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--- electrical:solar:nonessential [2020/07/08 14:58]
frater_secessus [LVD + timer - eternal Absorption]
+++ electrical:solar:nonessential [2023/10/18 19:08] (current)
frater_secessus [when to run opportunity loads]
@@ Line 19: / Line 19: @@
 ===== when to run opportunity loads =====
-**The best time to run non-essential loads is when there is surplus current** over what battery charging needs.  This means **during Float, or after current has started dropping off in Absorption**.  For [[electrical:12v:deep_cycle_battery#lithium_chemistries|LiFePO4]] there is excess power any time after the bank has reached the intended charge state.
+The optimal time to run loads is when there is **power available in excess of battery charging requirements**.  When done at the right time, the loads are effectively run [[electrical:solar:offthepanel|off the panels]] rather than off the battery bank.  This results in the bank having a higher state of charge both at sundown and morning.
-Opportunity loads should not be applied during [[electrical:12v:charging|Bulk stage]] since Bulk, by definition, means the battery is taking all the available current.((assuming no charging limit has been configured in the [[electrical:solar:charge_controller|charge controller]]))
+With **lead** this means **during Float**, or **in late Absorption** when charge current acceptance has fallen enough that the system can run the loads //and still maintain the Absorption voltage setpoint//.
+There is a little more wiggle room with [[electrical:12v:deep_cycle_battery#lithium_chemistries|LiFePO4]];  the loads can be run with no net negative effect on a Lithium system when
+  * the bank has reached the intended charge state; or
+  * any time the bank can be //projected// to reach the intended charge state by sundown while carrying the extra loads. In effect, lithium allows you to "borrow" against future charging without penalty..   Exception:  Lithium setups with PWM [[electrical:solar:charge_controller|solar charge controllers]] will make [[electrical:solar:pwm_tweaking|most power]] when bank voltage is highest.  So waiting for Float or Absorption to run opportunity loads will mean the solar can make more Wh per day.
@@ Line 72: / Line 77: @@
 In this approach the LVD is set just below Vfloat as above, but activation of the loads is delayed by some amount of time.  Observation of the system during charging will suggest how long it normally takes takes charging amperage to drop off (ie, when the system has surplus current).
-Suggested delay for conservative opportunity loading == the time from [passing Vlvr setpoint during Bulk] to [completed charging].((settling to Float)).  This delay might be 2-3hours.
+Suggested delay for conservative opportunity loading == the time from [passing Vlvr setpoint during Bulk] to [completed charging].((settling to Float)).  This delay might be 2-5hours.
@@ Line 100: / Line 105: @@
   * [[hvac:dehumidifier|dehumidification]]
   * [[electrical:12v:laptop|laptop]] and phone charging
-  * rice cooker((http://www.cheaprvliving.com/forums/Thread-How-much-solar-do-I-need?pid=141508#pid141508))
+  * [[food:cooking:excess_power|cooking with small appliances]]

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