Feasability of going from gas to only electric

[Stubby79]

Hmm.

Did you check out how many watts per square foot you get with solar panels?

Quick googling gets you at ~15w/sqft. Where are you going to find 1000 square feet of surface?

I'm sure there are better ones on the market than that, but still...not the 10x more powerful ones you would need.

Have a look at the solar racers - all solar powered "cars" - or whatever they're called...those things are only running on a couple of hundred watts, at a guess.

Most solar panels you buy off the shelf are massively over-rated in the watts department. I bought one, read the fine print, then returned it. Their math works like this: Multiply the open circuit voltage times the short-circuit amperage and that's how they get at "100" watts. They will never produce that in reality.

[sendler]

Originally Posted by Stubby79

I'm of the opinion that solar panels are a losing battle...

Yeah. Even for for a fixed installation it is still fairly expensive without substantial subsidies. For range extending an EV, this whole thread has gotten quite dreamy. Solar is completely out of the question for charging while traveling in an EV. Somebody needs to look at the surface area required. It is ridiculous to continue this.

[oil pan 4]

You need at least 220w worth of panel for every 1kwh you hope to collect per day.

The flexible 100 watt panels I have measure about 30x40 inches. Multiply that by at least 120 to get 5kw.
I would bet on a generator and fuel as opposed to solar panels and sun for this application.

You might just want to get a generator trailer.

All off grid solar people have a backup generator. Or at some point they kill their batteries and/or go without any power.

Cheap made in China department store panels use OCV times short circuit amps to figure their over rating.
Reputable manufacturers use working volts times working amps.
So they are not over rated nearly as badly.

[thingstodo]

Originally Posted by Isaac Zackary

I realize that. But I was thinking of a portable solar charger and the pride of taking my Leaf over mountain passes that no one else would ever think of taking a Leaf. Even 1.5kW might save me from calling a tow truck

This is the lightest panel that I have seen (at least domestically). Not exactly cheap ...

EVTV Motor Verks Store: Flexible Solar Panel 200w, Solar, Boat and Golf, 200wsolarpanel

5000W = 25 of those, at $400 each, is $10K. Plus the space to lay them out and the wiring to connect them and the charge controller. Even these are over 7 lb each. 25 of them is under 200 lbs but it won't be with all of the other stuff you need.

1500W is much more manageable.

These are set up to glue down to the top of a golf cart sun shade, or a boat. At least one guy has plastered them over the hood, roof and trunk of his car. But that's only 3 panels = 600W. I have not seen anyone put them on the sides/doors as yet.

I would think a trailer would work. Maybe have the frame of the trailer support the panels and give you some rough adjustment for angle. 5000W, 25 panels, roughly 5 feet x 2.5 feet each ... 7.5 x 40 feet gets you 24 of them. Maybe stored on rigid frames as 7.5 feet wide, 10 feet long, 3 x 2 = 6 panels per frame. Hinge them together and flip them out to ...7.5 feet wide and 40 feet long is a bit cumbersome

I assume that one 'layer' of solar panels is exposed, even when things are folded up, so you would be generating while driving or parked during the day. It would be worth it to optimize the space and the hinging to use as much of the 8 foot normal trailer width as you can. There would be a lot of design trade-offs around how long to make the trailer 'folded up' ... or maybe you'd just limit the panels to 7.5 feet wide and 20 feet long and get rid of the hinging complexity. That would get you 12 panels at 200W for 2400W max charging ... 36V at MPPT gives you 360V into your pack. Not quite enough to charge the Leaf. But they go to almost 44V open circuit, so you should be able to connect your charge controller output to your 400V pack directly (well, through a disconnect, fuses, etc but no DC/DC boost converter required)

20 feet long should fit into a normal parking spot ... so you can park beside it overnight

[sendler]

Originally Posted by thingstodo

5000W = 25 of those, at $400 each, is $10K.

We are still talking a portable solar grid to charge an EV during a trip? That would make an array 17 feet on a side and take all day on a perfect day to drive for another hour.

[oil pan 4]

That's solar for you.

[Isaac Zackary]

For an example, I can get 1kW of DIY solar cells with tabs, solder and flux for $260.

1KW WHOLE 3x6 Solar Cells DIY KIT TAB Wire, BUS, FLUX | eBay

That's 26¢ per watt. A 6kW system would cost only $1,560. Now when compared to a $5,000 5,000W generator, that's not bad at all!

Of course that price could go up drastically depending on what I use to make the panels or of. And I'd want to make them as light and thin as possible. And then have a way to easily set them up.

Another option would be 22-21% efficient Maxeon cells. But those would be closer to $1 per watt, not including solder and such and seem hard to get in large quantities.

100 Pcs A Grade 21% Sunpower Solar Cells 5x5 Maxeon C60 For Flexible Solar Panel | eBay

[Isaac Zackary]

Originally Posted by sendler

We are still talking a portable solar grid to charge an EV during a trip? That would make an array 17 feet on a side and take all day on a perfect day to drive for another hour.

17 feet? What do you mean? I estimate on an 8ft wide trailer that every 10ft is about 1kW. So if it's 20ft it would be 2kW. Then let's say it was three 8' x 20' panels stacked on top of each other that I could slide out and turn into a 6kW array. Of course on a cloudy day that could be as little as 10%, or 600W. Also, could you imagine towing an 8' x 20' trailer with a Leaf!

Or I could make 24 4' x 5' individual solar panels. If they're 1" or less thick that could fit in the Leaf.

[Stubby79]

Test the output of one of the panels you're thinking of using before committing to more.

[Isaac Zackary]

I asked a few questions about Hybrid Industries Tech's 48kWh Nissan Leaf conversion and their answer was:

I only answer questions to potential customers.