A way to charge directly from solar panels mounted to a roll bar

[smack daddy]

I have some ideas as to what I would like to do to the truck. I want to place flexible solar panels to the roof and panels to a custom roll bar that I am going to build. I wish they were making 4 wheel drive version. I am going to build an off road version and 31 X 10.5 tires will eat a lot of juice.

 

[cadblu]

Fisker has implemented this on production Ocean models, don’t know how well it worked, but look where they are now. They claimed it can add up to 2000 miles of extended range over the course of a year under ideal sunny conditions e.g. FL

 

[smack daddy]

I know it won’t give a complete charge however when I am working 12 hrs and it is just sitting there it would be nice to get a couple extra miles.

 

[E90400K]

Sounds like a job for Marco over at Donut Labs... or is it Asilab?

 

[beatle]

I think this idea has been brought up on almost every EV forum, but the answer is similar. Even on larger vehicles with room for a lot of panels, they don't provide enough juice to the battery to be worth the investment to integrate them with the vehicle. Even if the Fisker proposal were true, the math doesn't pan out:

2000 miles / 3 miles/kwh = 666 kwh per year * $0.18/kwh average cost in US = $120/yr return. That's in ideal Florida conditions. If you garage your truck, live somewhere that gets poor sun coverage, or have smaller/fewer/less efficient panels than the Ocean, that return plummets. Even under those perfect conditions, you're only getting about 5-6 miles per day of range. It can be expensive to implement panels like this for very little gain. I was surprised to see Fisker do that on the roof. I think it was largely just for show.

 

[SparkYellow]

Energy can be stored for later use. For most off grid folks, solar charging batteries is like putting gas in jerry cans. It is there when you need some. The juice is not much for charging the car, but is plenty to run small appliances and etc.

 

[beatle]

Don't get me wrong, I think solar is an invaluable way to power things off grid. I have solar panels on my shed that is not grid tied. My setup is pretty simple, but it's perfect for my needs. Putting the panels on the truck to charge it, however, just doesn't seem like a worthwhile application for all but the most fringe cases. There's just not that much power to be gained from such a small array.

 

[sodamo]

The ability to incorporate solar for accessories is my desire.

 

[KevinRS]

Part of the problem is how much are panels going to reduce the range through drag and added weight. Drag would be the big part. Even just a few percent reduction in range overwhelms the gains from the solar panels unless it is literally sitting in the sun all the time and making very short trips every few days.
In that case, put some panels next to the truck, angled to the sun. Horizontal panels are losing 15-25% just by being flat.

 

[JoeUser]

As others mentioned, it sort of cool, but makes no sense. But this is more or less how it’s normally done:

panels > separate buffer battery > inverter > charge port

Plenty of losses , but it’s the only economical way.