Solar irradiance is 1361 W/m^2 before accounting for losses due to the atmosphere, the sun not being directly overhead, solar panels not converting all waveleng

Solar irradiance is 1361 W/m^2 before accounting for losses due to the atmosphere, the sun not being directly overhead, solar panels not converting all wavelengths to electricity, etc. But none of those inefficiencies matter, because 1.3kW in a square meter means that we have an upper bound of solar power generation for a footprint roughly equal to that of a server rack, and the power is roughly that of one server (for compute; storage servers can have lower power density). Since servers are in fact operated in racks, we immediately know that solar power on the roof of a datacenter will fall short by at about two orders of magnitude at a minimum.