This work presents a case study where four well-known derivative-free solvers are benchmarked on several instances based on the \(\textsf{solar}\) suite of problems: an easy to use, freely available and open-source Concentrated Solar Power (CSP) plant simulator. The \(\textsf{solar}\) simulator provides a collection of ten test problems designed to reflect real-world blackbox optimization challenges. The design of CSP plants involves solving complex and often computationally expensive optimization problems. These problems rely on highly diverse models which may be difficult to interface with optimization solvers. As a result, standardized benchmark problems for optimization solvers in the CSP design field are scarce. Such benchmarks are essential for selecting the most appropriate solver for a given optimization problem. The \(\textsf{solar}\) problems model numerous components of the power plant, ranging from the design of the heliostat field to the choice of turbine.