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It's easy to dismiss this as green washing, but there is some value to it for city cars. The amount of electricity generated is never going to be enough to fully power the car, but that's not really the point. If having solar panels on your car roof means you can avoid charging much in summer, that will make owning an electric car for people who live in cities much simpler - and so support adoption.
As a back of the envelope calculation, if you covered the ~2.44 m2 roof of a VW ID3 with solar panels you'd probably see somewhere in the region of 244 kWh / year (based on typical UK solar panel generation per year - this would be more in a sunny place). At 4.3 miles/kWh that gives you just over 1000 miles / year of self charged driving.
It's true that those same solar panels would be more productive in a static installation. But it's also the case in the west that the biggest cost to solar rollout is installation, not the panels themselves. Putting panels on the roof of a car can be done in a factory, with none of the tricky site-specific work that makes costs balloon.
In fact, Hyundai are already planning a solar roof option with their Ioniq 5 (https://interestingengineering.com/hyundai-unveils-charger-o...). It will be interesting to see if that has any impact for the typical driver.
This topic came up on the recent Joe Rogan with Elon Musk. Elon said they considered it, but in the end it is just not worth it. He said there is just not enough surface area on a car to contribute a worthwhile amount of electricity.
The numbers quoted for this particular vehicle are very optimistic I think. If you’re lucky, you might get 5 miles a day out of it. What happens if it’s cloudy or rainy for a week? Or you park in a garage? There are so many variables, and the return on investment will be highly variable.
Tesla decided it’s just not worth the extra cost and complexity, for such a small return. I agree the idea sounds nice, but I’m afraid these companies that are doing are this, are mostly just getting a nice PR boost.
There is just no way around the technical limitations of solar panels in the amount of energy they can convert, and the surface area of a car. Vans or RVs that could fold out a larger array when parked might be another story.
I will say, it looks like they have some real innovations in the design and engineering of integrating the panels in the body. Looks pretty cool, so that’s not nothing:)
this is nothing but BS. There's so much BS that it's hard to know where to begin. The PV panel power output per square meter is a good place to begin. It's telling that they aren't comparing to standard, off the shelf PV panels which put out over 200 W/m2 as standard. Higher values are commonplace these days. And mind you, that figure of 200 W/m2 is at peak power levels which occur infrequently, often only an hour or two per day at the height of summer.
Second, this idea of "charging" ignores a very real issue with cities - shading and latitude. Even if every single car on city streets had PV panels, it is always going to be less technically and financially efficient when compared to rooftop solar which has the benefit of being at a higher elevation and being able to produce more energy. Most cities with the combination of wealth and population required for something like this are not at the equator, they are not even close to the tropics. They are further north. Shading is a bigger problem there as houses of even 5 - 10 m in height cast long shadows.
Edit - sad to see that people here will take EV manufacturer's words as gospel and will downvote critical comments. Good luck to anyone purchasing vapourware such as this.
Or you could cover every residential building and parking lot's rooftop with solar panels and have charging stations for cars, and low cost electricity for the entire block, neighborhood, and city.
This problem of "energy" in particular electricity, can be solved, but requires buy in from millions of different parties (HOAs, building owners, real estate developers). Unless the law changes where you can compel / force these stake-holders to adopt solar panels, change will never come at scale in urban areas. It's possible, it just requires so much buy in from so many individual entities.
Indeed, I were once skeptical (remembering EEVBlog's Solar Roadways series) but it really seems a good deal. Short commutes in cities can probably be covered. And a killer feature to me: if you ever get stranded somewhere without power, you at least have the option to wait a day or two to charge and get to somewhere nearby with power (around 3 miles/day for ioniq, 10 miles/day average for sion according to the articles).
Of course, smaller cars will probably have a better surface-energy consumption ratio, I don't expect to make much of a range difference for larger and utility vehicles. It's something I'd add to offroad vehicles just for the cool factor (of independence), even if the range added per day isn't significant in that case.
If having solar panels on your car roof means you can avoid charging much in summer
Some variation of this comes up every time: “but even a little bit helps” without knowing how little it is. I’ve got a Nissan Leaf. I’ve also got an RV with 400W of solar on top. That’s enough solar to keep things running all day on a reasonably sunny day. Unless you want to run the 1100W microwave, which you can run for fifteen or twenty minutes before you get to start over. Or you could drive an electric car for five minutes.
