Solar newbie
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You need to make an energy budget, list all consumer loads
Ideally in AH, estimate max minutes / hours used per 24 hours.
Another way - buy as much solar as you can fit, then size your battery bank based on that.
Where / when you travel is relevant, assuming you park in full sun.
Ideally in AH, estimate max minutes / hours used per 24 hours.
Another way - buy as much solar as you can fit, then size your battery bank based on that.
Where / when you travel is relevant, assuming you park in full sun.
lenny flank
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John is right--you are going about this backwards. You need to first determine how much power you will be using , then size your setup to that.
So, first you want to list all the things you want to use electricity for, how many amps each of them will use, and how many hours per day you plan on having them plugged in. That will tell you how much electricity you will need to produce each day.
Once you have that figure, take the number of amp-hours you will be using and double it. That is the minimum size AGM battery bank you will need.
To charge it, you need a minimum of 100 watts for every 100 amp-hours of battery bank. To be safe in winter or during cloudy days, double that figure. That will tell you how much solar capacity you will need.
Add a controller and an inverter.
As an example, my setup is a 100w solar panel and a 100ah battery. With that I charge my laptop, my phone, my camera battery, an electric razor, and the AA batteries in my hockey-puck LED lights. In summer that gives me plenty of power. In winter when the days are shorter, it gives me BARELY enough power--I would be OK if I had a 200w panel instead.
There are some people here who have massive systems--over 1,000 watts. That'll cost you a few bucks, though.
Most people alas have no idea how much electricity they actually use, since it all just comes from the wall in unlimited quantities. In a vehicle, they do not have that luxury--producing your own electricity in a vehicle is neither abundant nor cheap. It's a lot easier to cut back on your usage where possible than it is to produce more than you need.
So, first you want to list all the things you want to use electricity for, how many amps each of them will use, and how many hours per day you plan on having them plugged in. That will tell you how much electricity you will need to produce each day.
Once you have that figure, take the number of amp-hours you will be using and double it. That is the minimum size AGM battery bank you will need.
To charge it, you need a minimum of 100 watts for every 100 amp-hours of battery bank. To be safe in winter or during cloudy days, double that figure. That will tell you how much solar capacity you will need.
Add a controller and an inverter.
As an example, my setup is a 100w solar panel and a 100ah battery. With that I charge my laptop, my phone, my camera battery, an electric razor, and the AA batteries in my hockey-puck LED lights. In summer that gives me plenty of power. In winter when the days are shorter, it gives me BARELY enough power--I would be OK if I had a 200w panel instead.
There are some people here who have massive systems--over 1,000 watts. That'll cost you a few bucks, though.
Most people alas have no idea how much electricity they actually use, since it all just comes from the wall in unlimited quantities. In a vehicle, they do not have that luxury--producing your own electricity in a vehicle is neither abundant nor cheap. It's a lot easier to cut back on your usage where possible than it is to produce more than you need.
highdesertranger
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1. determine usage
2. size battery(s) to usage
3. size the solar to the battery(s)
don't buy Harbor Freight panels. highdesertranger
2. size battery(s) to usage
3. size the solar to the battery(s)
don't buy Harbor Freight panels. highdesertranger
Trebor English
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captain said:
Monocrystaline panels are slightly smaller than polycrystaline panels of the same wattage. Look up some on Amazon, write down length and width and multiply to get square inches. The amorphous Harbor Freight panels are much larger per watt. If you are setting them up behind the shed where size doesn't matter that's different from the roof of a vehicle where space is limited and you want low weight up there.
At Harbor Freight it's about $2 per watt. Polycrysyaline panels on Amazon are about $1 per watt.
The $200 kit at Harbor Freight could be done with a $100 panel and a $15 charge controller from Amazon. You can get a 25 foot spool of AWG #8 wire too.
Harbor Freight sells a cheap crimper and a box of a bunch of different crimp terminals that I have bought and used with success.
