Technical and financial feasibility of a solar dryer in Bhutan

The technical and financial performance of an existing solar crop dryer at Khao-kor, Thailand has been evaluated for possible replication in Bhutan. The complete dryer system has been modelled using TRNSYS and the collector area was optimised to give minimum drying cost. From the evaluation, the average collector, pick-up and system efficiencies were determined as 44 %, 24 % and 16 % respectively. The solar contribution to the load is 33 % when the dryer is used for 303 days in a year. Chilli and beef were selected as products to be dried as they are an integral part of Bhutanese cooking. The solar dryer system was found cheaper to dry beef while an electric heating system was found cheaper to dry chilli.