How much solar do I need?

[ALuckyDuck]

Thanks all for the insight. I had read the fans pull ~3amps, but I'll use 5 amps when making conservative estimates. I'm leaning on the side of a 200 watt set up, and will look into alternate sources of periodic higher amperage charging as per SternWake's recommendations.

 

[akrvbob]

If you go with a pair of flooded golf carts, you won't have to worry about the batteries ever again, 200 watts will keep them happy if you are reasonable in your use.

I don't worry about off-gassing, I think the risk is greatly exaggerated. But if you are, then just put them in a vented box and problem solved.

Why you should go with flooded golf carts:

1)They'll be much cheaper to buy,
2) Other than checking the water, they are much easier to maintain and keep healthy and happy!!
3) Unless you drive enough or have regular access to shore power, golf carts will last much longer.

I'd go with Renogy 200 watt kit and upgrade to a Renogy MPPT controller.
Bob

 

[ALuckyDuck]

I've been back and forth considering sealed vs wet cell. Even if the risk of wet batteries is over exaggerated, I just can't find any good deals on a pair of golf carts. The cheapest I see online would would be a pair of new 6vs 225Ah totaling $300+. Any recommendations for deals?

 

[SternWake]

Goto a golf course if one is nearby, they get pallettes. Are you near any boatyards, Sailors love their 6v GC's too, well the ones who have already figured out that 12v flooded batteries in deep cycle applications is a serious compromise.

Sams club and Costco sell 6vGC's made by johnson controls, They are not as great as Trojan t-105s but will still vastly outperform any flooded 12v battery in deep cycle duty.

There are a few true deep cycle 12v batteries, such as the Trojan t-1275, J150 or J185. These are taller and heavier. In reality these are the only flooded true deep cycle 12v jars that can come close to rivalling 6v GC batteries in deep cycle applications.

Search out battery distributors in your nearest big town. Batteries are not something you should buy over the internet. You could get year old batteries with only 75% of their capacity remaining, and have no recourse.

In person, you can check the date codes, voltage, bathroom scale, and if you really want to freak them out, whip out your Pocket hydrometer.

Note, I have no Idea if a pocket hydrometer exists , but I have busted out the bathroom scale and voltmeter and had the sales people send out the manager in pure fright of the madman.

 

[highdesertranger]

the guru has spoken. seriously good advice from stern. I am not sure where you are located but if you search around you should be able to find a specialty battery shop. I would start there. highdesertranger

 

[jimindenver]

look at craigslist in the area you are in. There are usually some good deals here but you may have to wait for the right deal. Right now the best deal here is new 147 AH AGM's for $125 and no core charge. I'm tempted to pick some up and make a system here at the house out of my excess panels.

 

[ccbreder]

Duracell branded, wet cell, GC batteries, made by East Penn are highly recommended. They are available in eastern US Sam's Club. Also where I bought mine, Batteries Plus Bulbs, a franchise. My 235 amp hours were $109 each. Note the agm are not recommended as deep cycle.

 

[BradKW]

Hey Bob! I'm curios about your signature saying "570 watts of Solar Panels". In Basics of Solar link, I believe I'd seen you say you had something like a 55w starter setup, then added 135w and were content with that?

What caught my attention though was the 570 watts...that's much higher than most of the basic use setups I've seen, and I'd like to know a) what uses up that much watts, and b) what batteries match 570wats production. Thanks much

 

[akrvbob]

Hi, I'm Bob and I'm addicted to solar!

The simple answer is, "It just kept growing!" I am a high power user; on a daily basis I use"

65 quart Whynter fridge
Laptop-cell phone-Jetpack-Booster a LOT during the day
Microwave everyday
19 inch TV and Satellite TV Receiver for 5 hours a day.
I give away power to anyone around who might need it.

That seems like quite a bit but I have so much solar and battery that it barely impacts my batteries. I can't remember the last time I saw them below 12.4 and below 12.5 is unusual. A week of rain won't keep me from watching TV, but I would stop using the microwave.

I'm a big fan of having all the solar you need and if you do then a 1:1 ratio of watts to AH. I have 6 lead acid golf carts with about 650 ah.
Bob

 

[TooManyDogs]

I finally hooked up the Renogy 100W portable kit (10A pmw controller) to a group 31 SuperStart battery from O'Reilly (I opted for a marine battery from there vs WM because it's manufactured be EastPenn rather than JCI). I plan on mainly using this to power a 45qt Whytner frig. I have a little powerpack, which I can plug in wherever power is available, to recharge my cell phone. I'm only getting between 2 and 3 amps today (checking between 11am and 1pm) on a relatively clear winter day in TN. I opted for the portable kit since I'm not on the road yet and not in my permanent vehicle. I'll probably have to add another 100W panel if/when I full-time.

I guess it shouldn't be too hard to wire in another 100W panel to the 2-(50)W portable kit?

 

[29chico]

I finally hooked up the Renogy 100W portable kit (10A pmw controller) to a group 31 SuperStart battery from O'Reilly (I opted for a marine battery from there vs WM because it's manufactured be EastPenn rather than JCI). I plan on mainly using this to power a 45qt Whytner frig. I have a little powerpack, which I can plug in wherever power is available, to recharge my cell phone. I'm only getting between 2 and 3 amps today (checking between 11am and 1pm) on a relatively clear winter day in TN. I opted for the portable kit since I'm not on the road yet and not in my permanent vehicle. I'll probably have to add another 100W panel if/when I full-time.

I guess it shouldn't be too hard to wire in another 100W panel to the 2-(50)W portable kit?

IIRC the system you have is rated at about 5.7 amps on the panel and the controller is 10 amps max.  So putting another 100w panel in parallel with the controller & panel you currently have would be over 10 amps of input.  You would be at risk of letting out the magic smoke from the controller...

 

[GotSmart]

I finally hooked up the Renogy 100W portable kit (10A pmw controller) to a group 31 SuperStart battery from O'Reilly (I opted for a marine battery from there vs WM because it's manufactured be EastPenn rather than JCI). I plan on mainly using this to power a 45qt Whytner frig. I have a little powerpack, which I can plug in wherever power is available, to recharge my cell phone. I'm only getting between 2 and 3 amps today (checking between 11am and 1pm) on a relatively clear winter day in TN. I opted for the portable kit since I'm not on the road yet and not in my permanent vehicle. I'll probably have to add another 100W panel if/when I full-time.

I guess it shouldn't be too hard to wire in another 100W panel to the 2-(50)W portable kit?

All you will need is a MC4

 

[TooManyDogs]

Two more things to save up for. Thanks for the info!

 

[GotSmart]

Two more things to save up for.  Thanks for the info!

$7 to be able to uncouple the wires.

 

[Sabatical]

I got a set of those and found i didn't need to use them. I am planning to put them on the free tarp at the RTR.

 

[TooManyDogs]

Why don't you need them? Can you just uncouple them by hand, or use some other tool? Use different connectors?

 

[Sabatical]

Yes i am able to uncouple them by hand. If i squeeze the tabs the pressure from the o-ring seal pops them apart.

 

[highdesertranger]

x2, I can uncouple mine by hand too. I always thought it was funny people saying you need a special tool. highdesertranger

 

[GotSmart]

That did not work for me.

 

[TooManyDogs]

Okay. I can too. Money saved!