The E100C is the replacement for Envirofan fan mechanism for the brick size and quad fan systems.
Speed test 29-6-21 (Weather 15 degrees partly cloudy with sunny breaks) on solar 1st quad systems @ 18m from single solar panel & 2nd quad fan system linked (daisy chained) 10m from 1st quad fan system..
Cloud cover @ 40% shade= Average of 2.5m/sec (9km/hr) for 1 fan motor. Times (x) by 4 to calculate on a quad fan system.
Sunny = Average of 4.5m / sec (16.2km/hr for 1 fan motor. Times (x) by 4 to calculate on a quad fan system.