If you want to charge a phone and a lap top, run a fan, keep a led light on in the evening a 100 amp hour $100 flooded lead acid trolling motor battery and a 100 watt panel will do. If you have a tiny efficient 12 volt fridge that is in the maybe/maybe not area with only 100 watts. It depends on where you are, your temperature, the fridge temperature and use.
All of the technical jargon might as well be Greek to me. All I want is to be able to use a small fan, light, and laptop at night. The camper is solar ready, and I just have one Marine battery. It sounds like 100 watts is all I need, but should get 200W ideally, right? And Highdesertranger said not to buy Harbor Freight??
highdesertranger
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Harbor Freight panels are way over priced for the cheap junk they are. highdesertranger
Kia girl
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I have harbor freight solar because that is what I could get at the moment. It works for me. I run a 65 quart fridge, charge my devices, and run the lights that come with it. My batteries haven’t gone below 12.6 with them. I only have 105 ah worth of batteries.
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Spaceman Spiff
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captain said:
The frames on the HF solar panels I looked at were cheap and flimsy; too flexible.
The glass did not seem to be as thick as the glass on my Renogy panels.
I could not find any information on the quality of glass used; impact resistance or light transmission.
The seal between glass and frame was not good (watertight?).
I have had good luck with Renogy panels. 5 years and two bad hailstorms with no problems.
I found this from Back Country Solar: Zamp 80W portable folding suitcase kit. "provides 5 amps of charging power". $516. Can somebody tell me if this is a good idea for somebody who has a 2016 R-pod 171. I'm not solar savy so this one looks user friendly for me, a first time solar newbie. What will this system do for me?
jonyjoe303
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What will this system do for me? 80 watts will at most give you 4 amps in the best conditions. I notice from my everyday use that 20 watts gives you about 1 amp of power. You only see the best conditions for the few hours the sun is overhead.
below are some of the panels I had and there output.
kycora 120 watts (21 volt panel) about 6 amps with either pwm or mppt (mppt no advantage on low voltage panels)
sharp 240 watt (36 volt panel) 7 amps with pwm, 12 amps with mppt (up to 15 amps when charging lithium)
I always recommend to get the largest panel that will fit on your roof, you won't regret it. When I first started I got the small 120 watt panel it was very underpowered for my use. When I upgraded to the 240 watt I had serious power to use, there nothing better then having unlimited power. But even with 240 watts you at most will be trickle charging most lead acid batteries, but thats alot better then 6 amps.
There are always good deals on craiglist, I paid 200 dollars for my 240 watt panel, and I got a 20 amp ecoworthy mppt for 100 dollars. But you can use a cheap (less then 20 dollars) 15 amp pwm controller on the large panels , you just wont get the max amps it can put out. No need to spend big money to get a decent system.
Nothing complicated about solar, 2 wires from panel go to controller pv in, 2 wires from controller batt go to battery. Harbor freight panel operates on same principle. The panels you buy by themselves come with no wires, but that isnt expensive to buy.
below are some of the panels I had and there output.
kycora 120 watts (21 volt panel) about 6 amps with either pwm or mppt (mppt no advantage on low voltage panels)
sharp 240 watt (36 volt panel) 7 amps with pwm, 12 amps with mppt (up to 15 amps when charging lithium)
I always recommend to get the largest panel that will fit on your roof, you won't regret it. When I first started I got the small 120 watt panel it was very underpowered for my use. When I upgraded to the 240 watt I had serious power to use, there nothing better then having unlimited power. But even with 240 watts you at most will be trickle charging most lead acid batteries, but thats alot better then 6 amps.
There are always good deals on craiglist, I paid 200 dollars for my 240 watt panel, and I got a 20 amp ecoworthy mppt for 100 dollars. But you can use a cheap (less then 20 dollars) 15 amp pwm controller on the large panels , you just wont get the max amps it can put out. No need to spend big money to get a decent system.
Nothing complicated about solar, 2 wires from panel go to controller pv in, 2 wires from controller batt go to battery. Harbor freight panel operates on same principle. The panels you buy by themselves come with no wires, but that isnt expensive to buy.
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