= Overview - =
- Picture http://www.daviddarling.info/encyclopedia/S/AE_solar_air_heater.html
Solar air heaters are systems that collect solar energy and transfers the heat to passing air, which is either stored or used for space heating. The collectors are often black to absorb more of the sun's energy and a conductive material, often metal, acts as a [[Heat Exchangers|heat exchanger]]. There are many different designs and systems may include fans to increase the flow rate of air. Alternatively, a passive collector can be built whereby the hot air rises and draws fresh air through the bottom. Fans can often increase the performance of the system, but require additional parts and adds complexity. Solar air heaters can compliment traditional indoor heating systems by providing a free and clean source of heat (after initial costs). While clouds effect the energy output of the system, the metal will store energy on a hot day and will reduce the impact of momentary cloud cover. To achieve best results, the system should be unshaded and facing the general direction of the sun (south for the northern hemisphere, north for the southern hemisphere) <br> In the UK, 40% of all energy consumption was dedicated to space heating. This percentage is the largest component of energy use and can be reduced by simply using solar air heaters as a means of enabling the sun to passively heat our in door areas without consuming the Earth's finite resources. [[Image:UK_Energy_Breakdown.jpg|left|450x280px|Breakdown of energy use in the UK]]<br>
How to calculate energy gain and efficiency.
= Materials =