Techno-economic Analysis of a Hybrid Solar Dryer with a Vacuum Tube Collector for Hibiscus Cannabinus L Fibre

Abstract

Solar energy is one of several types of renewable energy and has numerous applications. Types of solar energy include photovoltaic, thermal, and thermophotovoltaic modes. Drying is an application of thermal solar energy which is used to remove water from a sample. This study aims to evaluate certain open drying methods as compared with modern thermal drying methods. The dried samples were a type of natural fibre commonly known as kenaf (Hibiscus Cannabinus L). The test amounts were 175kg and 1400kg, respectively. Thermal drying uses several components, including an evacuated tube collector, water storage tank, heater, air intake, a pump and a drying chamber. The parameters to be measured included weight, water content, time, and electricity usage. Dryer performance was evaluated in terms of water extraction rate, exact water extraction rate, specific energy usage, dryer operational costs, and specific operational costs. The results of the evaluations indicate that drying with the maximum load of 1400 kg increased the extracted water, specific water extraction rate, and dryer operational costs by 97.27 kg/hour, 39.86 kg/kWh, and 3.72 Malaysian ringgit (approximately 0.90 USD). Specific energy consumption and specific operating costs fell by 0.10 kWh/kg and 0.05 Malaysian ringgit/kg (0.012 USD/kg). Based on these findings, economic analysis was carried out to estimate the profitability and best frequency of drying. The results indicate that a maximum load of 1400 kg is superior to the open drying method, with an annual yield and ROI period of RM 64992 (15,723 USD) and 3.7 years, respectively