Might be a noob question, but why can't EVs have solar panels on them directly so they can get charged just by moving around? Or why can't we have SVs(Solar Vehicles)? Why do we have to use solar panels on EV stations rather than just having them on the vehicles themselves?
> The solar energy you can collect is about 750W/sq meter.
> A car roof is about 5’x5’, and if we are generous and include a trunk and hood area, maybe you are getting 60 sqft?
We must think metric, every inch of the way!
Anyway, PVCs currently max out at about 300W / square metre - and that's in ideal conditions.
I believe theoretical maximum energy per square metre (when light actually arrives at the planet surface) is conveniently pretty close to 1000W, assuming you're in the right place, but maximum efficiency of contemporary panels is only about 30%.
Pure solar is indeed to much of a constraint, it make it more challenging than propelling humans over roads in an enclosure needs to be.
A big problem is sharing the road with conventional vehicles. Many could probably drive straight though it, a Tesla could probably drive straight though it.
If the car must be a strong metal container the choices quickly reduce to the things on the market right now.
I was just trying to use “familiar” units. I could have led with 1 HP per square yard, and then you’d totally have license to call me out!
And yeah, I was just talking about solar flux, there’s a whole lot of real world losses to consider but my point was that none of this matters, it’s orders of magnitude away from ICE engine output.
It was the fact you started using units the world knows - albeit misspelling metre - but in the next sentence, comparing that same dimension, you used an apostrophe to allude to a unit that only 5% of the planet uses.
I think it is quite interesting, because it also tries to be maximal efficient, which increases the "reach" that the panels provide.
Don't get me wrong, this is a enthusiast car, but I think the economics could actually work for a small city car.
Currently here in Europe, buying a electric car makes sense for home owners, which can charge their vehicle for cheap at home (especially if you PV). But a lot of people living in cities don't have a cheap charging spot. A car with solar panels, which gains a few percents of charge each day (instead of losing some), e.g. enough for the daily commute to work, may be interesting for such people.
I would love to see a ultra cheap take on this. Maybe an electric tuktuk like someone else suggested, with some solar panels slapped on it.
For example, if you had an electric golf cart with a solar roof, on a sunny day…
With two adults, a speed of 35 MPH, an LLM suggested a ratio of 10:1—that is, the power demands of the golf cart were 10x what the solar could deliver in real time. (LLM considered also aerodynamic drag, rolling resistance of golf cart tires…). When I suggest a speed of 25 MPH, the ratio came down to 5:1.
Regardless, assuming batteries to store energy on the cart, it suggests a 10 minute drive to your neighborhood grocery store would require the golf cart to sit in the parking lot for close to an hour before it will have caught the batteries back up to their charge before you left home. (And this is at the rather impatient 25 MPH drive.)
To get to a better ratio you would have to engineer like hell to start squeezing the numerator. Make it radically aerodynamic, low-rolling resistance tires (probably the lowest hanging fruit), cut the weight significantly…
I do love the idea of something like an electric rickshaw or tuk-tuk. Maybe not streamlined, but you could get much better rolling resistance with something like bicycle tires—and weight could be kept in check.
To make the math more complicated, you could theoretically have an unfoldable solar roof. Say you have cute, tiny one-person car with trunkspace for two bags of groceries, call that 1/9 the footprint of a "normal" car, and give it an expanding roof that can fill up a typical parking space. So you get to multiply the numbers by 9, which would mean a 10-minute drive to the neighborhood grocery store would require 60/9 roughly 7 minute charging? That's getting really close to useable, so we must have cheated a little too much with some of the "simple" math. Also probably the unfoldable solar panel ideal really just doesn't work for some reason that's extremely obvious to engineers.
I doubt that it will go mainstream, since you can only unfold it when the car is at rest. And it's permanently like having a loaded roof-rack for aerodynamics and weight. You'd always be asking - why not get put the panels on the roof of a house or other fixed structure? Easier and you can add even more of them.
You absolutely can .. but in order to be self sustaining vehicles need to look somewhat like the builds that appear in Australian multi day solar races - ultra lightweight, extreme streamlining, zero driver comfort, no extras like cargo space and automatic rear doors, etc.
