Performance simulation of the central-receiver solar concentration system based on typical meteorological year data

Abstract

When solar radiation is utilized as a high-temperature heat source, performance simulation of solar concentration systems is important, especially for a central-receiver system that involves a large number of sun-tracking reflectors. To account for the intermittent nature of solar radiation, an annual performance based on 8760 hourly simulations is desirable. Therefore, this study focuses on a more realistic simulation of a central-receiver concentrator system with the Typical meteorological year (TMY) data that typify characteristic meteorological conditions at a specific location. Optical efficiency simulations of the Daegu central-receiver concentrator system were performed with a Monte Carlo ray-tracing method, and the Direct normal irradiance (DNI) in the TMY data set generated from the database of Korea Meteorological Administration (KMA) was evaluated. The TMY data in Daegu show that 80 % of the DNI values are smaller than 500 W/m² and the annual insolation of 931 kWh/m²/year corresponds to approximately one third of that calculated from the clear-sky DNI model. Monthly optical efficiencies range from 67.8 % in October to 63.2 % in June in the base case. In contrast to the difference in solar insolation, the optical efficiencies based on the clear-sky model are slightly smaller than the efficiencies based on the TMY data, with deviations within approximately 1 %. The small difference implies that the clear-sky model can be substituted when simulation or optimization of the optical efficiency is of interest.