Desenvolvimento e análise experimental de coletor solar tipo tubo evacuado modificado dotado de concentrador cilíndrico-parabólico.

Abstract

The sun is the largest source of energy on Earth, with approximately 885 million terawatt hours (TWh) reaching the surface of the planet each year. According to the Ministry of Science, Technology and Innovation, the installation of CSP (Concentrating Solar Power) plants in an area of only 0.5% of the total size of northeastern Brazil could result in a generation capacity of 600TWh / year, which would be sufficient to meet the current national energy demand. Although many researches have recently contributed to the development of different types and configurations of collectors and concentrators, the technology for the thermal or electrical application of concentrated solar power energy is still not well known or used, mainly in Brazil. The present work describes the research, design, development, operation and experimental analysis of an all-glass evacuated tube collector type equipped with parabolic trough concentrator and a solar tracking device. It concentrates the solar rays in a focal beam where is installed the solar collector with a modification that stands out for making the physical separation of the cold and hot flows of the working fluid. The construction of the structure proved to be very faithful to the design. The experiments were performed on open sky days and repeated to different flows with no hot fluid recirculation in the system. The maximum difference between the inlet and outlet temperatures of the working fluid was 28°C for a volumetric flow rate of 100ml / min, the lowest tested one. The maximum thermal efficiency reached almost 39%. Several factors that influenced the overall performance of the system were observed and will be used in future works.