Analysis of Designs and Performance of Existing Greenhouse Solar Dryers in Kenya
Keywords:
Analysis, design,, greenhouse dryers, Kenya, performanceAbstract
Solar drying offers a convenient, cheaper and environmentally friendly way to dry food. In Kenya, solar dryers have been developed and introduced by different actors. However, their technical and economic performance is unknown. This study assessed the technical performance of existing greenhouse dryers in Kenya, by focusing on their design, use and performance. The data was further analysed to identify the correlation between identified parameters. The study was conducted in parts of Eastern and Central regions in Kenya. A total of 18 dryers were sampled from 50 identified dryers. The average size of greenhouse dryers was 8.12 m long, 3.95 m wide and 2.37 m high. The study also analysed designers, selection of construction, internal configuration, and cost of dryers. Generally, a good consideration was noted in these aspects. 24% of dryers experienced losses over 10%. Major causes of losses were cold weather, spillage and poor ventilation. Most dryers achieved good quality products, with 29% getting less than 50% of grade 1. On average, the drying rate was 13, 56, 48 and 64 hours for mangoes, bananas, cassava and butternut, respectively. These drying rates relate well with other studies. Overall, correlation analysis showed consistence in dryer design, use and performance.
References
Aliyu, A. B. and Jibril, H. 2009. Utilization of greenhouse effect for solar drying of cassava chips. International Journal of Physical Sciences, 4(11): 615-622.
Akinjiola, P. O. and Uthamalingam, B. 2012. Mass-heater supplemented greenhouse dryer for post-harvest preservation in developing countries. Journal of Sustainable Development, 5(10): 2012.
Barnwal, P. and Tiwari, A. 2008. Design, construction and testing of photovoltaic integrated greenhouse dryer. International Journal of Agricultural Research, 3(2): 110-120.
Barnwal, P. and Tiwari, G. N. 2008. Life cycle cost analysis of a hybrid photovoltaic/thermal greenhouse dryer. Open Environmental Sciences, 2: 39-46.
FAO Bulletin No. 109. 1994. Grain storage techniques: Evolution and trends in developing countries. Rome, Italy. GoK. 2007. Ministry of Planning. Economic Survey 2007.
HCDA. 2010. Kenya Horticultural Export Statistics for January to March, 2010. Marketing Newsletter, June, 2010. Vol. 5 Issue No. 6.
Janjai, S., Lamlert, N., Intawee, P., Mahayothee, B., Bala, B. K., Nagle, M., Muller, J. 2009. Experimental and simulated performance of a PV-ventilated solar greenhouse dryer for drying of peeled longan and banana. Solar Energy, 83: 1550-1565.
Janjai, S., Intawee, P., Kaewkiewa, J., Sritus, C., Khamvongsa, V. 2011. A large-scale solar greenhouse dryer using polycarbonate cover: Modelling and testing in a tropical environment of Lao People’s Democratic Republic. Renewable Energy, 36: 1053-1062.
Janjai, S. 2012. Greenhouse type solar dryer for small-scale dried food industries: Development and dissemination. International Energy and Environment Foundation, 3(3): 383-398.
KHCP (Kenya Horticulture Competitiveness Project) – USAID. 2013. Horticulture Market News: September 2013. Kuchi, V. S., Gupta R. and Kachwaya, D.S. 2014. A review on dehydration of chilli. Plant Archives 14 (2): 637-642.
Mercer, D. G. 2012. A comparison of the kinetics of mango drying in open-air, solar, and forced-air dryers. African Journal for Food, Agriculture, Nutrition and Development, 12(7): 6835-6852.
MoA. 2010. Economic Review of Agriculture, 2010. Ministry of Agriculture, Nairobi, Kenya.
Ogheneruona, D. E. and Yusuf, M. O. L. 2011. Design and fabrication of a direct natural convection solar dryer for Tapioca. Leonardo Electronic Journal of Practices and Technologies, 18; 95-104.
Sahu, K. T, Gupta, V, Singh, A. K. 2016. A review on solar drying techniques and solar greenhouse dryer. IOSR Journal of
J. Postharvest Technol., 2018, 06(1): 27-35 34
Ndirangu et al. (Analysis of Designs and Performance of Existing Greenhouse Solar Dryers in Kenya)
Mechanical and Civil Engineering (IOSR-JMCE), 13(3): 31-37.
Singh,V., Hedayetullah, Md. Zaman,P., Meher, J. 2014. Postharvest Technology of Fruits and Vegetables: An Overview. Journal of Postharvest Technology, 2(2): 124-135.
Whitfield, D. E. 2000. Solar drying. International Conference on Solar Cooking. Kimberly, South Africa, 26th–29th November 2000.