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--- electrical:solar:frugal [2017/11/19 19:24]
frater_secessus [system sizing]
+++ electrical:solar:frugal [2018/06/16 22:17]
frater_secessus [Making do with tiny solar setups]
@@ Line 4: / Line 4: @@
+This page is more about making do with what you already have than about about what to buy if you are [[electrical:solar:gentle_intro|starting from scratch]].
 ===== system sizing =====
-Large solar installs are can be useful but are overkill (in size, output and expense) for many campers.  [[http://rvwiki.mousetrap.net/doku.php?id=electrical:solar:builds|100w and similar]] installs can work well, particularly [[electrical:12v:alt_and_solar|in combination]] with [[electrical:12v:alternator|alternator/"dual-battery" charging]].
+Large solar installs are can be useful but are overkill (in size, output and expense) for many campers.  Even [[http://rvwiki.mousetrap.net/doku.php?id=electrical:solar:builds|100w]] installs can work well, particularly [[electrical:12v:alt_and_solar|in combination]] with [[electrical:12v:alternator|alternator/"dual-battery" charging]].  [[electrical:solar:builds#w1|200w]] is the most common solar configuration on CRVL.
 Reduce the size of your solar install (panels, batteries) by running your loads [[electrical:solar:nonessential|when the system has power to spare]], not when it is trying to charge back up.
@@ Line 24: / Line 27: @@
 ===== charge controllers =====
+You can eek out a bit [[electrical:solar:pwm_tweaking|more power from PWM]] or [[electrical:solar:shunt_tweaking|"shunt"]] charge controllers by tweaking their setpoints.
@@ Line 30: / Line 35: @@
 ===== batteries =====
+First off: box store marine, dual-purpose or "deep cycle" batteries are [[electrical:12v:deep_cycle_battery#chain_store_batteries|not deep cycle]].  Can you use them if you already have them?  You bet.
-FIXME
+There is no magic way to increase the limited //performance// (capacity) of these batteries, but you can help them last longer.  Those with removable caps can be [[electrical:12v:charging#watering_batteries|watered]], which will extend their useful life.
+Drawing them down to only 80% State of Charge (also written as [[electrical:depth_of_discharge|20% Depth of Discharge]]) instead of deep cycle's 50% SoC may double their lifetime.  Secessus calls this [[electrical:solar:shallow_cycling|"shallow cycling"]].
+If you don't have a spare battery you can even [[electrical:solar:shallow_cycling|use your starter battery]] with various levels of success.
 ===== converter =====
+{{ https://www.circuitspecialists.com/content/image/110880/600/ps1-60w-sl12-0.jpg?200}}
+If you have an adjustable 12v power supply around you can make it into a dumb converter. In this pic the "pot" (potentiometer) is the orange plastic part near the connectors;  it's labeled Vadj for //voltage adjust//.  You can adjust output voltage((within reason, usually 10-15%)) by turning it with a small screwdriver.
+For deep cycling:  try setting it to a low Absorption voltage like 14v
-FIXME
+For shallow cycling:  try setting the output to a high Float voltage like 13.6v or so.

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