2.3.2. Fresnel collector
The Fresnel collector (Figure 2a) is a linear concentrating solar thermal collector for industrial process heat
applications, used as a solar boiler. The collector is made up of 4.06 m long modules, defined by the length of the
SCHOTT PTR70 vacuum absorber tube. Three modules are depicted in Figure 3 below. The total collector width is
7.5 m, while the aperture width – the cumulative width of the 11 primary mirror rows – is 5.5 m. The total height ofthe collector is around 4.5 m, depending on the type of ground and the foundations. The 11 mirror rows are tracking
the sun in one axis, while the receiver, consisting of an absorber tube, secondary mirror and housing, remains fixed.
The efficiency of these collector systems depends on various factors, including geographic location, operating
conditions (e.g. operating temperature and corresponding heat losses), field layout, and orientation of the collector
field.
Figure