All this “doing the math” assumes perfect efficiency, blah, blah, to barely come out making it maybe kinda worth it. In the real world of cloudy days and off-angle sunlight, you’re better off having a sun roof put in and charging off your home’s solar panel. Or to put it more bluntly, until solar panel efficiency goes way up, panels on top of the vehicle is just dumb.
In a city, since everything is at most a few miles away, one shouldn't need a car to get around. Just put some trams/electric buses and bike lanes around. There, now you've removed about half the cars in the world.
The Ioniq 5 also come with a Vehicle-to-Load or V2L. This V2L port can charge other electrical appliances including EV cars as well. Since the charging time is very fast for the car itself (16 minutes to 80%), it is very interesting concept that perhaps can enabled Uber like mobile on-demand car charging fleets service that can come to charge EV cars on the road that low on battery [1].
[1]https://electrek.co/2021/03/03/hyundai-ioniq-5-spotted-charg...
> As a back of the envelope calculation, if you covered the ~2.44 m2 roof of a VW ID3 with solar panels you'd probably see somewhere in the region of 244 kWh / year (based on typical UK solar panel generation per year - this would be more in a sunny place).
Only 244 kWh/year?!? You'd get the same amount of energy by plugging in to a basic 120V North American household plug every weeknight (you don't even need to charge on weekends!).
Or 30 minutes per weeknight by plugging in to a basic UK household plug.
Or you could just leave it plugged in to a household outlet overnight once per week.
You need to at least half, but most likely more, your estimate if you talk about cars that live in the cities.
For solar panels efficiency, two main things that matter are proper angle to the sun and amount of shade. Parking in the city, you cannot choose to align your panels with a sun. And you’ll be surrounded by tall structures (buildings, trees, etc) that will shade your car. You’ll get nowhere near close to an efficiency of a house rooftop solar.
Having worked on a solar car as a student project, solar panels on a car are at best a marketing gimmick. There's definitely not enough area on a car to power a car anyone wants to drive, even under ideal conditions at a reasonable duty cycle, and issues of shading are even worse for a car than a stationary panel. Also solar panels are fragile and encapsulating them so that they are robust enough to be on the exterior of a car costs substantial weight. Putting solar panels on the car is only slightly better than putting them on the road surface.
If the car is decent as a plug-in electric car, then it still may be worth getting. If the solar panels are sufficiently non-intrusive they may even be close to neutral in terms of the utility of the car, but they do not improve it.
Based on the comments here this tech is for people who:
- don't drive very much
- but drive enough to spend tens of thousands on a new car
- but can't put a charger at their residence
- but can park somewhere that isn't shaded by trees or buildings or clouds or snow
Still, as the overall market for electric cars grows that can add up to millions of people. There's also another larger group:
- People who don't choose car options based on a fully considered rational utilitarian evaluation of cost/benefit
Which brings you up to >90% of car buyers ;). I'd probably pay for it if it's <$4000, it's much more utilitarian than 24" alloy wheels at least.
It makes very little sense to be lugging solar panels around. It's just not worth it. Install them at home and charge. It might make sense if your vehicle is large and mostly stationary in remote locations where electricity is not available.
Anyway, I think this product is fake and scam.
This idea will never be practical but it also seems it won't die. 69 miles per week of charging. Assuming the car is sitting outdoors all week and the weather is not cloudy.
A Tesla can charge more than this in an hour.
I like the idea, even if it only replenishes a small range over a week. However this marketing site is too loaded with exaggerations (Sweden is central to Europe?) and feels like a giant ad, cryptocurrency-token-like pitch, trying to hype vaporware. Are they trying to IPO next week via a SPAC?
Anyways my fluff-meter is triggered. Would love to be reassured otherwise because I love the idea even if it's unlikely to live up to the hype they're presenting.
I think this has an undervalued benefit: if you run out of charge somehow, the trickle will let you limp to the charging station.
Like, EVs going fast take far more power than cars going slow due to wind resistance, so if you're travelling 5KM/hr then you'll take an order of magnitude less power. And if you do run out of power, you only need to get to the nearest wall plug or charger.
