This article presents an innovative approach for optimizing the dimensions of cylindrical receivers for solar tower systems. In this approach, a single set of rays, representative of a complete annual ray-tracing simulation of the solar tower system, is used and processed to evaluate numerous receiver designs simultaneously and to select the optimum. The simultaneous evaluation of receiver designs is achieved by exploiting the geometrical properties of the intersection between a ray and a cylinder, which allows estimating the annual energy intersected by receiver of different heights without the need for processing the annual set of rays more than one time. Once the annual intersected energy is known for each receiver, the application of a costing function estimating the receiver cost as a function of its surface area allows to estimate their cost and, therefore, to select the receiver dimensions that will yield a minimum surface area for a given annual energy interception factor. The overall workflow to carry out the mentioned receiver optimization approach has been implemented by adapting several open source tools The Cyprus Institute (CyI) is developing in collaboration with the Australian National University (ANU) to assist in the modelling, analysis, design and optimization of Concentrated Solar Thermal (CST) systems. This article also presents a detailed overview of the overall simulation workflow as well as a case study demonstrating the capabilities of the approach.