Solfångare : Konstruktion och utvärdering av prestanda

Sammanfattning: Energy supply and impact on the environment are two main problems that the world faces right now. During a longer period of time fossil fuels has been used as primary energy source. The use of fossil fuels has contributed to large emissions of greenhouse gases and global warming. With an increasing population the need of energy increases as well, and therefore, more energy will be needed that doesn’t affect the environment negatively. To achieve this, the use of fossil fuels should be minimized and the use of renewable energy recourses should increase. Solar collectors uses solar energy, a renewable recourse, and this report is about solar collectors in brief and how a simple solar collector can be constructed to be as efficient as possible. Initially the different types of solar collectors and systems are researched. Most discussed are flat plate solar collectors and evacuated tube collectors. Other mentioned collectors are air-collector, pool-collector, compound parabolic collector, parabolic trough collector, Fresnel reflector, parabolic dish reflector and heliostat field collector. The constructed solar collector is a flat plate collector and the used material is partly reused and recycled to minimize the impact on the environment. The solar collector consists of corrugated plastic, hose, plasterboard and a plastic cover. The test solar collector is constructed and tested at Tenerife but are (supposed) to be used at an education center in Cameroon. The test solar collector has an effect of 167 W and an efficiency of 65 %. The efficiency is as good as the ones on the market, which depend on the thin corrugated plastic used as absorbator. For the test conditions a heat transfer analysis shows that the heat loss coefficient is 14,8 W/m2. The test solar collector can be improved in different ways and some of them are listed in the report. Construction manuals are available in English and Swedish.