Solar Water Heating System in a Textile Industry — a Case Study

Abstract

Textile industry is one of the largest energy consuming industries in India with an annual consumption of 4.5 million tonnes of coal. Of the total energy consumed in a textile mill, about 90% is in the form of thermal energy (steam) and the rest is in the form of electricity. The fuel used for steam generation is mostly coal except in Bombay where fuel oil is used. The operating temperatures of various processes in the industry range from 50°C to 220°C. Of the total thermal energy input 80 to 85 per cent is used for processing and drying. (Table 1 gives the estimates of specific hot water consumption in a textile industry for various processes and the desired temperatures.) Solar energy, which is pollution free and inexhaustible, can easily provide the hot water at the desired temperatures and the technology is already available for such solar collectors. In a textile mill solar energy can be used in various forms e.g. as hot water, hot air and low pressure steam. Also the textile mills have large roof area, generally south slopping, which can be used to install the solar collectors for harnesing the solar energy.