Electric car that charges itself
sonomotors.com
sonomotors.com
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.
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:)
topping up 5 miles a day means that a full battery will last me and the 1.8 million UK cars that do under 2000 miles a year, months between having to plug in and recharge.
- For me, 5 miles a day would keep the battery topped off and I wouldn't have to visit a charger except on longer trips.
- Would also be much more palatable to limit the full-charge voltage to something a little lower, prolonging the battery's useful life, knowing it'll passively recharge daily.
- Would also enable more connected vehicle features.
- Given a choice between a car that slowly loses a bit of charge daily, or one that gains charge, everyone would pick one that gains.
- Would also lessen the fear of running out of charge a mile away from a charger and needing a tow truck, just wait a few hours if it's sunny, or at least charge enough to park somewhere safe and phone a friend to pick you up and leave it for a day.
- Could go on camping trips a bit further away and let it charge for a week, or use the AC/heater occasionally.
- If the car is covered in snow it can warm up the panels and melt some snow. Teslas can already do this but it's even more practical with PV on the roof.
As long as people understand this doesn't mean they can drive nonstop in the sun or that they'll get any significant short-term range boost, it's still extremely sensible.
I suspect most people would choose the one which is $2000 less and looks nicer.
> Could go on camping trips a bit further away and let it charge for a week, or use the AC/heater occasionally.
Totally agree here, but I’m not buying a car based on what I do a half dozen weekends a year either. More important is to ensure you have bigger battery capacity. Buying the Model Y Long range, I paid $8k 80 miles more range. That’s going to be far more useful than the 5 miles per day you might get out of this.
This is all around something I might pay for as an upgrade, but certainly not an important part of the purchase decision.
Yes, those are all useful things but you have to (as a manufacturer, at least) weigh them against all the costs of building this feature, making production more complex, deal with the returns/breakages, etc. etc. So like the parent comment said, the consensus seems to be "just not worth it".
even a small ammount of self charging would go a very long way to make the car more pleasent to use.
Definitely.
> That's a 10 minute bike ride tops.
Perhaps, though it may not be possible cover that 2 mile commute by bike and survive.
At one point I was staying in a hotel along a small highway in Texas and saw a strip mall with restaurants on the other side. After about twenty minutes trying to find a way across I gave up and got in my car to cross the road.
Transit policy in many US cities and towns is somewhere between indifferent and actively hostile to anyone who is not driving a car.
In general, it’s a good idea to park your car under cover for a lot of reasons. Fabrics don’t do well when exposed to the high heat you get parking in the sun for prolonged periods. If you live or work in a city, chances are high that you are parking in a covered garage or basement.
Solar roofs on cars are a neat idea, but not likely near as useful for most people as spending the money on more batteries for longer range.
The best way to spend money improving an EV is almost always going to be on batteries or weight reduction. Self charging is neat, but unless you get much more efficient solar arrays, it’s always going to be limited to niche applications. Five miles more range is always going to be useful, solar arrays which add a mile or two of range under specific conditions are far less interesting.
My main point though, is that the amount of electricity you can collect from the surface area of a car is very negligible. It's a very ambitious goal indeed. It's not worthless, it's basically free energy so anything gained is good I guess. It just seems there are a lot of people here that seem to think this is going to be better than it actually is. It's easy to get hyped up by the marketing, but my suspicion is it is much worse that we would wish.
I'm very skeptical of the numbers they have posted. Especially in England where hours of sunlight per year is below average. A quick search suggests England on average get roughly 1500 hours of sunshine per year. Comparatively, my state of South Carolina get upwards of 2800 hours. You should be looking at the 'cloudy' bars on the chart (https://sonomotors.com/en/solar-integration/). Assuming the charts are right, that's 77 Km per week at peak summer, and as low as 21 KM per week in the winter, realistically. If the weather of favorable, and you don't park in shade, then sure you could get better results.
We have basically reached the limit of what we can extract from solar cells, and there is not enough surface area on a small car to make 'the dream' come true, of having the car charge itself without plugging in.
It looks great on the marketing campaigns though. And I'll give this company credit, their body panel system does look very innovative. It seems they have made some important enhancements in this type of solar tech. And all things considered, the more electric cars on the road the better, I hope they sell a ton of them!
And in fact, for my short commute and I'm sure at least a few others, it would mean never having to visit a charger except for long trips.
Still - I have an EV that's sitting idle most of the time because of the pandemic. I had to plug it in a handful of times this year, that would mean plugging it in zero times.
Also, if it is very sunny, it means the car is hot. One common thing to do is to start climate control before getting into the car so it will be at a comfortable temperature. We would get this heat rejection for free?