> With 100% efficiency the area of the car is too small to produce enough electricity to drive.
is false - Australia has been racing solar powered cars for a good many years now, clearly they generate sufficient power to drive, just not especially fast, with any reserve energy, or at night, with any real comfort, etc.
Ok, so lets say we didn't want 100% of the energy to come from those "self-sustainable panels on the car", but rather N%, so we keep most everything as-is, except switching all the outside body/chassi panels for solar panels, how much N% could we recover from that? Could it change so someone goes from needing to charge once every 3 days to once every 2 weeks lets say? Together with re-generative breaking, maybe it could at least have some impact.
You're off by an order of magnitude. It's a few hundred watts; an EV is consuming 10s of kilowatts. (Ignore the watt-watt/hour sloppiness, pls.) To charge my car 60% would take about 2 months. Ambient needs (battery cooling) would eat up more than I'd get back. At best it extends idle sit time.
How can a question be "off"? :D I literally used N% as to avoid replies like this, but seems you managed anyways...
> To charge my car 60% would take about 2 months.
Depends heavily on where you park and where in the world you live, wouldn't it? I use my car maybe 2-3 hours per week, most of the time it's just standing outside in sunny Spain, would that change the calculation anything?
The amount of power that can be generated from the surface area of a car is pretty small compared to how much a car consumes. And the cost hasn't been low enough compared to the value of the electricity it could produce.
Maybe someday the price will get so low it will be a no-brainer.
> Maybe someday the price will get so low it will be a no-brainer.
The cost of solar panels is already low, that's why it's booming. This cost isn't the main constraint any more.
Panels on a vehicle have stronger requirements for low weight, and vibration tolerance than those on a fixed structure. They contribute to the complexity of the vehicle's power systems. They have to be designed with vehicle aerodynamics in mind.
And of course the limited surface area means that you do all of that, for a component that's it's barely able to keep the vehicles' aircon running. The physics of that will remain the same. Even of the total costs are low (and factors such as the vehicle weighing more are an unavoidable cost), the benefits are lower.
At any price point, including free solar panels, there are good arguments to put the panels on a fixed structure instead.
So maybe it will happen when we have run out of non-moving surfaces to put the panels on. i.e. don't hold your breath.
> Aptera has this planned but not sure if they ever reach market maturity.
Yes, Aptera does not have a shipping product, and if they ship the current design it might not have a large market for it. The have been promising delivery for a long time now, so it certainly looks a lot like vapourware.
Well but that would be a problem for keeping the car infinitely running with only solar power. But what about just passively charging it while idle? Cars sit idle most of the time.
you get too little energy vs the cost of integrating it. It gets worse considering as a driver you want to park your car in shade/garage/multistory parkings
My understanding is that when buying a car you are dealing with an oligopoly. You might think that you have a lot of options, but they all come from the same source. Furthermore, big money control not only car production, but oil too. If they allow the ceo of a car company to come with such a car, they loose billions in the oil industry. So they have no incentive to do that.
New options do appear on the market like the new toyota prius with solar panel, but if you look at it you will see that they didn't even try to maximize the solar panel size. Still it gets 2 km extra range in bad conditions. Triple that and you have 6 km, in real conditions. If you use your car every other day, you will never charge it, ever. If you get average or above sun, you can drive it daily and not charge it ever. A big problem if you sell oil.
The problem with green energy is that it is very democratic and hard to control. Nobody with big money is interested in that.
To understand who controls your life, see all the draconian measures taken against electric scooters: cheap, not poluting, democratic, don't need a lot of space and so on. Everyone with money said: we can't allow that. Write defamatory articles in the media they control, pass laws against it and so on.
> The problem with green energy is that it is very democratic and hard to control.
It's not that I totally disagree with this - there is some truth to it. But it has no bearing at all on the question "can I put the panels on the car instead?" Which has been debunked in this thread and elsewhere many, many times.
The counterargument to what you say is that Solar is in fact booming. It is coming - oil money can slow it, but not stop it. They have more success in some countries than others. It's not a coincidence that China, which course desires energy independence but doesn't have access to a lot of oil, is leading the way. Sorry USA, you're laggards now.
But solar + battery is on an exponential ramp-up and getting big now. Each shock like the current Hormoz idiocy makes the case for it even more to the rest of the world. It's coming, fast.
