Abstract:
Direct-absorption solar thermal collectors have recently
been shown to be a promising technology for photothermal
energy conversion but many parameters affecting the overall
performance of such systems haven’t been studied in depth, yet
alone optimized. Earlier work has shown that the overall
magnitude of the extinction coefficient can play a drastic role,
with too high of an extinction coefficient actually reducing the
efficiency. This study investigates how the extinction
coefficient impacts the collector efficiency and how it can be
tuned as a function of depth to optimize the efficiency, and why
this presents a unique design over conventional solar thermal
collection systems. Three extinction profiles are investigated:
uniform, linearly increasing, and exponentially increasing
