a skylight. Absorb sunlight, it transfers heat to the water flowing through the collector plates (or heat transfer fluid).
A typical system would have about one house per square meter of collector. Vacuum tube consists of a series of glass tubes, 1.5 m and 1.8 m long, the inclination of the longitudinal axis from the ceiling on upward and downward. A typical system will have from about 5-10 per person in the house, then would be enough.
Under normal circumstances, the solar collectors placed on the roof. However, installation options are also available on the roof. In the ceiling of the solar collector is positioned on the ceiling, the manner similar to the sunroof. The solar collector may also be mounted to the level of the surface, which can reduce the installation costs and in some cases, the compliance requirements.