Year round potential of greenhouse as a solar dryer for drying crop produce

Abstract

An experimental investigation was carried out to determine whether sufficiently higher temperatures are available inside the greenhouse for drying crop produce. The greenhouse air temperature was calculated using a steady-state model. Calculated and measured data compared well for different months of the year. The maximum temperature gain of about 25.1°C, 21.4°C and 14.5°C were obtained during May, September and December, 2015 respectively. However, during September the minimum gain was 7.5°C. The maximum temperature inside a bare greenhouse enclosure reached above 64°C. The model can also predict the relative humidity inside the greenhouse enclosure. The inside relative humidity varied from 13.8 to 35.2% in the year 2015 during 10:00 h to 16:00 h Validation of observed and predicted values of greenhouse temperature was carried out with higher R2 values (0.991 to 0.999). The model can also be used to modify the design of the greenhouse according to the optimum temperature required.