Obviously, cost makes this a very niche feature currently and generally you shouldn't run out of battery in most situations anyway. That said, this could be a good "better late than never" sort of thing on luxury cars.
The comparisons that they’re showing on their “Solar Integration” page is disingenuous at best. They state their cells have 20-22% efficiency, comparing them to much older silicon cells with 16% efficiency. The reality is modern affordable cells [1] have the same %22 efficiency that they have.
“The polymer coatings of our cells do not splinter” but I bet the cells themselves sure as hell do. Cracks are hard to spot and can render an entire series string of cells useless. Top side body panels I wouldn’t be so worried about, but the doors... really?
[1] https://us.sunpower.com/sites/default/files/sp-gen2-solar-ce...
I call BS.
Any solar cell mounted on a roof of a car is going to be much more expensive and less efficient than a cell that can be mounted on a roof of a house.
Want to put a solar cell? Why not put it on your house instead? You can put as much of the cell as you can without the downsides of having it on your car. It will work for you even when you have your car parked in a garage.
With inclined roof the cell is going to be much more efficient than a car roof cell that has to be level.
Has anyone thought about parking the car in shade or garages? Now you have to park in a sunny place for a small increase in efficiency.
Here in eastern/northern Europe, the maximum values are normally unattainable throughout the year (at least here in Europe).
And no, the solar on a car is not going to prevent you from having to charge it, you still need to charge it, just a little less so it will not eliminate you having to have some place to charge it and fiddling with cables and chargers.
A bit of backstory of the company:
Initially they were founded in 2016. The founders built their prototype by-hand and themselves, which I find very inspiring.
In 2019 they had to do a crowdfunding campaign to raise 50M EUR for research costs so that they can go to mass market production. They had ~13000 signups in that campaign. Before that, most investors wanted a too revenue-focussed investment, and the company wanted to build an affordable mass-market car. They also embrace the vision of car sharing as a more sustainable infrastructure for cities.
The CES live presentation (probably why they are popular now) from earlier this year:
https://www.youtube.com/watch?v=OhlHJ9FA7q0
Personally, I think this is the kind of vision a company like this needs. I mean, we probably can agree that it's first-gen and that it will have a few bugs and quirks, we all know that.
But if more companies research on solar and battery technologies, they hopefully will get more efficient so that a concept like this can solve more edge cases.
And remember, Tesla didn't build their first-gen cars either; they did it the same and reused parts from Continental, BMW and Lotus among others.
Amusingly, the 2011 Nissan Leaf actually had a solar panel on its roof. It would help charge its internal battery–not the main one, but the 12V auxiliary battery. Trying to actually power the car itself is generally infeasible with solar panels attached to the car.
For the poor efficiency of solar panels, seems like a big gimmick to try to differentiate and spend a ton of R&D on (solar body panels).
I'd find it more interesting if you could just plug it directly into a solar array.
Solar Freaking Roadways v2 :)
This is very idiotic, all calculations presented are inflated by a factor of 10x. There is no practical advantage to having solar panels on a car, except maybe to trickle charge the starter 12V battery (on EV or ICE vehicles).
First to get to market but certainly not the only player in the solar-powered self-charging production car space. There's enough of them that there's a Wikipedia page - https://en.m.wikipedia.org/wiki/Solar_car
I think a lot of people here are missing one of the benefits.
When you have an EV there are two potential issues with charge. One is actually charging the car to get more miles to drive, which a solar panel (of reasonable size/weight) isn't going to contribute enough to.
The other issue is not losing charge when parked for long periods of time if not plugged in. If you don't have home or work charging then a 10 mile per day ambient battery drain is going to contribute a lot to how often you need to charge the car.
I think having at least some charging would be a nice peace of mind if you are doing something like parking the car in an airport parking lot for a couple of weeks. As a bonus you could use that energy for things like running the fan to keep the cabin from becoming melting hot in direct sun.
Could one install unfoldable solar-surfaces, to increase the input are while parked? Its additional weight and motors after all. In theory though, a car could increase the surface it has to the max allowed volume area of the region?
In germany that would be 2.55 m * 12m - thats 30 m^2.