Is it worth it? Not sure. Maybe. Everything else being the same (including price) I would pick a car equipped like this versus another car without this feature.
By the way, some Nissan Leaf trims had a small solar panel to charge the 12v battery. That was useful. Mine has to periodically connect the traction battery to do the same.
My main POV that I rambled around I guess, is I’m trying to temper expectations. Browsing through this thread, I’m just seeing too many folks who are expecting way too much out of this technology. I’m almost certain it will not deliver on the high hopes most people have for it. Even if that hope is you don’t have to charge on your very short commute.
It’s easy to get hyped up reading the marketing material on this company’s website. The idea seems great to the lay person. But the fact of the matter is when I hear Elon Musk say publicly that he and his team looked into it, & they determined it’s not an idea worth pursuing, I believe him.
Engineers & physicists way smarter than you and me have done the calculations. There is only so much energy you can get out tiny solar panels on a car body. Period. We’re talking about the laws of physics here. Conceptually it sounds amazing, in reality the result is lackluster.
Everyone wants to look at it with ‘best case scenario’ mentality, but day to day it’s just not going to be that effective. Again, not saying it’s nothing. There are some benefits.
But the added complexity of manufacturing? Could it be scaled larger than the 13K preorders they have? What happens when the panels start failing and need to be repaired? What happens when you get in a fender bender and half your ’solar grid’ goes offline, will you be willing or able to pay a specialist to repair the intricate solar grid in your car body?
It’s just a lot of effort and resources that could be focused elsewhere. Everyone is so excited because the concept sounds amazing, but the downsides & complexity are real. I seriously doubt this will power your car even for small commutes.
Cost is the reason. You have to consider cost.
You seem to be claiming it's better to travel 50 miles a day by car than 10 miles a day, which is clearly wrong.
I don’t understand at all how you interpret what I said to mean this.
If you want more kilometers per day from the solar panel, it makes sense to optimize the car. More streamlining, lightweight composites, narrower tyres, wheel fairings, smaller battery etc. For example https://en.wikipedia.org/wiki/Lightyear_One
That might change in future and sooner than we realize, especially when current trend is about self-sustainability. Switching all cars to run on electricity does not mean, that in future there will suddenly be more electricity(that will mainly be green), than we have now, so owners of current Teslas in future might be slapped with extra tax, because they are not self-charging. Future Teslas might have solar panels installed, but hardly that will be concern of Elon Musk, as his main income is not related to Tesla Inc, where he now owns only 18% shares and he earns more from space by ripping off NASA.
Your understanding is incorrect.
Perhaps there should be legal escape hatches from HOA rules specifically for energy efficiency upgrades. I don't generally advocate for centralization of power (ie, a state imposing its will on a community), but in the case of climate change I'll happily make exceptions.
For example, the FCC has a carve-out that allows you to put up a satellite dish, in spite of any HOA regulation.
It's not your property. Stay out.
To my neighbors who don't like solar panels because they "decrease property values" (the favorite bugaboo of HOAs), I reply that in 10 years any house that does not have solar panels will be perceived as deficient, especially in the southwestern US.
That is the time when a car parked in the hot sun causes the internal A/C to run to keep the car cooler.
Telsa cars will run the A/C when the internal temperatures reach 105°F (configurable)
This might be a good time to counterbalance the battery loss with the solar power peak.
I guess what I’m saying is, even if you had a solar trailer, you would lose a lot of the load flexibility of using a semi truck. And you wouldn’t want to plan a load where you needed the solar power. So either way, you’re planning for charging at fixed intervals. Solar might help a little here, but not very much.
You'd need some sort of standard for the trailer to provide electricity to a hybrid/electric truck but ignoring that (major) issue it seems like a pretty great idea.
It still doesn't work.
Delivery trucks make a little more sense, but they still have the problem of being in motion for a large chunk of the day. Basically you're just slightly increasing your watt mileage/range on sunny days.
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.
Cost, however, isn’t. The cells themselves are extremely cheap compared with the cost of putting them on a rooftop (in the case of homes), and in this case replaces the use of paint on the bodywork.
Specifically, the cost of cells is now down to ~$0.30/W, so 5 m^2 [0] of 200 W/m^2 would cost about $300. Similar arguments exist for PV roofing tiles being replacements for ceramic etc. tiles rather than the common sight of bulky window-size sheets attached after construction.
The claimed average range boost of 112 km/week (~3600 miles per year) in “average” conditions, and ~7900 miles per year in optimal conditions, definitely sounds about right to me based both on discussions last time a completely different PV consumer car was discussed here and on my BOTE calculations. Is that range worth $300 extra on the purchase price? Perhaps; it would pay for itself after ~1.88 years.
