A Study for the Use of Solar Energy for Agricultural Industry - Solar Drying System Using Evacuated Tubular Solar Collector and Auxiliary Heater -

Abstract

Purpose:The objectives of this study were to construct the solar drying system with evacuated tubular solar collector and to investigate its performance in comparison with indoor and outdoor dryings. Methods: Solar drying system was constructed with using CPC (compound parabolic concentrator) evacuated tubular solar collector. Solar drying system is mainly composed of evacuated tubular solar collector with CPC reflector, storage tank, water-to-air heat exchanger, auxiliary heater, and drying chamber. Performance test of solar drying system was conducted with drying of agricultural products such as sliced radish, potato, carrot, and oyster mushroom. Drying characteristics of agricultural products in solar drying system were compared with those of indoor and outdoor ones. Results: Solar drying system showed considerable effect on reducing the half drying time for all drying samples. However, outdoor drying was more effective than indoor drying on shortening the half drying time for all of drying samples. Solar drying system and outdoor drying for oyster mushroom showed the same half drying time. Conclusions: Oyster mushroom could be dried easily under outdoor drying until MR (Moisture Ratio) was reached to about 0.2. However, solar drying system showed great effect on drying for most samples compared with indoor and outdoor dryings, when MR was less than 0.5.

Solar process heat in industrial systems – A global review

“…Sebaii et al reviewed the fundamentals and research work done in solar drying systems [18]. Lee studied and constructed solar drying system with an evacuated tube solar collector and also evaluated the system performance with indoor and outdoor drying [45]. Pirasteh et al reviewed the development of solar drying applications in industry and agriculture, energy consumption capacity and aspects of using solar dryer from multiple viewpoints [70].…”

Drying of Carrot Strips in Indirect Solar Dehydrator with Photovoltaic Cell and Thermal Energy Storage

“…The agriculture of the Antofagasta Region in Chile, in addition to its potential contribution to regional food autonomy, constitutes the basis of the existence and reproduction of Atacama culture (Lickan Antay) since it is a form of agriculture but in the desert heights, associated with water scarcity and abundance of the sun [7]. The solar resource of the Atacama Desert of this region reaches an average global horizontal irradiance (GHI) of 7.2 kWh/m 2 per day [8], positioning this area as a potential pole of development of technologies that take advantage of solar energy (SE), defined as one of the non-conventional renewable energies (NCRE) due to its inexhaustible, non-polluting character and because it does not present associated environmental hazards [9,10].…”

“…It is considered a high-cost procedure, which restricts the supply of dehydration services for small producers. It is because of this that the economy of the drying process is affected and dependent on a stable supply of fuel, which, in developed countries, must satisfy between 7-15% of the industrial energy for drying [9]. The inefficiency of the drying processes due to the high energy expenditure, estimated at 75% of the total cost of the process [12], has led to the use of alternative sources of energy, such as the SE, as well as the development of models to achieve the best process conditions.…”

Utilization of Solar Energy in Agricultural Machinery Engineering: A Review

“…For application of solar energy in agriculture, a solar drying system based on an evacuated tube collector (ETC) and auxiliary heater was constructed at the Kangwon National University, South Korea, for drying of agricultural products like potatoes, radishes, carrots, and oyster mushrooms, as illustrated in Figure 2 (Lee, 2013). Purohit et al (2006) performed a comparative financial analysis of solar drying versus open-air drying on the basis of certain calculated results and discussions.…”