Automotive

Tesla driver builds folding rooftop array for parked solar charging

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The wood-framed Beta1 prototype currently gets around 20 miles of extra range for five hours under sunlight, but Omid Sadeghpour is working on an improved version that could bump that up to 75 miles
Dartsolar/Omid Sadeghpour
The wood-framed Beta1 prototype currently gets around 20 miles of extra range for five hours under sunlight, but Omid Sadeghpour is working on an improved version that could bump that up to 75 miles
Dartsolar/Omid Sadeghpour
The Beta1 prototype features nine 175-W panels mounted to a wooden frame
Dartsolar/Omid Sadeghpour
Telescoping tubes within the frame allow the panels to be folded away when it's time to drive
Dartsolar/Omid Sadeghpour
Omid Sadeghpour is working on a Beta2 version that's made from carbon fiber to reduce weight and height while also allowing for an increase in total panel capacity
Dartsolar/Omid Sadeghpour
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For the last couple of years, Omid Sadeghpour has been working on a fold-out solar array for his Tesla Model Y, which he reckons can get him up to 20 miles of range per day without plugging in. Now he's moving to an improved Beta2 version.

Electric vehicles used for the daily commute could spend much of their day sat motionless out in the open in a car park, perhaps with the Sun beating down on the roof. So why not put all of that solar energy to good use? That's the thinking behind Sadeghpour's Dartsolar project.

He's built a wood-framed Beta 1 prototype with Jeran Bruce at California's Forged Makerspace, with telescoping carbon-fiber tubes allowing nine 175-W flexible panels to be folded out when the vehicle is parked.

The array is said to weigh under 165 lb (75 kg) in total and is designed not to expand beyond a standard US parking space. The panel junction boxes are all stowed in the trunk at the moment, which the designer claims gives him the freedom to connect the panels in series or parallel, as well as removing bulk and weight from the rooftop installation. When it's time to drive on, the array can be collapsed down in under a minute to a rooftop box shape.

Telescoping tubes within the frame allow the panels to be folded away when it's time to drive
Dartsolar/Omid Sadeghpour

Sadeghpour reckons that the setup can reliably add around 6 kWh of juice to the battery per day via DC-to-AC-to-DC charging, which translates to roughly 20 miles (32 km) of solar-powered driving. But to be clear, this is very much a DIY project at the moment and is nowhere near ready for consumer release.

Beta1 stands quite high on the roof when folded – 11 inches (28 cm) to be exact – so will affect overall aero, but the team is currently working on a second prototype with a support frame made from carbon fiber that will stand around half that height in drive mode.

Beta2 (which is actually the fifth iteration) is expected to bump the wattage to 4,000 for up to 45 miles of range, though the team is also looking into DC-to-DC charging for "about 63 miles for a five-hour sun window."

According to a Reddit post from Sadeghpour last month, he intends to make the Beta1 blueprints and build files available via his Dartsolar website – where folks can also get project updates. The video below has much more detail.

Source: Dartsolar

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11 comments
vince
The inventor probably loses more miles in lost aerodynamics with the huge box on the roof than he would ever gain back from charging with sun.
Bob B
I hope the final version ends up being capable of being stored in the trunk while travelling so it doesn't ruin the aerodynamics of the vehicle. Currently it may add 20 miles per day of juice, but the worsened aerodynamics probably take a chunk of that back.
Korina57
Until it can be an integral part of the roof it's not a game changer. I'm surprised that a nefarious character has not tried possession of it.
guzmanchinky
Seems like a great idea, shade AND power. Just needs better integration.
anthony88
Might be more effective if government regulations required open parking lots install solar panel shelters that could be optionally plugged into for an additional charge.
Bodger
Right now the aerodynamics and look are not good but with a bit of tweaking and new materials I'm sure that they can be improved. Perhaps Thule could be brought in as consultants -- their long rooftop ski boxes are quite aerodynamic and I've not experienced a terrible economy hit with one on top of my Outback.
Bob809
anthony88 I was just thinking the same. Having worked in Saudi Arabia, there being lots of strong sunlight there, and having seen some covered areas on car parks, it would be a relatively simple matter to fit decent solar panels with a charging point for electric cars. Imagine, maybe you have a long battery depleting drive to work, and if there was charging at work it would benefit you a great deal. Even if you had to pay a SMALL fee for this facility, your life would be less stressfull on the way home. As for the project here, a Beta version thinking about aerodynamics/location of solar panels will be in the pipeline. Great idea anyway. Why has Tesla not thought of this already?
windykites
This rig would suit roll-out solar panels if they arrive on the market.
PeterMac
20 miles for 5 hours charging - assuming the sun is mostly overhead ! So assume 1000 - 1500 - is about the time it would take him to walk the 20 miles home
PeterMac
IKEA spain covers its vast car parks with solar panels. Quite a sight.