Doesn’t guarantee this isn’t vapourware (thinking of recent news about Nikola Corporation), but it is at least plausible.
[0] I am guesstimating the area
Also, what are "average" conditions? The website doesn't say. Stockholm or the Bay Area? This car will work much better in one of those places while in the other, PV panels on a car's roof are a gimmick. A relatively inexpensive and barely useful gimmick but still a gimmick.
Are you certain your panel costs are that low? Even NREL's estimates [1] put them much higher. Assuming that panel cost is roughly 30% of the US$ 2/W figure, that's still double what you're quoting and that's assuming cheap, mass-produced PV panels which the ones on this car most certainly are not.
I agree that buses and bus shelters are a good opportunity for solar, but this is a strange comparison.
First, if the panels really are as cheap as they claim (though I am skeptical) then wouldn't it make sense to do both? Why does it have to be either/or?
Second, I don't think anyone who is deciding whether to spring for the "solar" option on their electric car is weighing that against putting solar on their bus or bus shelter.
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.
At 1pm my south facing rooftop solar array is at 97% of peak output, and by 2pm it's down to 82% and falls off pretty sharply after that. At some point in the afternoon the shadow cast from across the street would block that direct sunlight.
According to their specs, the car goes 255km on a 35kWh pack which is ~7.286km/Wh. It says it can produce up to 245km of range which is roughly 33.6kWh a week or 4.8kWh a day at best. In my case, it would be closer to half that value at best (2.4kWh), we've been having overcast days and my array has been outputting half it's normal capacity (1.2kWh). That's over 60km of range which would probably work for me but is 1 day's commute for a lot of people.
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.
It's hard to imagine a scenario where I accidentally run out of batteries and then can afford to wait for MULTIPLE DAYS before finishing my trip. Pretty sure I'd at least want to get a tow to the nearest gas station, where they would be able to plug me in if necessary. Even a plain old 120V 15A plug has much more power than solar, and works overnight...
In a lot of places, it's either keep moving or hope someone finds you fast enough. Not all roads are within throwing distance of a town or city.
In more common cases, it might be enough to cover limited driving (I think it might be able to cover my current car utilization in full), or at least offload the grid a bit. And in remote locations with limited or no power, it'll give occasional driving capabilities.
That's not a small amount. The US DoT puts average US driving at around 13,500 miles/year. In Germany (Sono Motor's home market) it's 8,000.
So we're talking meeting nearly 7.5% of US, and 12.5% of German, average driving needs. Just from sticking a solar panel on the roof of a vehicle.
If a car in a real scenario get more than 3% of it's miles from these panels I would be surprised.
Still, it does seem like a useful feature. It should be plausible to run out of juice relatively close to an outlet (gas station, hotel, good samaritan, etc.) since electricity is virtually everywhere. Waiting a few hours to get to the nearest facility should not be too bad.
It's more of the capability that attracts me (like having insurance without ever needing).
Given typical numbers of panel output I wouldn't be surprised if it (nearly) pays for itself anyway, so I don't see the need to be overly skeptical. (ben_w estimates ~1.8 year payback)
See other arguments cited elsewhere as well: avoiding deep discharge in case of battery depletion. If you leave your depleted car sitting for a while (days? weeks?), you will see degradation of the precious battery, which represents most (about 40%) of the cost of the car. A cheap insurance to preserve your most vital asset is also a great feature.
If Starlink does remove the location restriction, I'll spend more time in the wilderness than I do at home.
It might not be practical to plug in a place you’re staying at.
This argument gets thrown around sometimes, but if you really consider it:
Who has time to wait a day or two at a random place, with no infrastructure? People who have no valueable job (where time is very valueable), and at the same time are outdoors enthusiasts who can sleep in a random spot? But who at the same time are in the market for a futuristic EV? Even for those, how many times out of each trip would that be a viable solution? If you consider this in practices, it just makes much more sense to call the tow truck.
And if you know that you are going on a really long trip where there is really no possibility to even call a tow truck (but like, where is that? Where is the place where you have a close proximity to an EV charger, otherwise you wouldn't be going there, and no possibility for a tow truck to access?), even in that unlikely circumstance - you can just already buy a 1000$ 10kg diesel generator and bring with you for emergencies.
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.
[1]https://electrek.co/2021/03/03/hyundai-ioniq-5-spotted-charg...
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.
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.
You seem to be aware that this is not the case but also not so much... can’t tell what your comment is trying to support.
