Solar Panel Roof Rack

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RolanDavison said:
It's a great way to use a renewable energy source to power your car and reduce your dependence on fossil fuels.
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Do you have a particular example in mind? It would have to be very large to provide a significant amount of power.

The $260K Lightyear0 was going to have a "solar skin", that the company claimed would give the EV up to 43 miles of range per day. Unfortunately, the production of that car was halted before producing a single car, so we'll never know how realistic that claim was..
 
The Subaru Solterras sold in Japan had the option of having a solar roof.

There are multiple companies working on solar windows (for buildings).
 
I did investigate a solar roof panel for my SE.
1. Would have made a contoured panel. Yes, this can be done. A flat panel on a rack has an enormous amount of drag. I know this from carrying sheets of ply etc on low powered ICE cars. It's like towing a parachute.

2. The L1 charging process has a parasitic draw and losses of a few hundred watts. This really, really hurts charge efficiency at low power.

3. The available charging rate. You cannot charge at all with less than 510W (6A, 85V). That's outside the specs for J1772.

You could use the solar panel to charge a small intermediate battery, then dump that in bursts into the car. This is the only way I can currently think to make it work. If I street parked without a charger, I'd be inclined to try that.

A ~1m2 roof panel could provide a few thousand miles of driving per year, depending on how much sun you get. Up to maybe 8-10 miles per day. But, it's something that is going to be very difficult to retrofit cleanly as it really needs it's own on onboard charging circuit. I'd happily pay extra to upgrade a moonroof car to a solar charge option, though. I suspect that there are quite a few low mileage drivers who find solar trickle charging a game changer. Think off grid, apartment dwellers and street parkers.
Others, like me, just wouldn't need to charge as often. I may just be able to commute with only weekend charging in the summer.
 
pictsidhe said:
You could use the solar panel to charge a small intermediate battery, then dump that in bursts into the car. This is the only way I can currently think to make it work. If I street parked without a charger, I'd be inclined to try that.
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I have a couple of Eco Flow Delta Pro batteries. Ecoflow has an accessory that lets you connect them together, resulting in 240V. I'll provide some photos when I get an EVSE.

The batteries have nice features (including inputs from solar panels).
 
Qisl said:
I have a couple of Eco Flow Delta Pro batteries. Ecoflow has an accessory that lets you connect them together, resulting in 240V. I'll provide some photos when I get an EVSE.

The batteries have nice features (including inputs from solar panels).
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I'm fascinated by the EcoFlow line. What is the capacity and what level of current can your particular pair of EcoFlow batteries deliver? Did you get them instead of an emergency generator or do you use them regularly to power things away from the grid? How heavy is each one of your pair?
 
The Delta Pro (LFP) is 3.6kW output (and 3.6kWh capacity) but if you pair it with a second one then it's 7.2kW output (with generator plug).

What I do like is the EV X-Stream Adapter that allows you to charge the battery via J1772 (up to 28A) so you could presumably lug that 100lbs beast to a free L2 charging station. Aside from that I'd still put the money towards solar PV + grid tied batteries for better value because there's the 30% IRA tax credit..then again I think you can apply the 30% tax credit for off grid setups as well.
 
insightman said:
I'm fascinated by the EcoFlow line. What is the capacity and what level of current can your particular pair of EcoFlow batteries deliver? Did you get them instead of an emergency generator or do you use them regularly to power things away from the grid? How heavy is each one of your pair?
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I purchased them because I live in Texas. Those batteries because I sometimes need portable power away from the house.

I currently charge them mostly for free at night, and use them during the day to power other stuff.

But, if you are really interested in battery backup for your house, get ones with a real warranty, from a company that has been around longer than a year or so.
 
Qisl said:
I purchased them because I live in Texas. Those batteries because I sometimes need portable power away from the house.

I currently charge them mostly for free at night, and use them during the day to power other stuff.

But, if you are really interested in battery backup for your house, get ones with a real warranty, from a company that has been around longer than a year or so.
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That gets really tricky because many manufacturers will set their warranty to the earliest of:
A. 10 years
B. # discharge cycles
C. Total energy throughput (charge + discharge kWh)

If one were to fully charge/discharge once on a daily basis, it would probably be done within 4 years.
 
A normally shaped car has too much drag to make a daily solar charge worthwhile.

I VHB taped a flexible 200 w panel on the roof of our Transit van to charge the 200 ah house batteries. It's difficult to get it to sit flush on a roof w multiple contours.
 
Loxodeyew said:
The actual mileage you'd gain from this setup would depend on various factors, including the size and efficiency of the solar panels, the weather conditions, and how much sunlight the car gets during those 9 hours. While I don't have the exact numbers for this specific scenario, it's a concept that has been explored in the realm of electric vehicles. Some solar roof panels can provide a modest boost to an EV's range, which can be helpful for daily commuting. If you're curious about the potential benefits and practicality of such a setup, you might want to check out solar energy Ireland for insights and experiences shared by others who have looked into harnessing solar energy for their vehicles.
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I'd suggest visiting InsideEVs' Aptera forum where @Kerbe keeps us up-to-date on the technology and progress of the Aptera EV, which will have PV cells covering its upper surface. The company is putting a lot of work into making their glass-covered cells reliable in the harsh automotive environment.

I was fascinated to learn that Aptera just removed some of the planned cells because those cells were underperforming due to their unfavorable locations--they just didn't receive enough sunlight. @Kerbe linked us to a ride-along interview with Aptera' solar engineer.
 
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