Development of a Solar Drier for Domestic Applications

The solar drying system utilizes solar energy to heat up air and to dry small scale domestic produce like grain, omena, vegetables etc. This is beneficial in reducing wastage and hence preservation of agricultural products as well as increasing affordability by the local population who naturally cannot afford the higher cost of mechanical driers. This study presents the design, construction and performance of solar grain dryer. In the dryer, the heated air from a separate solar collector is passed through a grain bed, and at the same time, the drying cabinet absorbs solar energy directly through the transparent walls and roof. Tests carried out on the drier showed that the temperatures inside the dryer and the solar collector were much higher than the ambient temperature during most hours of the daylight. The temperature rise inside drying cabinet was up to 24oC (74%) for about three hours immediately after 12.00h (noon). This indicates better performance compared to open sun drying.