Renewable energy is expanding as a sustainable and pollution-free resource, and improving its efficiency is crucial. Solar energy, which has been of interest since the 19th century, is one such source. One utilization method involves concentrating technologies, such as linear parabolic collectors, which are used alongside fossil fuel power plants in our country. In these systems, sunlight is reflected by mirrors onto a thermal absorber, transferring its energy. This paper examines the geometric structure of elliptical shapes as a dark body and designs three experimental samples: 1) A control structure with a circular absorber, 2) An initial dome-shaped absorber, and 3) An elliptical absorber, which demonstrated superior performance by achieving maximum energy absorption. The receiving area is 0.6×0.28 m² ± 0.005 m², and the samples can heat 250 mL of water. The observed maximum temperatures were 46.9°C, 54.1°C, and 63.5°C, respectively, with the elliptical design achieving 16.6°C higher than the control. The designs were created using CorelDRAW and SolidWorks, and the data were simulated in COMSOL, showing good agreement with experimental results. The simulation revealed that the control structure only reflects light once, whereas the elliptical structure reduces the aperture area and concentrates rays, increasing multiple reflections onto the absorber and enhancing energy absorption. Overall, the thermal efficiency of the elliptical structure is approximately 35% higher than the control, indicating better performance and greater practicality in concentrating solar systems.