Volume 18, No. 6, 2021
A Comparative Study On The Efficiency Of Concentrating Solar Thermal Technologies In Use At Different Geographical Locations
Pankaj Kumar , Krishna Kumar Sinha , M. K. Gupta , M. K. Banerjee
Abstract
A comparative study on the efficiency of concentrating solar thermal (CST) technologies is carried out. Modelling of experimental data at five different locations of India is employed to calculate the absorbed thermal energy by each of four different types of preselected collectors; the collectors for each of the selected locations, thermal losses are calculated. The total thermal energy accessible from the collectors, i.e., the thermal yield of each collector, has been computed using the results obtained thus far. The thermal efficiency of a collector is defined as the ratio of the actual thermal yield to the potential amount of collectable thermal energy (solar radiation x aperture area). The efficiency of collectors that use tracking systems to follow the sun throughout the day is calculated using direct normal solar irradiation. In contrast, the efficiency of compound parabolic collector is calculated using both global and diffuse irradiance. The performance simulations used to produce the data for the comparisons give, as the output, yield and thermal loss data on an hourly basis over a complete year. This data used to calculate the average annual yield or average annual thermal efficiency shows that newly designed parabolic dish collector is superior to others in respect of thermal efficiency. In order to ensure the best possible comparison between collector types, only the performance of individual collector has been considered without regard to other factors, such as solar field losses or boiler efficiency, that are specific to an actual installation.
Pages: 1199-1207
Keywords: Solar collectors, solar irradiance, efficiency, latitude, modelling