The break even point might be near, currently every mirror is controlled by an open loop controller of some sophistocation to point exactly right relative to th

The break even point might be near, currently every mirror is controlled by an open loop controller of some sophistocation to point exactly right relative to the sun, time of day and tower. But the CSIRO has a system where a camera looks at the mirrors from the tower and estimates quite well the mirror angle from the shade of blue reflected. This makes it closed loop control, one sensor for many mirrors and simple actuation like lead screw with raise/lower controls possible.