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Electric car that charges itself

sonomotors.com

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Re: Electric car that charges itself

#311

Post by labcomputer »

onion2k wrote: post #31
onethought wrote: post #24

Earlier quoted context omitted.

True. Much better to just not generate any power so that they don’t charge themselves at all and don’t feed anything to the grid.

It'd be a more efficient use of money and resources to put the solar panels on a roof to generate more electricity than they'd generate on a car, and make a car with a bigger battery rather than solar panels. So yes, your sarcastic remark is actually 100% correct.

> It'd be a more efficient use of money and resources to put the solar panels on a roof to generate more electricity than they'd generate on a car

This is an under-appreciated point by the solar car advocates.

In order to get anywhere close to a practical self-charging car, you have to put panels on an area equivalent to covering the entire surface of the car (including the windows!).

For a conventionally-shaped car, approximately 1/3rd to 2/3rds of those panels (depending on the orientation of the car w.r.t. the sun) are producing essentially zero electricity. Either because they are actually facing away from the sun, or just at such an extreme angle to the sun.

In other words, you get between 50% to 200% more power by taking those panels off the car and slapping them on a roof. The difference in practice will be much greater in urban environments because buildings tend to shade the street (where cars park).

Re: Electric car that charges itself

#312

Post by dheera »

vidarh wrote: post #290
dheera wrote: post #277

Earlier quoted context omitted.

Honestly I don't see why we can't just outlaw HOAs. If you own something you should be able to do whatever you want with it. It seems like a simple constitutional right to me.

There is literally no place in the world where you can do "whatever you want" with property, for the simple reason that allowing you to do so would dramatically affect your neighbours in ways that would substantially restrict how they can use their property. It's a fair argument that conversely many types of restrictions on what you can do are unjustified and overly broad, but arguing from the basis that you should b…

> dramatically affect your neighbours in ways that would substantially restrict how they can use their property.

Well yes, if you practice the tuba at 3am, raise alligators in your backyard, and beekeeping in your front yard, then yes.

But painting your house? Building a shed? Parking a car in the driveway? Building a fence? Adding architectural ornaments? Install solar panels? None of this stuff affects neighbours.

Re: Electric car that charges itself

#313

Post by dwighttk »

leoedin wrote: post #106

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…

> If having solar panels on your car roof means you can avoid charging much in summer

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.

Re: Electric car that charges itself

#314

Post by puetzk »

agumonkey wrote: post #224
leoedin wrote: post #106

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…

And this is considering a car not made for this. A longer or van like model would have more surface. I often wonder if slow small buses wouldn't be possible on solar.

If you want to look at the limits of what physics seems to allow (cost practicality be damned), look at things like americansolarchallenge.org winners. They even have a multi-occupant-vehicle class nowadays.

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

Re: Electric car that charges itself

#315

Post by outworlder »

hnuser123456 wrote: post #307
40four wrote: post #301

Earlier quoted context omitted.

That's a good point. There are cars for the European market, and I don't think we'll be seeing many in the states. 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…

I really can't understand your POV. Of course it doesn't mean never having to visit a charger for cross-country trips, which is obviously a dream. It does mean the car adds charge passively rather than losing it, the panels are silly cheap compared to the cost of batteries, and the hardest part would just be integrating them into the body panels, which is certainly achievable. See my other comment in this thread wher…

It adds cost and complexity to the cars, so that's one reason not to do it.

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.

Re: Electric car that charges itself

#316

Post by outworlder »

crooked-v wrote: post #280
dheera wrote: post #277

Earlier quoted context omitted.

Honestly I don't see why we can't just outlaw HOAs. If you own something you should be able to do whatever you want with it. It seems like a simple constitutional right to me.

Eliminate HOAs and you've destroyed the basic mechanism that makes common maintenance practical for high-density non-rental housing.

HOAs are a US thing. Would you be surprised to know that high density housing exist elsewhere, with common areas, which are not maintained by HOAs?

Re: Electric car that charges itself

#317

Post by dheera »

jandrese wrote: post #288
dheera wrote: post #277

Earlier quoted context omitted.

Honestly I don't see why we can't just outlaw HOAs. If you own something you should be able to do whatever you want with it. It seems like a simple constitutional right to me.

HoAs are how neighborhoods fund communal property like pools, parks, plowing of parking lots, etc... Where you get into trouble is when they also try to enforce "property value" guidelines, which tend to become "against whatever the most power tripping person on the council thinks is 'ugly'". Solar panels are exactly the sort of thing that can be considered "ugly" and end up being banned. Beauty is in the eye of the…

> HoAs are how neighborhoods fund communal property like pools, parks, plowing of parking lots, etc...

All of that stuff can exist without HOAs. If you want access to communal property and a communal parking sticker, you can require a membership fee. As long as it's reasonably priced I'd most likely gladly pay for access to parks and communal facilities and stuff like that. It should be optional, but for the above, I'd be likely to opt in and I'm sure most people would.

But no, I would not pay for them to come and yak at me for how I should decorate my front yard and house.

Re: Electric car that charges itself

#318

Post by vkou »

outworlder wrote: post #316
crooked-v wrote: post #280

Earlier quoted context omitted.

Eliminate HOAs and you've destroyed the basic mechanism that makes common maintenance practical for high-density non-rental housing.

HOAs are a US thing. Would you be surprised to know that high density housing exist elsewhere, with common areas, which are not maintained by HOAs?

Yeah, it does exist in other places not maintained by HOAs.

It's maintained by an organization that is the exact same thing as an HOA, but is called a strata.

Re: Electric car that charges itself

#319

Post by ogre_codes »

iso1631 wrote: post #281
40four wrote: post #220

Earlier quoted context omitted.

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 yo…

Musk is building cars for a mainly american style market - long drives and private parking. 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.

If your commute is less than 5 miles a day, you should probably be riding a bike or an ebike. Pushing around a big car to travel what is essentially walking distance is a waste (and expensive). Even 10 miles a day is easy ebike range.

Re: Electric car that charges itself

#320

Post by scsilver »

leoedin wrote: post #106

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…

I see solar roofs all the time on camper vans out here, I think the combo of smart ev trailer for out west living is becoming such a value proposition. Especially if I can use leverage some of the car/trailer mounted solar for reducing my electric demands. I wonder when we will start seeing solar power plants/mobile home combos.
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