In this paper, comparative analyses between two newly proposed circular heliostat field layout designs, i.e. Campo radial-staggered and biomimetic spiral layouts are carried out. Moreover, different optimization objectives including annual weighted efficiency, annual unweighted efficiency, and levelized cost of energy are considered for field layout optimization. In addition, the effects of different design variables, such as the central tower height, number of heliostats in the field, receiver's dimensions and size of the mirrors on the field thermal and economical capabilities are investigated. Finally, the analysis' results indicate that optimum weighted efficiency for Campo radial-staggered and biomimetic spiral layouts are 61.6% and 61.5%, whereas the optimum levelized cost of energy for both methods are 32.4 USS/MWh. (C) 2016 Elsevier Ltd. All rights reserved.