RVs also use solar panels as one of the main sources of energy. But I have learned to avoid those flexible solar panels (that Sonos is seemingly using as well) because they do not last a long time. They break usually long before 10 years are over. Also it should be noted that solar panels lose efficiency the hotter they get. Solar panels that are directly glued on the surface have no ventilation and thus get hot, lose efficiency and the heat also does not help to make them last longer. Of course, properly mounted panels you find on most RVs cause a bit more drag. There are military grade flexible solar panels available that don’t have most of the mentioned side effects but they are like 5x more expensive.
I would like to have outside solar blind that I can cover front glass with when parking. It would also alleviate heating of the interior somewhat.
But it either need to be flexible (and expensive and prone to damage) or mechanically complicated and bulky, so...no dice.
Not convinced by this car. But as a general idea a little free air conditioning when parked could be very handy for many. Trickle charging the battery probably extends the life of an electric car and prevents long term problems of neglect
When I went travelling a couple of years ago I was trying to figure out if you could travel 100% solar powered.
Turns out it’s kind of possible if you cover a huge van with solar panels and have them extend out to make a larger surface area. And, are very patient. (One day of driving, two days of charging, or whatever.)
This may be a stupid question but given that these cars literally absorb light... do they pose a danger on the roads in terms of visibility to other motorists?
Besides all of the other reasons this is a terrible product, it's name is also way too close to that of the defunct Toyota offshoot "Scion".
I'd buy one and turn it into an RV. That use case makes a ton of sense. Fully integrated solar to power your electrical appliances while stationary.
That looks awesome! Living with a family in a sunny urban area, and not driving a whole lot (typically 0-4mi per day), I think we could get pretty far with that kind of charge capacity and range. I also love that it seems to be a van but looks a little more rugged and utilitarian compared to the typical soft and cushy look of minivans here in the US.
Too bad it seems to be EU only.
Aptera has a much more viable implementation of solar charging, because the vehicle's vastly higher efficiency means each watt-hour collected goes farther.
They estimate a full day of sun can gather 40 miles, meaning even relatively darker climates might get 10 miles per day.
Tesla Cybertruck may have an option for solar panels as a pickup bed cover, able to produce a few miles of range daily. Not much per dollar normally, but great that in a worst case scenario it can, given some time, harvest enough power to find an outlet.
Kind of neat, but I suspect the coating over those flexible cells will degrade like any other clearcoat and eventually cause significant efficiency loss. Especially when drivers are encouraged to just park it out in the sun.
I saw a pretty interesting van/RV project which actually had sizable amount of solar panels. About 8kW worth. They unfold and can be manually tilted and tracked to follow the sun roughly in the sky.
It’s pretty interesting. That much solar (with 140kWh of battery!) is more than sufficient to allow totally off-grid living and trips to the store. Now THAT would be interesting, if you could get the bugs worked out and mass produce it cheaply.
(It’s really hard to find affordable flexible solar panels. Regular solar panels weigh 3 times as much for the same power but cost a third as much in wholesale. Anyway know of cheap flexible solar panels, ie 50¢/Watt or so?)
Link to the solar van/RV: https://youtu.be/5uUh23GDW08
Isn't there already a car brand called Scion? Sion is too close.
i think people are underestimating how much energy is required for transportation and how little energy solar panels generate (relatively speaking). A Tesla is about 60 kWh on the low side for 300ish miles. The average American uses 30 kWh for house consumption. Let's say this car is super small, has a super efficient battery pack, and a logic defying solar panel, this car itself CAN SINGLE HANDED power your house. Forget about making cars. I want this shit on my house with these numbers.
It's not really practical as the main energy source, but a small solar panel would be good to keep the battery charged in cases where the car is parked for long periods.
Lightyear One is developing a solar car. https://lightyear.one
Their designer got to much inspiration from Tesla website, or I’m the only one who see’s that? ;-)
Why don't the cars simply get their power from the solar-freaking-roadways?
Do they have a working vehicle, or is this all renders?
Next up: really bright garage lights.
Is there scope for collection IR and UV from the windows?
Also can the chassis be made of batteries?
> [...] Sono Motors is providing a warranty for the Sion of probably two years or 100,000 kilometers [...]