The 2018 MOV winner (https://www.americansolarchallenge.org/the-competition/ameri... ) logged 1762 miles over 58.4 hours, or about 30mph average pace (with a 16.8kWh battery, but no external charging, just the ability to time-shift some energy).
That's with a vehicle that looks like this: https://www.youtube.com/watch?v=aE9gkYsR4TU
myself and lot of ppl i know would be very interested in a car that basically charges itself when used only a couple times a week for short trips.
not for the electricy cost but mainly for the convenience.
... in June IF YOU ARE REALLY REALLY LUCKY AND PARK IN FULL SUN. Full sun in June, no thanks. How much of that will be eaten up by the extra cooling necessary?
Also you might get away with having less/smaller/lighter batteries if you're able to generate more power yourself.
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.
I think they improve the car not just from a convenience perspective (i rarely drive more than 100 miles a week in the city) but also it helps more of your energy usage come from the sun rather than non-renewable sources you might be indirectly pulling from the wall.
You make it sound like you're using a lot of power in that bus, but an induction cook top is at most 2-3 KW. That is 4 horse power. If you want to crawl at 5 mph that might be enough (but not for a skoolie anyway).
Cars have a huge power-plant under the hood. 100kW per car, at least. All the cars in a city have far more power than the power plant that supplies the city. Think 10k cars (town)= 1 GW. That is a nuclear reactor...
All the cars in the US, 275 million vehicles, at an average of 100KW, have a combined power of 27.5 TW. The total installed electrical power plants in the US are around 0.5 TW. The whole world has only 6 TW of installed power plants.
Cars need a lot of power...
The Ami can charge off 13A 240V in 3 hours (6kW motor and 5.5kWh battery pack), and is useful for a number of duties eg. school runs, shopping, mobility, bad weather.
Obviously the car featured here isn't designed around light weight<->practical charging but I reckon you could make an ultralight design for 4/5 people. The other problem is other larger cars on the road, that's a separate debate from the technical one.
The idea, and especially with the car in the article here, is that your car can charge over the course of a few days.
The power for electric cars is delivered from the battery. The Chevy Bolt for example has a 60kwh battery. If you have 1kw of solar, it will take you 60 hours of sunlight to charge that battery assuming the efficiency of those cells is close to what they're rated for.
The car from the article has a 35kwh battery so around 35 hours of sunlight to fully charge on 1kw of solar. If I drive ~100 miles in the city every week, and the car from the article gets the claimed 200-220w/m2 of solar - It's definitely feasible to recoup your entire driving usage by it just basking in the sun when you aren't using it.
Earth receives 1kW of power from the sun, per square meter. A solar panel has an efficiency of 20%. So under ideal conditions, sun directly at 90%, no shades, you get 200W per sqm. Now, you have shades, less than 90% angles, dirt, etc. On average in the US, the capacity factor of solar PV farms is 25% (includes day/night changes). You will get less on your car, but let's say you do get 25% capacity factor. That leaves you with 1000 * 0.2 * 0.25 = 50W per square meter, 24/7. In a week that is 8400 Wh per square meter. To charge the 35kWh battery once a week, you need 35/8.4 ~ 4 square meters. 4 square meters is plausible. You could say that the car has more space for PVs, but you kind of have to mount them such that they have a decent angle, otherwise their efficiency drops 10 fold.
In the case of Chevy Bolt, if you have a 1kW of PV panels, used in ideal conditions, you would need 1kW * 0.25 * 240h = 60kW. 10 days to fully charge the 60kWh battery. If you manage to install 1kW (4-5 square meters) of panels on a volt at ideal conditions (tilted 30-35%), then you could drive it 200 miles every 10 days.
On the other hand, if you only drive 20 miles a day, you could recharge at a power outlet and 60kWh would cost you 6 dollars. 6 dollars per 10 days, that means fuel cost would be $219 a year. That is $3200 for 15 years. Is it really worth installing a heavy and complex system on the car if you can achieve the same and better results by just laying the panels on the ground, next to the carport?
I am all for integrating solar PV in a lot more things, like house sidings and windows, but putting it on cars is just a PR move.
A typical electric car averages 4 miles per kWh. At a speed of 40 miles an hour that's an average power of 10kW - 10% of that 100kW peak power output.
As for the car, I imagine people will burn the energy and more by turning on the air conditioning when they get into their hot car that they intentionally parked in the sun.
Did you glue(/etc) the panels to the roof or did you have to mount them on standoffs?
I remember seeing my first solar panel leaning against an old blue and white school bus at a music festival somewhere on the west coast, decades ago. They had a bunch of old auto batteries for storage.
