Solar PV

Insolation on Earth's Surface

Irradiance, or Insolation, on Earth's surface

Average annual solar radiation arriving at the top of the Earth's atmosphere is roughly 1361 W/m2. The Sun's rays are attenuated as they pass through the atmosphere, leaving maximum normal surface irradiance at approximately 1000 W /m2 at sea level on a clear day. When 1361 W/m2 is arriving above the atmosphere (when the sun is at the zenith in a cloudless sky), direct sun is about 1050 W/m2, and global radiation on a horizontal surface at ground level is about 1120 W/m2

The latter figure includes radiation scattered or re-emitted by atmosphere and surroundings. The actual figure varies with the Sun's angle and atmospheric circumstances.

Ignoring clouds, the daily average insolation for the Earth is approximately 6 kWh/m2 = 21.6 MJ/m2.

This figure shows the solar radiation spectrum for direct light at both the top of the Earth's atmosphere (represented by yellow area) and at sea level (red area). The sun produces light with a distribution similar to what would be expected from a 5778 K (5505 °C) blackbody, which is approximately the sun's surface temperature. As light passes through the atmosphere, some is absorbed by gases with specific absorption bands. Additional light is redistributed by Raleigh scattering, which is responsible for the atmosphere's blue color. These curves are based on the American Society for Testing and Materials (ASTM) Terrestrial Reference Spectra, which are standards adopted by the photovoltaics industry to ensure consistent test conditions and are similar to the light that could be expected in North America. Regions for ultraviolet, visible and infrared light are indicated.  (Ref:- Credit Wikipedia)

Now we will see the area of land that is required for Power Generation using Solar Photo Voltaics.
The figures in the Table are Public on the Web from The Power Supplier...
----- Interestingly The Suppliers always Talk about The Number of Residences that can be supplied!... 
===== Funny that!... I thought that the Idea was for Individual Houses to Put Their Own Solar Panels on their Own Roofs and leave the Big Solar Farms to Supply The Replacement Power For The Coal and Nuclear Plants that "The Green Industrial Complex" has Convinced Governments can be Shut Down, as The Power generation to replace them can be supplied using Solar, Wind and Bio-Fuel Power Generation... See Michael Moore This is The "Approved!" version 

There is a Horizontal Scroll Bar, but to see it one has to scroll to the bottom of the Sheet, and then, just above the "Sheet 1, Sheet Two, Sheet 3 Tabs" if you don't see it click and it will appear... One can then scroll back up the page and it will remain available... unless you scroll too far up and the Above Paragraph starts to scroll... One has to be a bit careful... Otherwise one has to scroll down and repeat the operation to get the Horizontal Scroll Bar!

Generation - MW·h - of Topaz Solar