What is the Sun's energy content at the Earth's equator?

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  • #1
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Summary:

What is the energy content of the sun rays falling on the equator in summer months

Main Question or Discussion Point

Hello,

I am looking to find out the energy (or power) content of the sunlight incident on the equatorial region during summer months. I assume, this is highest in that region. I actually want the direct energy content - not, say, the electrical output from a solar panel. This could be, in some way, a measure of heat. This may be available as KWh/square meter which will be most preferable.

Many thanks in advance for your help.
 

Answers and Replies

  • #3
phyzguy
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I am looking to find out the energy (or power) content of the sunlight incident on the equatorial region during summer months. I assume, this is highest in that region. I actually want the direct energy content - not, say, the electrical output from a solar panel. This could be, in some way, a measure of heat. This may be available as KWh/square meter which will be most preferable.
Note that the solar insolation at the equator actually peaks at the equinoxes (when the sun is directly overhead) and is lower in summer and winter. Also, note that the insolation is a power density in kW/square meter, and would need to be integrated over some time period to give an energy density. At the Earth's surface it is about 1kW/m^2, as described in the article @Borek posted.
 
  • #4
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Borek, phyzguy : Many thanks! This will serve my purpose very well.
 
  • #5
OmCheeto
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At first I thought this was some kind of scientific version of "mansplaining"

The actual direct solar irradiance at the top of the atmosphere fluctuates by about 6.9% during a year (from 1.412 kW/m² in early January to 1.321 kW/m² in early July) due to the Earth's varying distance from the Sun...

How on Earth can a constant vary?
But then I saw:

The solar constant is an average of a varying value.

Ok then.
 
  • #6
Borek
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Yes, the name is a bit of a misnomer.
 
  • #7
OmCheeto
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Yes, the name is a bit of a misnomer.
Were I a bit more ambitious, I'd go back through all 12 years of my PF posts, and put in a "± 6.9%" for all my solar experiments.
But, I'm not in the slightest bit ambitious, so, never mind.
 
  • #8
sophiecentaur
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How on Earth can a constant vary?
You are right to question some sloppy terminology.
Bear in mind that the Earth's orbit round the Sun is not an exact circle. That means, despite any tilt or atmospheric factors, it can't be a 'constant'. It's a bad idea to get too hung up on 'words' when experimental evidence challenges them.
 

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