Civil Engineering Reference
In-Depth Information
FIGURE 9-1
Solar thermal power plant schematic for generating electricity.
A major benefit of this scheme is that it incorporates the thermal energy
storage for duration in hours with no degradation in performance, or longer
with some degradation. This feature makes the technology capable of pro-
ducing high-value electricity for meeting peak demands. Moreover, com-
pared to the solar photovoltaic, the solar thermal system is economical, as
it eliminates the costly semiconductor cells.
9.1
Energy Collection
The solar thermal energy is collected by concentrators. Three alternative
configurations of the concentrators are shown in
Figure 9-2
.
Their main
features and applications are as follows:
9.1.1
Parabolic Trough
The parabolic trough system is by far the most commercially matured of the
three technologies. It focuses the sunlight on a glass-encapsulated tube run-
ning along the focal line of the collector. The tube carries heat absorbing
liquid, usually oil, which in turn, heats water to generate steam. More than
350 MW of parabolic trough capacity is operating in the California Mojave
