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Negative and positive values of Solar radiation during night
 
  
 
  
 
 
 
 
 
 
    
        
        asked 9 years ago  
 
 Durr's avatar  
 
 
 
 
    
        
        updated 5 years ago  
 
 __AmirRoth__'s avatar  
 
 
 
 
 
I have some actual weather data that contains global solar radiation values. I have noticed that it has positive and negative values at night time, please see below. Should it be zero during night time or I am missing something? 
 
P.S: The unit is wrong for global solar radiation. 
 
Weather_filw
 
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        answered 9 years ago  
 
 Archmage's avatar  
 
 
 
 
 
It probably should be zero but it is normal to have some small (depending on what the units really are) noise in the sensor reading.  If this data were used in EnergyPlus it would be ignored when the sun's calculated position is not actually above the horizon.  
 
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        Asked:  9 years ago  
 
 
        Seen: 3,865 times 
 

        Last updated: Jan 07 '16 
 
 
 
 
 
 
 
 
 
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