You could cool it a bit with a Stirling engine and get a little more power from the overheated interior. ;-)
However, they do degrade noticeably over the space of even a couple years.
I agree with this.
The net grid draw of EVs would decrease if every EV were equipped with solar panels. It's a way of turning the footprint of the car into a source of energy. Not sure how the manufacturing costs work out, but you don't have to replace 100% of the plug-in aspect to substantially reduce the energy costs.
They weigh no more than two kg per square meter including some environmental protection.
- 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.
- Annual driving distance of petrol vehicles is 10000 km/year or less (250 km or ~155 miles per work week) [source: ACEA_Report_Vehicles_in_use-Europe_2017]. Extending this range by 112 km/week on average is not a bad proposition, if it's real.
- Average TCO in the first 5 years is over EUR 40_000 anyway [source: www.leaseplan.com/corporate/news-and-media/newsroom/2020/30-09-2020]. So most people who can afford a new car, can afford this one.
- The price tag EUR 25_500 is fair. VW Golf 8 is a vehicle of a similar size, and it starts at EUR 26_100, so it's basically the same.
- In the cities, street parking is often the only option, and most industrial areas use open parking; so getting some sunlight is not impossible.
So this tech is not more expensive than conventional vehicles (at least on paper). It can potentially reduce charging needs by 40% or more for a typical European user (who admittedly doesn't drive much). It's not very attractive without a network of easily accessible charging stations, but that applies to all EVs.
As you point out, by the standards of 'car accessories and upgrades', this one is probably reasonable and novel.
Looking at the chart they provide, that assumes perfect conditions in the month of June only. A sunny week in December will only provide 70km.
But going off the stated ‘average’ of 69.6 miles a week, roughly 10 miles for a whole day of collecting sun. You might get nice returns on a sunny day in the summer, but in general year round, your probably lucky to get 3-5 miles.
Elon Musk spoke about this on Joe Rogan recently, and said it’s just not worth it. The return on investment is just so small, and we’ve essentially reached the technical limits of what solar panels can provide. So we will likely never see this in a Tesla.
Tesla cars are heavier, twice as powerful and twice as expensive. Solar panels trade trade design freedom for utility. I'm not sure that big flat surfaces and an MPV silhouette would do well for a luxury vehicle.
In shopping mall parking lots there is often some chargers, but more often than not they seem to be occupied. With a car like this, unless you drive a lot, you can park the car anywhere in the parking lot and not think about the charger.
My pre-COVID commute was about 28 km if I chose the scenic route with no traffic lights, or 12 if I crossed the city (I usually took mass transit, so I could read instead of drive). My post-COVID commute will probably be much smaller, as we are all going remote with sporadic visits to the office. I can get to the beach or the mountains within 5 km. For my post-COVID needs, this car would almost never need to be plugged (maybe during winter because these latitudes make the days short).
Anyway, I think this product is fake and scam.
How much sunlight do they get in parking garages?
Obvious downsides include significant increases in repair costs in the event of an accident etc. But, panels have gotten cheap enough that this is at least worth considering.
PS: I agree it’s unlikely to turn into an actual product, but it’s at least theoretically possible.
Indeed.
I feel it is now like 1 in 3 EV projects as of late is a pure scam driven by stratospheric Tesla valuation.
Anything other than stratospheric sales from first year means they end up being dinner for existing manufacturers in low to mid-end.
And if they don't beat Tesla in the high-end, means they are dinner for Tesla.
Not to say a lion share of money still goes to people with zero automotive experience, or just above that of golf cart makers.
Far better to pick the thing you actually add and do just that. For these people, maybe it's the nicely conformal panel.
It's not a fake if its still in development, which it clearly is
About the fake, their car has suspiciously the same proportions than the BMW i3 and they have been accused of using many parts of an i3 in the past. But I want to believe they are trying for real. The i3 has a carbon fiber roof by the way.
This will only work in single-family homes. Where I live it's more common to have 4-floor buildings and street parking. In that case, the street gets enough sunlight for the car to charge enough for short-ish commutes (which are the norm for urbanites anyway).
> Anyway, I think this product is fake and scam.
I agree they are promising a lot, but they are not promising anything impossible. It's too soon to tell anyway and whoever invests in them must understand this is a high-risk/high-reward strategy.
A Tesla can charge more than this in an hour.
Solar charging ensures you only rarely have to plug it in to top it up, which is convenient. It also means that if you leave it sitting outside for long periods of time, it will be topped up rather than slightly drained when you get back to it. That convenience is not worth a lot of course but solar panels are cheap. And also, not having to pay for the electricity is nice.
