Design of Solar Dryer with Turboventilator and fireplace

1. Abstract Author has been using solar dryers for food processing, especially making Amla candy, since last five years. First drier is an innovative design with combined draught, natural and induced with fan. This dryer works well when fan induces draught. However when there is no power, the dryer works with natural draught but system under performs as the airflow is drastically reduced. In rural areas in Maharashtra Power cuts were increased to almost 14 hrs a day and practically no power is available to run fan during daytime when Sun is available. To counter this problem author has come up with a new design of solar dryer, which uses turboventilator for creating draught. Turboventilator runs on external wind and creates necessary draught and maintains good airflow through the solar dryer giving excellent performance. As the turboventilator works on outside wind only, no power is required and unit is truly a renewable energy gadget. The unit is also provided with a fireplace and bypass chimney. This facility permits the use of the dryer in night hours, cloudy days and also to accelerate the drying process when the Sun is available, by using some fuel like waste biomass. Turboventilator was preferred over Solar PV operated fan for the reasons of cost and possibility of operation at night or in cloudy period. Results of new solar dryers are very encouraging.