Just, it's not useful on car roofs. That's a poor choice of panel location.
Just an aside, but China is the 5th largest oil producer. They have a lot of oil. The problem is that they're the 2nd largest oil consumer, so are still importing. Their current course is sufficient to achieve energy independence.
It's kind of unfortunate they don't need to further decarbonize to achieve that independence. There are some other fields that aren't yet economically valid to decarbonize. If China had a non-economic reason to decarbonize jet fuel, steel, plastic etc they might drive enough volume to make them economic.
There was a production car planned called the Lightyear One [0], originating from a Dutch student team, but if I recall correctly it was quite difficult and expensive to manufacture.
> but if I recall correctly it was quite difficult and expensive to manufacture
More importantly, seems they stopped manufacture it because they made a new version, that was supposed to be available in 2025, but I don't think I've seen it anywhere.
> However, in January 2023 Lightyear announced that it was halting production of the 0 model, redirecting their efforts towards production of Lightyear 2; Atlas Technologies B.V., the subsidiary responsible for the manufacture of the Lightyear 0, would be allowed to go bankrupt. As of 2023, the replacement, Lightyear 2, is slated to be US$40,000 and available in both Europe and North America, and to start production in 2025.
A much better idea is to 20x the surface area of solar panels, get ones that aren't as weight sensitive (and therefor expensive), mount them on your house or garage roof instead, and charge the EV off that when it's parked adjacent. Maybe add a battery as buffer for when the car's not there.
And it in fact has been an option on some cars, but not a popular one. It has been described as "worthless"
He came up with a design where the panels can can unfolded for a larger surface area. But you can only do that when the car is at rest. And it's permanently like having a loaded roof-rack. Its's still less practical than mounting solar panels on the roof of a house or other fixed structure.
Interesting. Currently building something simpler with outbound[1]. Decided to go with gRPC instead, but mine is mostly focusing on developers, for basic HTTP service reverse tunneling.
I’m working on a small deployment tool called push2start[1].
The goal is to make Docker Compose apps easier to deploy from a laptop to a remote server without a lot of custom scripts.
Right now, I’m trying to keep Compose as the source of truth and avoid creating another mini orchestrator.
You point it at a compose file, it transfers only the images that need to come from local, then deploys and gives status, logs, and restart controls from one CLI.
Nope! This is for development purposes only.
Say, for example, you have a frontend team that wants to connect to a service, and that service talks to other services to get a response, and you sort of want like a central point of connection for the frontend team just for development purposes only, not for production.
> every DERP server used by your tailnet must be accessible by every node on your tailnet at all times, otherwise you get hard-to-debug netsplits.
What would allow a given pair of nodes access a peer relay? Isn’t the peer relay by default also accessible by every node on the tailnet since it’s in the tailnet as well?
Remixify[1]. What I mean to
do is target DJs and people who love to own their playlist curating process. We aim to help people find remixes to their favourite Spotify playlists. Alt versions, club mixes, remixed versions, whatever. Come build your new experience.
Even if LLMs were trained on the answer, that doesn't mean they'll ever recommend it. Regardless of how accurate it may be. LLMs are black box next token predictors and that's part of the issue.
Complications and Being Mortal by Atul Gawande. Made me appreciate modern medicine more. One other l book that shifted my thinking completely about AI and how far we are from AGI: A Brief History Of Intelligence by Max Bennett. Evolution is a heck of an algorithm.
Also read Apple In China. Was pretty interesting to realize how much Apple (and China) are what they are because of how much they poured into each other
I'm building a utility to help DJs find "play-out" versions of tracks they already like[1]. You can play with it here[2]. Streaming services are optimized for Radio Edits. But to actually mix a track, I usually need the Extended Mix, Club Edit, or a specific Remix. Manually searching for the "DJ version" of every single track in a 50-song playlist is tedious administrative work that kills the joy of digging.
Remixify automates the search while leaving the selection to you. You paste a Spotify playlist URL, and it helps you or provides you a good starting point for digging. It groups the results by the original track so you can quickly preview and save the versions you want to a new playlist.
We don't try to recommend new music or use AI to guess your taste. It just finds the usable versions of the music you already selected.
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