E.g. my mother has a car that averages less than 3000 km/year (seriously). With this, she'd never have to plug it in (or rather visit a petrol station). My parents live in a small village and most of the trips are basically 15km round trips to a near by city. Something like this but a bit cheaper would be perfect for them and decimate their fuel expenses.
Will this cover all your needs? No of course not. But solar panels are cheap so the added cost of this convenience might be worth it.
No weight or vibration requirements, can use the electricity for your house too.
The only downside is you need to plug in.
Governments will likely be slow to implement on street charging. There is a market for something like this, if it works as well as they say - which I doubt.
[1] https://ec.europa.eu/eurostat/statistics-explained/index.php... [2] https://www.mortgagefinancegazette.com/market-news/housing/t...
Then you probably live in a city and would be better served by transport modes where you don't need a big upfront cost, and other expenses and hassle of owning your own vehicle. I mean bus, tram, metro rail, taxi, uber.
You can always qualify with further "what if you..." to find someone who matches this case. But by the time you're done it won't be a viable number of customers.
There is black-and white reasoning about this because the maths around "what is the surface area of the car, how much charge can it generate and how far can it go on that charge" is also black-and white. And not favourable.
As the other reply says, this is not "the debate of electric cars"; this is the debate about this specific electric car design, with the solar panels on the car.
It's not talking about the current argument. It's saying the current argument shares the property of arguing against the use-cases of people outside the target demographic.
People who argue "electric cars will never be viable" (and not anyone in this thread) commonly complain about lack of supercharging speed, despite that being a feature that most people (and all initial adopters) will only use once or twice a year, if ever. This will not be a problem for a long time, as right now only ~1% of car users have an EV and that won't be a major problem until we start running out of ICE car-owning EV buyers who don't need that, which is at least at the 50% mark.
This particular car is priced quite nicely even if it came without this. So does not sound like there is a lot of extra cost.
I'm guessing manufacturers spend more on things like seat warmers or other stuff manufacturers put in cars these days. Also these things are probably more likely to break.
And if you consider the environment, imagine the energy savings over the life time of the vehicle not charging from (potentially) dirty sources. It would only be a waste if that energy wasn't used which would require you to religiously plug it in the second you stop driving.
Also, panels can be recycled (just like cars and batteries) and mostly don't contain that much nasty stuff to begin with. So, I don't see the problem here necessarily.
I can imagine this seems absurdly low for suburban America.
Otherwise, 15 min trips become 60+ ones which makes everything impossible.
Perfect for people like my mother would be a self driving car that you can summon to your door in a few minutes. But even calling a taxi takes half an hour+. So it would have to be faster than that.
- bus: a few times a week (if at all), because of cost efficiency
- taxi: hours, + only if you book at least a day in advance, because they’re just not sitting there waiting for a call, they’re busy towards where people are/go, which is, like, the other way.
Throw in no/unstable/limited power grid, and you double down on one of the use cases.
I can find half a dozen car sharing vehicles in a 400m radius from my house.
Wouldn't they be even better suited to a regular electric car, parked under a roof of solar panels? The simple flat solar roof will be cheaper to make, and be a larger useful surface. And easier to replace, will keep the weather off the car, reduces car weight, etc.
The unknowns at this point are: what are people willing to pay and how much additional weight will they tolerate? And, how light and cheap can these panels be made with the technology available now? And whatever these numbers are now, they may change as public opinion, the price of energy, and technology change. It may be too early for this to be a viable product, or maybe not. It's good to see someone is trying it at least.
Also: a solar carport might be technically easier to make, but it will require building permits and probably hiring an electrician and manual labor assembling the structure and so on. And some people don't own the land they park their car on, and many people drive to work and park their car in a lot that either doesn't have solar roofs over the cars or the ones that do use that power to cut down on the company's power bills.
"worth" here implies the third factor that you didn't explicitly mention: how much power you get off them. And "69 miles per week of charging" is pretty small, hardly worth it unless it's extremely cheap in vehicle cost and weight.
You're not wrong with the qualifiers "people using their cars once or twice a week to drive 10km to do groceries" and "some people don't own the land they park their car on" but each qualifier of the prospective customer greatly decreases the potential market size. Combined with a qualifier that they must be without good access to shared transport (so not in a big city, but not on their own land); then you might be looking at corner cases, not a viable market.
While the technology isn't there yet, it seems likely that this will eventually be the case.
3 million cars in the UK do less than 3000 miles a year, 1.8 million do less than 2000.
*I only drive because, with no footpath most of the way, it's dangerous to walk and I would not feel safe cycling (the road attracts many idiot drivers because there is almost zero chance of encountering police).
