Explain with a very simple calculation the quantity 76kWhm2d

Explain, with a very simple calculation, the quantity 7.6kWh/m^2/day quoted as below. On a clear day, typical irradiation at 1.5 AM: 1000 W/m^2 (where\'d the rest go?) 10% of above is indirect, diffuse radiation (scattered light from the rest of the blue sky!) 7.6 kWh/m^2/day (no tracking; constant AM)

Solution

This is the average annual irradiance value which has been obtained using data analytics. So the problem has assumed the day irradiance value as 7.6KWh/m²/day