CO2 Sequestration through Deep Saline Injection and ...

The MTSA field differs from a conventional solar tower system which has only one tower with
as the central receiver but rather a group of solar towers with closely packed neighboring
heliostats. The advantage is that the MTSA can use solar radiation which would normally fall on
the ground between widely spaced heliostats further away from the tower of a conventional type
solar tower system. Therefore, greater ground coverage can be achieved [52]. The position of the
MTSA forms a repetitive two dimensional regular pattern called bravais lattice. This lattice can
then be repeated in space to cover the ground. Figure 23 bellow illustrates a field of a MTSA and
the bravais lattice.
Figure 23
MTSA and Bravais Lattice [52]
3.7.2. Heliostat Design
In heliostat design it is important to ensure that the reflectors will not interfere with eachother as
they move through space on their axis. The concept of unimpeded space volume is important
when considering the chosen shape for the heliostat. The unimpeded space volume represents
the real space that could be occupied by the heliostat as it moves through space. As long as
nothing enters this volume, the motion of the heliostat will not be impeded and no collision is
possible. Figure 24 shows a conventional rectangular heliostat with two axis rotation. The
unimpeded space is determined by rotating the heliostat about one axis and then the other and
taking the confluence of the path volume as shown in Figure 25. The rectangular heliostat is first
rotated about the vertical axis in Figure 25 (a) to form a cylindrical volume. The cylindrical
volume is then rotated about the second axis to form a barrel shape in (b). The volume seen in
Figure 25 (b) is the unimpeded space volume for the conventional rectangular heliostat. This
volume defines the packing structure for the heliostat field shown in
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