> 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.
The 4.3 is pretty optimistic, most cars are rated around 3 miles per kwh, but I digress. Optimistically it'd mean 1000 miles per year or 19 miles per week, or 2.7 miles per day.
I'd say firstly, this is already a niche category. The average car drives 30 miles a day, or more than 10x what this would charge under optimistic mileage.
Second, the extra weight would likely make this comparison even worse.
Third, not really cost-efficient, either, to install a complete solar system for every 2.5 metres. Much of the cost isn't in the panels but in the system around it.
Fourth, I doubt even the 69 mile a week category of people will still mostly have personal cars within 5-10 years. The flexible car rental market is taking off. In Amsterdam for example there's now about 100 thousand users of Sharenow alone, one of the multiple car rental providers, on a population of about 800 thousand people. Anyone who drives 69 miles a week or 10 miles a day, is typically better off renting. At a speed of 20 miles per hour you're looking at 30 minutes or 6 euros per day for your complete car usage costs, i.e. 180 a month. That's less than most cars (300-400 a month) cost in insurance, deprecation, taxes, fuel and parking in Europe. These companies are expanding sufficiently to allow most people in this low-usage group to do away with a personal car within 5 years I think. By the time these solarpanel cars could even start coming online, it's likely that most cars will have increased usage rates and that these solar panels won't even power a few percent of the mileage.
What matters is the lowest 25% percentile. Getting 25% of the market is enough.
New technology is always a crapshoot, some pay off, some don't; but without a long term view we would still be driving a horse and buggy.
It's not short sighted thinking: Most people who use this site can do basic arithmetic.
The solar radiance under AM1.5 (which approximates the surface of the earth at the latitude of Europe, the US, or China) is around 1000 kW/m^2. The very best multi-bandgap solar cells in the lab today are about 47% efficient at converting sunlight to electricity. The very best DC-DC converters have about 95% efficiency in practice.
That means upper bound on energy production is about 445 W/m^2. On a sunny day. At noon. In June. For a panel directly facing the sun. With no shade.
That means you need slightly more than 3 m^2 of sun-facing panels at noon to achieve just the charging rate of a basic 120V North American household plug (1.44 kW from a NEMA 5-15, to be precise).
That means you need well over 3 m^2 of body-conforming panel to achieve that rate at noon. And that's the best case given infinite money. And production at other times of the day will be lower (even if you assume the car is parked in the middle of a flat desert).
Since the sun moves throughout the day, leaving such a car in the sun all day will only charge it about as much as charging from household plug for about 3-5 hours. Showing that is left as an exercise to the reader.
Industry experts thought the iPhone was a gimmick.
I still remember "No wireless. Less space than a Nomad. Lame"
I’m pretty sure this car can be plugged in too. In fact it has bidirectional charging, so a parking lot of these things could (theoretically) be connected into a huge solar system charging all the cars
Panels must be positioned to face the sun, must be unobscured, must be in daylight during prime hours to make it worthwhile. Car roofs are often none of those things.
You want car parks turned into solar stations? Then mount them in the car park over the cars, angled at the sun permanently. Its a simple change, cheaper, and works many many times better. And gets crap off your car making it lighter and reducing drag.
Or the other alternative, the shipping of petroleum on huge trucks to millions of locations.
But yeah, I'd draw the line at solar panels on car roof tops too... the excess is too much.
What interest me in designs like this is, can it receive sufficient power to overcome battery maintenance in cold weather even while sitting
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.
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 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...
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.
Last year I had to leave my car unused for three months, after which both the 12V battery and the hybrid battery were completely discharged.
Had there been a solar panel on the roof this wouldn't be an issue.
Nowadays most of the cost of solar is installation, so I don't think such a panel would be very expensive.
The 860W panel on the Prius Plug-In is a €2000 option, so it's around twice the price of a rooftop installation, but they're using 34% efficient, monocrystalline cells, so most of the expense comes from that.
You're making a big assumption there - that the parking lot is open to the sky which many airport parking lots are not.
Usually there are many parking lots open to the sky, and they even cost less.
I don't know of any airport that has 100% covered/underground parking spaces.
Many people don't have a roof, or don't have permission to put solar on them.
Many people drive very little per day on average, for them in makes absolute sense to have a vehicle which will trickle charge directly from the sun and cover most (if not all) their driving.
This car obviously isn't for you if you have a suitable roof and driveway, and drive many miles at one time.
Stuff deteriorates in open sun and high temperature and this applies to batteries. If you are cash strappend and own an EV then the batteries are going to be your focus as keeping them alive for as long as possible is going to largely determine your cost of owning the car.
