Solar panel setup questions.

[oil pan 4]

Problem with laying panels flat is they only produce about 50% of rated power. Actually more like 40% in the winter and maybe 60% in the summer.
Then the PWM charge controllers only let 2/3 of what the panel produce through to the battery. So in the winter you can be getting as little as 24% of a panels rated power.
Using a PWM charger on a vehicle based system is a waste of time and money.
But if you use a MPPT controller you get around 98% of what the panel produces.

[freebeard]

PWM = Pulse Width Modulation

MPPT = Muppet?



Imagine Arcimoto ships product and you get one and it has a [thin film] solar panel on the Omega door. Then about sunset you roll it into the ditch heading North. You could open the door and recharge your phone while you wait for the tow truck.

Notice the linkage. It has two straight arms and then one with an elbow.

[M_a_t_t]

So I'm thinking using a setup up like this (sketch uploaded)
1. (just the roof rack shape)
2. (cut away of cap). Use the rack to mount a box that holds the batteries charger, the whole set up pretty much. Mount the top of the cap to the box. With the panels angled I would be able to get more sunlight as long as I parked accordingly.
3. make panels in the top to mount the. panels to a "door" of sorts hinged on the front that opens up to the inside of the box, in case maintenance,whatever. Future mod maybe: make 2 doors inside the maintenance door so I can angle the panels to one of the two sides. They wouldn't allow access to the inside, using a panel underneath to keep it seperate.

I'm thinking maybe wood to build the cap from, for now atleast because I'd imagine it would be pretty heavy, wood would be easier to work with, and cheap.
Not decided on the batteries or the other pieces, but I'm going to order the 2 100w panels from home depot.

The way the doors open on the Arcimoto are interesting, I was just gonna start with a prop rod, maybe future mod Auto tracking?
I'm not exactly sure what I'll power with these. I know I'm going to get an inverter, maybe start with a tv but

[DragBean]

Keep the original battery. It will definitely keep it charged all the time.
In fact I'd recommend people do the solar mod when they otherwise would have to do their battery cuz it will help condition it better and ensure you got starting charge.
I have a 260 Watt panel that I modified by messing with the diodes and running two hot wires from it to not need a charge controller.
Actually made the car more aerodynamic too.

[freebeard]

Tiny little pictures.

Is the charge controller beneath the panels in the rack 'corral', or ahead of the rack?

With a prop rod at the center front and back you could latch/hinge it to either side, you have two choices and it wouldn't have to lift as high.

When you decide that wood is too heavy there is PolyMetal. It weighs 1/10th as much. And it's pre-finished.

For load? An LED light bar across the front, and a 110v AC outlet.

[DragBean]

You can figure out how to half the voltage from a cheaper 250 W residential panel and eliminate the need for a charge controller.

[oil pan 4]

MPPT means Maximum Power Point Tracking.
Almost no one uses trackers and I don't think any one uses them on a passenger vehicle.
An MPPT controller is better.
200 watts of solar installed, producing around 100 watts is usually a lot for a vehicle.

Do not run with out a charge controller unless you want to fry your battery or damage electronics. Running no charge controller is a rookie mistake.

[M_a_t_t]

I bought the 2 100w panels from home depot. $236 after tax. $1.18 per watt
Looking at either windy nation controller, can use for AGM SLA, Deep Cycle wet lead acid, Gel Cell or lithium batteries (12, 24, and 48V system
OR
Sealed, Gel, and Flooded battieries (12, and 24V systems)
I think I'm going to wait on buying a controller until I know what battery kind I'm going to get.
Undecided on the battery. The volt pack would be awesome, I was worried that because of the balancing it would need a special charger but this ( in the description) "available with installed BMS for balancing, and overcharging protection" sounds like I wouldn't need anything, just hook up to a regular charger.
Otherwise I'm just looking at regular SLA batteries or Deep cycle

FreeBeard: I was thinking inside. Does the location really matter? (about the charge controller)
PS: I resized the images.

[freebeard]

Thanks. I interpret that as a hinge at the front and a pair of hinge/latches to either side. That would be a very flexible set-up.

I was thinking of what you could do without a penetration through the roof. Instead of a LED light bar you could have a 'hood ride VW' style driving light;


http://www.pictaram.com/media/1206933857952304902_2150582274

...and a 110v outlet at the back. I've only experimented with PolyMetal, this was maybe $10 worth of scraps:



This was sheared, braked and rolled by hand, with an 18" lever arm. The nice thing is it's prefinished (I think it had a peel-off paper coating) so once it's shaped You're done.

What size would the four pieces be to en-blister the roof rack?

[vskid3]

Originally Posted by M_a_t_t

I'm not exactly sure what I'll power with these. I know I'm going to get an inverter, maybe start with a tv but

You're adding solar on a tight budget and you don't know what you'll be powering with it? Isn't that kinda putting the cart before the horse? I would wait on the controller and battery until you decide what you're going to be powering. If you do an alternator delete, you'd probably be alright with adding a battery similar to what the van uses for extra capacity (unless you drive with your lights on a lot or the stereo blasting). If you'll be living or camping in the van, you'll want to figure out what devices you'll be using and how much power they'll need. Lead acid batteries don't like being deep cycled, so for max life, you only want to use about the top 50% of the charge. Lithium can be a good route to go if you want a lot of capacity, but not the weight or size.