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opinion:solar:sizing [2022/05/24 15:12]
frater_secessus [days of reserve]
opinion:solar:sizing [2022/05/24 15:15]
frater_secessus [battery bank]
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 In general, bigger systems (higher wattage panels, bigger controllers, bigger battery banks) cost less per-watt-harvested. In general, bigger systems (higher wattage panels, bigger controllers, bigger battery banks) cost less per-watt-harvested.
  
-Broadly speaking, lithium chemistries are most cost-effective when the camping experience is expected to last for many years and the batteries stored inside.((Note that it is false economy to pay for 10 years of battery cycling (as with lithium) if one is going to wreck it in 2 years)).  For shorter projects (traveling around the country for  ≤3 years) in an RV with exterior battery trays the standard T-105 style FLA bank((like 2x 6v Trojan T-105 batts in series for 12v)) may be more cost-effective.  For very short installations ( ≤1 year) marginal batteries found at walmart may be fine. I encourage people to do the //$/kWh math for the situation// rather than relying on the latest trends or loudest voices. Horses for courses.+
 ==== days of reserve ==== ==== days of reserve ====
  
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 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.  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. 
  
 +Broadly speaking, lithium chemistries are most cost-effective when the camping experience is expected to last for many years and the batteries stored inside.((Note that it is false economy to pay for 10 years of battery cycling (as with lithium) if one is going to wreck it in 2 years)).  For shorter projects (traveling around the country for  ≤3 years) in an RV with exterior battery trays the standard T-105 style FLA bank((like 2x 6v Trojan T-105 batts in series for 12v)) may be more cost-effective.  For very short installations ( ≤1 year) marginal batteries found at walmart may be fine. I encourage people to do the //$/kWh math for the situation// rather than relying on the latest trends or loudest voices. Horses for courses.
  
 Having an **undersized bank** means //running out of power// at night.  Sitting in the dark at night with no fan.   Having an **undersized bank** means //running out of power// at night.  Sitting in the dark at night with no fan.  
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 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.  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. 
 +
 +
 +After figuring your rough capacity requirements, consider these factors:
  
 You will **need somewhat more Ah capacity** You will **need somewhat more Ah capacity**
opinion/solar/sizing.txt · Last modified: 2023/12/26 11:57 by frater_secessus