All people I know that can't put their car in a garage will try to find shade. And that's in Poland where sun is never directly above.
I purchased a car last year and have yet to put on 3,000 miles this year since I started working from home. (And I took a day trip with it).
I live in an apartment with a garage, but I use it for storage and don't mind parking my car outside. (I don't care about leaving my car in the sun and I live in a Southern state where it gets hot)
I'd consider buying something like this if it was a little more mature (Maybe in a future/cheaper Tesla model) simply because I love the idea of leaving my car out so it can stay charged.
We don't all think like you and your neighbors.
Cars are expensive to develop. If you want to offer an affordable car you must have a lot of potential customers.
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.
That's not the general complaint. Most people don't think it will ever pay off the cost of the panel/electronics/waste, let alone offer any tangible benefit. It's not the sort of think you can iterate on, the roof is just only so big and the car uses a certain amount of power, neither of which they can usefully change.
> 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.
Yeah, crowdfunding, where you go to find scientifically and financially "unsophisticated" investors. Solar roadways do really well with this crowd.
> Before that, most investors wanted a too revenue-focussed investment, and the company wanted to build an affordable mass-market car.
Well, yeah. If I give you money to make a product I want that product to be useful enough to sell for a profit.
They should put their time into developing the easy-conforming solar panels and let people put them in actually useful places. (And perhaps someone would have an efficient car and could stick the panel on it, but then they'd know how little power they were going to get and be happy with it, as opposed to your typical greenwashed consumer scammed into "helping" the environment.)
Basically they were mostly used to run the internal fans if the inside temp was higher than outside. I think the PHEV Prius was able to charge a separate battery with solar if AC wasn't needed.
It was a handy option, not essential, but a slight comfort on hot days.
I'd find it more interesting if you could just plug it directly into a solar array.
An example of something that doesn't work well. Saw a guy that installed a heat pump water heater in his off grid house. In heat pump only mode it drew 500W. Problem he had to work around was it on startup it would flip on it's resistive heaters for a couple of seconds. Which would crowbar his inverter. And if he disconnected them it would throw a fault. A slight design change would make it work seamlessly.
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).
Aptera and Lightyear both have earlier projected delivery dates so even if we are saying "stock consumer car, off the lot, no after market" they're still wrong
People who know better are like "no it's not" and people who don't will spread it and be told they're wrong.
Solar charging solves the fueling problem for commuters in sunny environments, the narrative is compelling enough, no need to so prominently lie.
Besides people already don't really trust these boutique car manufacturers with unproven safety track records. It's a terrible first impression
Production should have started in 2019, and they have accepted money in 2018. It's now 2021 and we're looking at 2023 delivery, with a significant price increase.
In the meantime, the specs aren't all that interesting anymore.
Say what you will about next gen EV cars like the three wheeled EM solo, but they're actually shipping and I've even seen two on the street so far.
Lightyear isn't even looking to be US street legal at release. I'm excited about all the cool stuff in the works but let's see it happen.
It'd be kinda ironic if traditional brands like Škoda or BMW get to these milestones with successful launches first. So much for the thesis of Innovators Dilemma
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.
In germany that would be 2.55 m * 12m - thats 30 m^2.
But it either need to be flexible (and expensive and prone to damage) or mechanically complicated and bulky, so...no dice.
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.)
The main issue is the extra cost of this worth the 16km (10miles) in range added per day. It produces $1/day in electricity, so it needs to cost less than $2.5k for it to be cheaper than electricity.
This is highly dependent on what you pay in electricity (system produces 33kw/week on average).
Maybe under ideal conditions, at a very high per KWh price (25c or more). The math would only work in a very sunny place with very expensive electricity (Hawaii, perhaps?)
Nevertheless very black materials can be stunningly dark https://en.wikipedia.org/wiki/Vantablack
A quick Google search [1] suggests that a (standard?) solar panel absorbs ~2/3s of the light, so it probably reflects enough to make out the car on the road. But the question actually becomes valid and important once we discover solar panel material that can absorb even more light (think Vantablack-like absorption).
Very good question!
[1]: https://news.rpi.edu/luwakkey/2507, search for "absorbs 67.4 percent" on the page
Too bad it seems to be EU only.
They estimate a full day of sun can gather 40 miles, meaning even relatively darker climates might get 10 miles per day.
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
I think I'm right in saying that they've got a much better plan to mass manufacture now
I was excited to see something that, for my commute and location, I would rarely need to plug in. Then I saw that for my €25k investment it will "probably" work for 2 years, that's a no.