_____________________________________________________________________________________________________ *Corresponding author: E-mail: lyjoe2000@gmail.com; Current Journal of Applied Science and Technology 38(6): 1-7, 2019; Article no.CJAST.54884 ISSN: 2457-1024 (Past name: British Journal of Applied Science & Technology, Past ISSN: 2231-0843, NLM ID: 101664541) Drying Performance of Beans Using Natural Convective Step Type Solar Dryer S. Joshua Davidson 1* , J. John Gunasekar 1 and K. Prasanthkumar 2 1 Department of Renewable Energy Engineering, Agricultural Engineering College and Research Institute, Kumulur, Trichy, Tamil Nadu, India. 2 Department of Farm Machinery and Power Engineering, Agricultural Engineering College and Research Institute, Kumulur, Trichy, Tamil Nadu, India. Authors’ contributions This work was carried out in collaboration among all authors. Author SJD designed the study, performed the statistical analysis, wrote the protocol and wrote the first draft of the manuscript. Author JJG managed the analyses of the study. Author KP managed the literature searches. All authors read and approved the final manuscript. Article Information DOI: 10.9734/CJAST/2019/v38i630490 Editor(s): (1) Dr. Hamid El Bilali, Research Fellow, Centre for Development Research, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria. Reviewers: (1) N. Manikanda Prabu, Presidency University, India. (2) Jackson Akpojaro, University of Africa, Toru-Orua, Nigeria. (3) Dajsingchai Wongkhomton, Mahasarakham University and Ramkhamhaeng University, Thailand. Complete Peer review History: http://www.sdiarticle4.com/review-history/54884 Received 01 December 2019 Accepted 03 February 2020 Published 05 February 2020 ABSTRACT Development of appropriate technologies for conversion of solar radiation to thermal energy is essential for fruit and vegetable preservation. A natural convective step type solar dryer with 10 trays was used. The drying parameters such as drying temperature, drying rate and dryer efficiency were studied on bright sunny days from top to bottom of the dryer using unblanched and blanched beans. The maximum and minimum temperatures observed were 84ºC and 50ºC at no load, 59ºC and 75ºC using unblanched beans and 51 and 75ºC using blanched beans. While drying on a sunny day, the moisture content removed was from 72 to 14% for unblanched beans and 76 to 7.32% for blanched beans. On quality evaluation, the high rehydration coefficient was found in blanched beans (0.76) than in unblanched beans (0.52). The collection efficiency was found to be 40.92% and drying efficiency was found to be 15.85% using unblanched beans and 18.75% using blanched beans. Original Research Article