The Process of Designing Surrounding Heliostat Fields for a Central Receiver Solar Power Plant

In this study, a preliminary design of a surrounding heliostat field for a Central Receiver Solar Power Plant (CRSPP) is presented under the specified meteorological conditions in Kerman, Iran due to the high solar radiation intensity in this area. Radial staggered configuration is used for the heliostat field as one of the best configurations of the heliostat field layout. The design is based on two basic parameters i.e. a simplified blocking factor and an additional security distance. An algorithm is developed based on the vector geometry to select an individual heliostat and calculate its characteristic angles at different times of the day and the year at different locations. After determining the location of heliostats in the field, the local heliostat field efficiency for each heliostat is calculated in order to find the most efficient heliostats in the field. The heliostats with higher efficiencies are chosen to be located in the field. The results show that the higher efficiency belongs to the heliostats on the north axis, near the tower. The density of mirrors is higher at the south of the tower, and is decreased slowly toward the west/or east, and finally approaches to the lowest level at the north of the tower. In other words, locations with lower density have higher efficiency and vice versa. Finding the optimum locations of the heliostats is a complex process and requires great effort because of the large numbers of heliostats involved in a CRSPP.