I am currently working on a project that works with solar panels on Mars and I am trying to calculate how much power I would get from a solar panel on the surface. I have values such as solar irradiance, the area of the solar panel, and the efficiency of the panel. I found one formula: Power=area x efficiency x solar irradiance x performance ratio

However, I cannot find a standard value for performance ratio anywhere and I don't have a reliable source on this equation either, so I can't use it on a paper.

So, does anyone know formula out there that allows me to calculate the power delivered from a solar panel? If so, I would greatly appreciate it and if there is a reliable source (like scholarly paper), please leave a name for that as well.

  • \$\begingroup\$ Where did you find that formula - please provide a link to that document. \$\endgroup\$
    – Andy aka
    Apr 9, 2020 at 17:03
  • \$\begingroup\$ Same comment I made: Check out books like Duffie & Beckman Solar Thermal Engineering for the question you posted here: academia.stackexchange.com/q/147459/72855 \$\endgroup\$
    – Solar Mike
    Apr 9, 2020 at 17:12

1 Answer 1


Have a look at Sustainable Energy, without the hot air, Prof. David Mackay, ISBN 9780954452933. It's also on the web. http://www.withouthotair.com

He says:

Typical solar panels have an efficiency of about 10%; expensive ones perform at 20%. (Fundamental physical laws limit the efficiency of photovoltaic systems to at best 60% with perfect concentrating mirrors or lenses, and 45% without concentration. A mass-produced device with efficiency greater than 30% would be quite remarkable.) The average power delivered by south-facing 20%-efficient photovoltaic panels in Britain would be

  20% × 110 W/m2 = 22 W/m2.


The 110 W/m2 is derived on the previous page, for a average south-facing roof in Britain: raw energy = 1,000 W/m2, with a correction of 32% for orientation and 34% for cloud = 108.8 W/m2. Tracking systems, non-Earth locations, no cloud would affect all of these.

There are many references in this book for you to follow up. Wikipedia page Solar Cell Efficiency also has several dozen references.


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