The peak sunshine in different areas is different, so is the power generation.

For example, the annual average daily peak sunshine in Shenzhen, Guangdong Province is 3.9 1.

Then every day is1* 3.91= 3.91degree.

Look where you are.

The sunshine peak in Yunfu City is 3.78 hours.

The average daily power generation in that year was 3.78 degrees.

The power generation of 20kW in 365 days is 20*3.78*365=27594 degrees.

You can consult me if you don't know (Shenzhen Huayang Solar Energy)