Solar Installation Basics


Installation Basics
When choosing a solar collector, it is important to select the correct size. To find out what size collector you need please click here. Once you have determined what size of collector maybe suitable for you, then next question is where to install it.
Direction and Angle of Installation Decision
The angle and direction of installation is also very important because it will effect the efficiency of the solar collector. Certainly you want the collector to absorb the maximum amount of sunlight every day and the whole year. General speacking, if you are in the Northern Hemisphere, then the collector should face South while if you are in the Southern Hemisphere, then the collector should face North. You can refer to the diagram below.
which angle you should fix the collector depends on the latitude of your location. For example:
- Melbourne, Australia has a latitude of 37o South - the collector should be faced to north at a 37o angle.
- London, UK has a latitude of 51o North - the collector should be faced to south at a 51o angle.
You do not need to be too care about the mounting of the collector at an exact angle. If your roof angle is within 10o+/- of your desired angle you only need to mount the solar collector flush against the roof surface. The extra troubles of adjusting the collector to a precise angle are not guaranteed because it won't affect too much on improvement of efficiency.
Seasonal Changes in Heat Output
How to prevent excessive heat output in summer
If you are using the solar collector for space heating as well as hot water products, or if you just want a large solar contribution, you need a system which will greatly surpass heat requirements in the summer. Generally there is no heating required in the summer, cooling is contrary to it. But unfortunately, solar cooling for domestic applications is noteconomically available at present, so how to deal with the excess heat? But the excess heat can be used, if you have a swimming pool or spa. Turning off the pump, in order to prevent the high pressure and temps, and large volumes of vented steam from affecting the normal working of collector. 
If you do not want to use the excess heat, then adjust the angle of the collector, it can help to reduce summer heat output. As it can be seen by the above diagram, the sun is below the sky during the winter and but high in summer. Solar smart house is designed for taking great advantage of this principle by facing great area ofNorth or South (depending on your location), allowing maximum absorption of sunshine in winter, with large eves or veranda to block out the sunshine in summer.
By increasing the vertical angle of the collector for about 20o more than the location's latitude (ie. 60o instead of 40o), greater heating performance will be experienced in winter. This is because the collector is "facing" the sun directly(perpendicular - longitudinal angle). Due to the higher location of the sun in the sky in summer, the collector will be around 40o from perpendicular so the heat output will be reduced as the collector is not fully "facing" the sun. In this way, it can reduce peak summer output efficiently, so as to solve the problems associated with excessive summer heat production.
The above photo shows an ideal installation angle that optimises the winter, spring and autumn heat output, at the same time reduce summer output into minimal. The high angle not only increases the exposion of sun in winter, but also allows the sunlight reflected off the snow to be absorbed. In the summer when the sun is high in the sky ,then the exposed surface area is small, especially the overhanging roof would partially shade the sunshine of the collector. In areas without snow fall (and a latitude range of 30-40o) it would be suitable for a lower angle than what shown above.
Please note: For the Sunflower solar water heater, the optimal angle range of heat pipe performance is 20-70o. Although the latitude of your location may less than 20o, the basic installation guideline should be persisted. Horizontal angles of +/- 5o are acceptable and may be suitable if the manifold needs to be drainable (end port models only).