The discretized curve is established up to the center point of the field, at which point it is reflected about the point
to complete the discretized field. The field is therefore positioned and sized based on the peak scenario as that is the
time of day in which maximum radiation can be harnessed. The angle of the mirrors is such that the normal bisects
the angle through which light is reflected. For peak times of day this is simply represented as
2
I D
The mirror field needs to move to track the sun throughout the day. The simplest model fixes an axis of rotation
at the center of the mirror in x and y. The new mirror angle is then calculated simply by combining the angle
associated with the mirror position and the angle of the incoming radiation 2
2
D T
P
However, at higher angles blocking and shading become significant. Therefore a model of etendue matching
curves for off peak times is used for the lower angles.
This model also runs an unconstrained optimization, taking into account the incoming radiation angle such that the
objective function becomes 1 2 f x ª º cos cos cos ID I D DT