ThankYouJerry
New member
Can anyone please help me determine how many watts of solar panels will be sufficient for my needs? I'm planning on using a flexible solar panel affixed to my Thule Box and another flat mounted flat on my roof if necessary. I've found 50W, 100W, and 120W flexible solar panels to choose from (HQST, Renogy, and King Solar).
Typically, I will be camping from May-Sept on the West Coast. Mostly sunny but sometimes coastal clouds and/or partial shade. Of course, I understand that aiming/direction/cooling of the panels affects their performance.
Right now, with just my 2 aux bats (100ah each), I can sit for 48-72 hours max before they need charging depending on ambient outside temps, power usage, etc. I'd like to be fairly autonomous and not have to rely on driving or shore power to recharge my aux bats every 48-72 hours. However, I also don't want to spend more on solar panels than I have to. I've been hoping that 100-150W of solar panels will be enough.
Here are my parameters:
Reserves:
Aux Battery Bank (independent from a separate starter battery):
2 DieHard Platinum AGM (100ah each)
Draws
Propex 2211
Nominal voltage: 12V d.c.
Operating range: 10.0V d.c. min. to 15V d.c. max.
Maximum current d.c. gas operation: 1.7 Amps (0.01Amps on standby)
ARB50 Fridge
1.40 amps per hour
Plus:
1-2 LED interior lights 1-2 hours per day
In dash stereo (used rarely 1-2 hours per day)
2 iPhones charged 1x day each
1 iPad charged 1x day
2 Goal Zero Mini Lanterns charged 1x/day each - Cell Capacity: 11.1 Wh (3.7V, 3000mAh)
Which controller PWM or MPPT?
I've read that PWM controllers are best for systems under 200W and that sizing the PWM controller to the system is less important than with MPPT controllers. However, I've also read that MPPT controllers deliver more amps especially on cooler and/or overcast days.
Final (Dumb) Question...
Because I'm such a noob... Does the solar panel stay connected through the controller to the batteries even when I'm driving (charging with the alternator) or do I have to throw in a switch that keeps solar panel charging independent from alternator charging?
Typically, I will be camping from May-Sept on the West Coast. Mostly sunny but sometimes coastal clouds and/or partial shade. Of course, I understand that aiming/direction/cooling of the panels affects their performance.
Right now, with just my 2 aux bats (100ah each), I can sit for 48-72 hours max before they need charging depending on ambient outside temps, power usage, etc. I'd like to be fairly autonomous and not have to rely on driving or shore power to recharge my aux bats every 48-72 hours. However, I also don't want to spend more on solar panels than I have to. I've been hoping that 100-150W of solar panels will be enough.
Here are my parameters:
Reserves:
Aux Battery Bank (independent from a separate starter battery):
2 DieHard Platinum AGM (100ah each)
Draws
Propex 2211
Nominal voltage: 12V d.c.
Operating range: 10.0V d.c. min. to 15V d.c. max.
Maximum current d.c. gas operation: 1.7 Amps (0.01Amps on standby)
ARB50 Fridge
1.40 amps per hour
Plus:
1-2 LED interior lights 1-2 hours per day
In dash stereo (used rarely 1-2 hours per day)
2 iPhones charged 1x day each
1 iPad charged 1x day
2 Goal Zero Mini Lanterns charged 1x/day each - Cell Capacity: 11.1 Wh (3.7V, 3000mAh)
Which controller PWM or MPPT?
I've read that PWM controllers are best for systems under 200W and that sizing the PWM controller to the system is less important than with MPPT controllers. However, I've also read that MPPT controllers deliver more amps especially on cooler and/or overcast days.
Final (Dumb) Question...
Because I'm such a noob... Does the solar panel stay connected through the controller to the batteries even when I'm driving (charging with the alternator) or do I have to throw in a switch that keeps solar panel charging independent from alternator charging?
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