Weird, a parabolic dish makes no sense if you point it directly at the sun. Most panels will be pointed at suboptimal angles. A flat plate mounted on the existing az/el tracking of the original dish would be optimal. Stuff that plate full of panels and track the whole contraption to the sun and all panels will be perfectly aligned.
If you replace the panels with mirrors and have an ultra efficient high power panel in the middle the dish form factor would work (and this is how they built them in the 80s though I think they were heating water for steam back then) but that's not what they're doing here.
If you replace the panels with mirrors and have an ultra efficient high power panel in the middle the dish form factor would work (and this is how they built them in the 80s though I think they were heating water for steam back then) but that's not what they're doing here.