RVwiki for vanfolk and others who live in vehicles

User Tools

Site Tools

Trace: • series_vs_parallel
electrical:solar:series_vs_parallel

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision 		Previous revision
electrical:solar:series_vs_parallel [2020/05/04 14:32]
frater_secessus [Series] 		electrical:solar:series_vs_parallel [2025/04/17 14:56] (current)
frater_secessus [Series]
Line 1: Line 1:
 ====== Series and Parallel solar arrays ====== ====== Series and Parallel solar arrays ======
  
-In general, parallel arrays of nominal 12v [[electrical:solar:panels|panels]] are used with [[electrical:solar:charge_controller#pwm]] [[electrical:solar:charge controller|charge controllers]] and serial arrays with higher nominal voltage panels and [[electrical:solar:charge_controller#mppt|MPPT]] controllers.+===== TL;DR ===== 
 + 
 +  * With [[electrical:solar:charge_controller#mppt|MPPT]] solar charge controllers and 12v house battery bank there is often //little practical difference between parallel and series solar arrays//.   
 +  * [[electrical:solar:charge_controller#pwm|PWM controllers]] run arrays of the same nominal voltage as their battery bank:  12v and 12v, 24v and 24v. 
 +  * //generally speaking//, parallel panels will perform better in [[electrical:solar:shading|partial shade]] than series. [but don't shade your panels in the first place -- secessus] 
 +  * as with other [[electrical:12v:parallel_serial|series/parallel arrangements]], series increases voltage and parallel increases current. 
 +  * series arrays can reduce capital costs in some circumstances 
 +  * series/parallel arrangements are described with ''xPxS'' nomenclature: 
 +    * 2 panels in parallel would be 2P1S 
 +    * 2 panels in series would be 1P2S 
 +    * 4 panels in series-parallel would be 2P2S
  
  
Line 11: Line 21:
     * higher PV voltage can run in relatively **thinner wires** to the charge controller     * higher PV voltage can run in relatively **thinner wires** to the charge controller
     * serial connections can provide **some charging in low light situations** where lower voltage parallel or single-panel connections might not.  Imagine two nominal 12v panels running at 11v at sunrise;   the series arrangement might yield ~22v (battery charging) instead of 11v (voltage too low to charge battery).  Note that power harvestable at those times may be quite low.      * serial connections can provide **some charging in low light situations** where lower voltage parallel or single-panel connections might not.  Imagine two nominal 12v panels running at 11v at sunrise;   the series arrangement might yield ~22v (battery charging) instead of 11v (voltage too low to charge battery).  Note that power harvestable at those times may be quite low. 
-    * higher-voltage serial configurations with MPPT controllers may provide [[electrical:solar:shading#exceptionhigh_voltage_strings_mppt|more power under partial shading]] +    * higher-voltage serial configurations with MPPT controllers may provide [[electrical:solar:shading#exceptionhigh_voltage_strings_mppt|more power than parallel under partial shading]]. This is highly controller-dependent. 
     * higher voltages **work well with MPPT controllers**     * higher voltages **work well with MPPT controllers**
     * higher voltages can **charge higher voltage battery systems** like 24v.     * higher voltages can **charge higher voltage battery systems** like 24v.
     * more efficient than parallel when **mixing PV of same Imp but different Vmp**((https://www.youtube.com/watch?v=JfzT8u205co))     * more efficient than parallel when **mixing PV of same Imp but different Vmp**((https://www.youtube.com/watch?v=JfzT8u205co))
     * slightly better than parallel when **mixing PV of different Imp //and// Vmp**((https://www.youtube.com/watch?v=ZAKTMSEHfk8))     * slightly better than parallel when **mixing PV of different Imp //and// Vmp**((https://www.youtube.com/watch?v=ZAKTMSEHfk8))
 +    * higher voltages can help overcome minimum delta requirements to get the MPPT algo running (Victron controllers, for example,  require +5v to start and +1v to maintain MPPT). 
   * CON   * CON
     * series arrays can generate quite **high operating voltages**.  Be sure your controller can handle the VoC with edge effect.     * series arrays can generate quite **high operating voltages**.  Be sure your controller can handle the VoC with edge effect.
Line 41: Line 52:
 ===== Series-Parallel ===== ===== Series-Parallel =====
  
 +Consider this scenario:
 +
 +
 +  * 4 panels 
 +    * 150w
 +    * Vmp == 19v
 +    * Voc == 22.8
 +    * Imp == 7.9A
 +  * MPPT controller with 60v maximum input voltage
 +
 +A fully-series configuration ([[electrical:12v:parallel_serial|1p4s]]) would have a **Voc of 91.2v**, greatly exceeding the controller's input spec of 60v, and it's common to want to have 20% voltage headroom above Voc. 
 +
 +A fully-parallel configuration (4p1s) would require 3x 2-into-1 MC4 adapters or 1x 4-into-1 adapter.  The wiring from the array would need to carry 30A+ to the controller,  necessitating heavier wiring that would cost more and might not even fit the controller terminals.  It might be unable to charge at all under extreme low-light conditions. 
 +
 +A compromise might be series-parallel array (2p2s) with 45.6Voc and ~16A.  This would require 1x 2-into-1 MC4 adapter to combine the two serial strings.   Voltage is low enough for the controller, but high enough to allow low-light charging and the use of lighter wiring. 
 +
 +===== further reading =====
 +
 +  * [[https://www.explorist.life/solar-panels-series-vs-parallel/|Solar Panels – Series vs Parallel]] by Explorist Life
 +  * [[https://www.youtube.com/watch?v=1s2gsKWqyjM|How To Wire Solar Panels In Series vs Parallel -- For Beginners]]
 +  * [[https://www.cruisersforum.com/forums/f14/shading-serial-vs-parallel-this-time-with-data-284237.html|testing series vs parallel in a marine environment]]
  
electrical/solar/series_vs_parallel.1588602769.txt.gz · Last modified: 2020/10/11 23:48 (external edit)

Page Tools

affilliate disclosure | the RVwiki runs on a virtual server from NetCup

Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 4.0 International
CC Attribution-Noncommercial-Share Alike 4.0 International Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki