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Electric car that charges itself

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Re: Electric car that charges itself

#261

Post by RandallBrown »

mbreese wrote: post #233
agumonkey wrote: post #226

Earlier quoted context omitted.

He didn't mention the semi ? The large flat area, long time under the sun, difference of market (no need to integrate it pretty, a simple flatbed on top would do)

Semi trucks and trailers are two different components. Most trailers have a large flat area, but these can get swapped often. And even within the same company you won’t always have the solar trailer hooked up to the electric semi. The swappable nature of the load is part of the appeal of semis. 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 tr…

Couldn't it make the cost of shipping cheaper if the the load is able to contribute some energy to the truck?

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.

Re: Electric car that charges itself

#263

Post by gigel82 »

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).

Re: Electric car that charges itself

#264

Post by mikestew »

stonemetal12 wrote: post #194
samcheng wrote: post #170

Earlier quoted context omitted.

I'm an electric car driver, and I'm still skeptical. 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...

The only plus I can see is that if you leave your car at the airport for a week or some other long term parking situation, you don't come back to a dead battery.

Over the past twelve months our Leaf has sat for weeks at a time without being driven. It has never failed to “start”. When it sits at the airport, it sits in the charger spot with all the other EVS.

Re: Electric car that charges itself

#265

Post by mavhc »

slfnflctd wrote: post #157
mavhc wrote: post #110

Earlier quoted context omitted.

Why hasn't the owner of the house put solar panels up? They own a house, by definition they're into long term investing

My HOA doesn't allow it or I'd have them already. And there is no way to fix this because the way the HOA is set up, it is impossible to get a quorum to change it.

Flood their houses to prove a point.

Re: Electric car that charges itself

#266

Post by justapassenger »

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…

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.

Re: Electric car that charges itself

#267

Post by rtkwe »

RandallBrown wrote: post #261
mbreese wrote: post #233

Earlier quoted context omitted.

Semi trucks and trailers are two different components. Most trailers have a large flat area, but these can get swapped often. And even within the same company you won’t always have the solar trailer hooked up to the electric semi. The swappable nature of the load is part of the appeal of semis. 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 tr…

Couldn't it make the cost of shipping cheaper if the the load is able to contribute some energy to the truck? 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.

But it makes the trailers significantly more expensive and the shipping cost more variable because the amount contributed by the trailer will be extremely variable. On top of that to cut down on cost you'd want the inverters to be on the tractor instead of the trailer but now you have truckers working around and having to plug and unplug live HV DC connectors as they connect and disconnect. Plus now the trailers are a hazard to worry about when they're just sitting around because there's all those solar cells creating big DC volatages just waiting for a circuit to be made.

Re: Electric car that charges itself

#268

Post by agumonkey »

mbreese wrote: post #233
agumonkey wrote: post #226

Earlier quoted context omitted.

He didn't mention the semi ? The large flat area, long time under the sun, difference of market (no need to integrate it pretty, a simple flatbed on top would do)

Semi trucks and trailers are two different components. Most trailers have a large flat area, but these can get swapped often. And even within the same company you won’t always have the solar trailer hooked up to the electric semi. The swappable nature of the load is part of the appeal of semis. 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 tr…

I see, unless there's an army of solar trailers it's not useful.

Re: Electric car that charges itself

#269

Post by rtkwe »

cptskippy wrote: post #240
dmos62 wrote: post #195

Earlier quoted context omitted.

Question is whether the panels on the car's roof or on the building's roof can be installed cheaper, and how the installation+maintainance / energy output ratio compares.

Don't discount the fact that a car may not have direct sunlight where it's parked, particularly a city car with high buildings surrounding it. I could park a solar panel in my driveway and it wouldn't receive direct sunlight until about 1pm. 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 shado…

Also I bet the efficiency numbers are for the panel receiving optimal direct sunlight not the high angle light it's going to get because it's on the side of a car nearly vertical.

Re: Electric car that charges itself

#270

Post by meragrin_ »

jiofih wrote: post #129
baybal2 wrote: post #122

Earlier quoted context omitted.

No, even if you make the half of car surface a solar panel, you would probably not even get a net benefit because of extra weight, and drag from suboptimal hull shape needed to place cells.

Did you look at the URL posted at all? The car is in final design stages, has enough cells to deliver 250km of range per week.

> Did you look at the URL posted at all? The car is in final design stages, has enough cells to deliver 250km of range per week.

... 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?

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