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opinion:solar:sizing [2022/05/24 15:10]
frater_secessus [controller sizing]
opinion:solar:sizing [2022/05/24 15:12]
frater_secessus [days of reserve]
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 [[lifestyle:words_of_wisdom|Words of Wisdom]]:  "You have to build for winter, and figure out what to do with the extra electricity in summer." -- timselectric((https://diysolarforum.com/threads/less-than-perfect-off-grid-system.35869/post-450655)) [[lifestyle:words_of_wisdom|Words of Wisdom]]:  "You have to build for winter, and figure out what to do with the extra electricity in summer." -- timselectric((https://diysolarforum.com/threads/less-than-perfect-off-grid-system.35869/post-450655))
  
-====== solar sizing - the Big Picture ======+====== power system sizing - the Big Picture ======
  
 There are many [[electrical:solar:sizing#calculators|calculators where you can plug in the numbers]].  This page is a 35,000ft view of how choices affect what you will need.  There are many [[electrical:solar:sizing#calculators|calculators where you can plug in the numbers]].  This page is a 35,000ft view of how choices affect what you will need. 
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 Your **reserve requirements** will profoundly affect the size, complexity, and cost of the system.   Your **reserve requirements** will profoundly affect the size, complexity, and cost of the system.  
 Sizing for an overnight camping trip is easy;  sizing for a three day trip a challenge;  sizing for a long trip or full-time vandwelling is serious business.  See the bottom of this article for example configurations.  Sizing for an overnight camping trip is easy;  sizing for a three day trip a challenge;  sizing for a long trip or full-time vandwelling is serious business.  See the bottom of this article for example configurations. 
 +
 +===== battery bank =====
 +
 +Once you know your daily power and reserve requirements you can spec out a battery  bank.  The capacity and chemistry of the bank will drive much of the charging section below. 
 +
 +
 +Having an **undersized bank** means //running out of power// at night.  Sitting in the dark at night with no fan.  
 +
 +Having an **oversized lead bank** for your charging ability results in [[electrical:batterycide|battery murder]] and replacement.  Having an **oversized lithium bank** is $$$ and can strain the alternator if [[electrical:12v:b2b|a current-limiting isolator]] isn't used.
 +
 +IMO, with lead chemistries((flooded, agm, gel)) it is better to have an undersized bank you can charge //fully and consistently// rather than a bigger bank you cannot charge. 
 +
 +You will **need somewhat more Ah capacity**
 +
 +      * if you have undersized solar
 +      * you have lead-chemistry battery bank
 +
 +You will need **somewhat less Ah capacity**
 +
 +    * if you run loads in the daytime instead of at night
 +    * if you have [[electrical:solar:overpaneling|oversized solar]]
 +    * you have lithium-chemistry battery bank((can be ~0.62% the size of the lead bank, due to deeper [[electrical:depth_of_discharge|DoD]].))
  
  
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- 
-===== battery bank ===== 
-Having an **undersized bank** means //running out of power// at night.  Sitting in the dark at night with no fan.   
- 
-Having an **oversized lead bank** for your charging ability results in [[electrical:batterycide|battery murder]] and replacement.  Having an **oversized lithium bank** is $$$ and can strain the alternator if [[electrical:12v:b2b|a current-limiting isolator]] isn't used. 
- 
-IMO, with lead chemistries((flooded, agm, gel)) it is better to have an undersized bank you can charge //fully and consistently// rather than a bigger bank you cannot charge.  
- 
-You will **need somewhat more Ah capacity** 
- 
-      * if you have undersized solar 
-      * you have lead-chemistry battery bank 
- 
-You will need **somewhat less Ah capacity** 
- 
-    * if you run loads in the daytime instead of at night 
-    * if you have [[electrical:solar:overpaneling|oversized solar]] 
-    * you have lithium-chemistry battery bank((can be ~0.62% the size of the lead bank, due to deeper [[electrical:depth_of_discharge|DoD]].)) 
  
  
opinion/solar/sizing.txt ยท Last modified: 2023/12/26 11:57 by frater_secessus