Although, it is easy to realize that the temperatures prevailing in the convective±radiative dryer
are lower than that in the solar boiler dryer. This is due to the eect of air passing through the
waste, yet the eect of high mass ¯ow rate of air which allows more moisture to be carried out
counteracts such a drawback, thus giving two designs of solar dryers comparable in their
operation. The superiority of either can be deduced from the results obtained from their
operation under the prevailing conditions described in this paper. It is also worth mentioning
that the cost of the convective±radiative dryer is estimated to be about 15% less than that of
the boiler type.