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opinion:frater_secessus:how_much_excess_solar_power [2022/12/14 13:51]
frater_secessus [system efficiency]
opinion:frater_secessus:how_much_excess_solar_power [2023/04/21 11:50] (current)
frater_secessus [Pareto summary]
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 DRAFT DRAFT
  
 +
 +FIXME
  
 ====== How much extra solar power do I have? ====== ====== How much extra solar power do I have? ======
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-===== Pareto summary =====+===== TLDR =====
  
  
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-===== empirical testing ===== +===== direct testing =====
- +
- +
-===== observation and prediction =====+
  
 +Plug it in and see if the solar can support it [[electrical:solar:offthepanel|without affecting the battery bank]].  Easy peasy.  
  
 +The downside is this is a YES/NO answer;  it tells you a specific load will run but does not tell you about how much power is actually available.  If you want to see the Bigger Picture then read on...
  
 +===== prediction =====
  
-==== overall system efficiency ====+==== looking up daily insolation (FSE) =====
  
-You can get feel for overall system efficiency by +Hours of Full Sun Equivalent (FSE) is convenient way to think of the amount of sunlight reaching the ground over the entire day.  4.5 hours of FSE means 4.5kWh of power reaching the ground per square meter.  
  
-   - watching your system over time, as described above +To predict daily harvest we will use
-   - comparing real-time harvest to theoretical harvest+
  
 +  * FSE
 +  * your panel wattage
 +  * and your system's overall efficiency
  
  
-===== average power harvest for a given time/place ===== 
  
-==== theoretical power available ==== 
  
-=== predicted daily harvest === 
  
  
 +==== calculating power available (W)  ====
  
-=== predicted harvest at a specific time === 
  
 Real-time harvest is a bit easier since there is no time component.  We are working in Watts (W) rather than Watt-hours (Wh). What we are doing is comparing the strength of sunlight reaching the ground (perpendicular) vs [[electrical:solar:output#zenith_angle|the cosine of the angle at which it actually strikes the ground]], or strikes a flat-mounted panel.  Real-time harvest is a bit easier since there is no time component.  We are working in Watts (W) rather than Watt-hours (Wh). What we are doing is comparing the strength of sunlight reaching the ground (perpendicular) vs [[electrical:solar:output#zenith_angle|the cosine of the angle at which it actually strikes the ground]], or strikes a flat-mounted panel. 
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 This cosine is [[https://www.esrl.noaa.gov/gmd/grad/solcalc/azel.html|calculable for a given time and place]].   This cosine is [[https://www.esrl.noaa.gov/gmd/grad/solcalc/azel.html|calculable for a given time and place]].  
  
-**Example**: if you have 200w of panels and calculated cosine is .70 then **140w of light is landing on your panels**. +**Example**: if you have 200w of panels and calculated cosine is .70 then **140w of direct light is landing on your panels** in clear skies
  
 ==== finding and using system efficiency ==== ==== finding and using system efficiency ====
opinion/frater_secessus/how_much_excess_solar_power.1671043869.txt.gz · Last modified: 2022/12/14 13:51 by frater_secessus