10 years ago i was in hot location in the south of Tehran(Eslamshahr). I designed some physics show for students by some dishes was covered via some mirrors. every usual dish have 4800 *1cm2 parts of mirrors. the tempثrature in focal length about 90-100 cm front of mirror is very huge, h suggest it was about 500-600 centigrade degree . you can supply a dish and cover it by 1cm2 parts of glass mirrors.