Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-421-2

International Heat Transfer Conference 15
August, 10-15, 2014, Kyoto, Japan

Design and Analysis of a Low-Profile, Concentrating Solar Thermal Collector

Get access (open in a dialog) DOI: 10.1615/IHTC15.sol.008611
pages 7519-7533

Abstrakt

Solar energy is the most abundant renewable energy resource for most locations on the planet. About one half of global energy demand is associated with fulfilling thermal requirements for buildings and industrial processes. Thus, there is a vast industrial and commercial market for the supply of 100 – 400oC thermal energy (currently met by and electricity). Concentrating solar thermal collectors can potentially meet this demand, but conventional designs (troughs and dishes) are hard to integrate into industrial and commercial roofs. In this paper, a low profile (<10 cm height) design based on a linearly actuated catadioptric optical system (using both reflective and refractive optical elements) is reported which achieves ~ 4 times concentration throughout the day. In addition, vacuum packaging is used to minimize heat loss, maintaining a high temperature supply of thermal energy (100 – 385oC). Ray tracing simulations show that the optical efficiency ranges from 52% to 72% as the incident light angle varies from 0o to 45o — indicating this collector is effective between 9 am and 3 pm. Combining ray tracing simulation with a CFD model, we predict that the collector efficiency will range from 23% - 44% with a fluid average temperature of 220oC during 9 am to 3 pm on a sunny day (e.g. under 1000 W/m2 global horizontal irradiance). Overall, the proposed collector design brings together several novel components which make it suitable for utilization in industrial and commercial heating applications.