Why no solar roof panel on Prius v?

The solar panel on the hatchback does nothing but power a vent fan to keep the interior cool.
It would take days for a small panel like that to provide enough juice to make any difference to the traction battery.

 

Beat me to it.

 

i have long wondered this. toyota is falling behind in another technology.

 

Falling behind whom?
Nobody's going to install solar panels to propel their car.

The vent fan implementation is actually a very nice touch.

 

they do a whole cross country race every year.

it won't be long before we'll have stick on solar cells that completely power the car. hang in there eric!

 

The cross country run car doesn't have to be crash tested. Or carry 5 passengers and enough luggage for a week. Or drive at night. It has to be escorted it is so slow and unsafe.

 

If you also look at some of the cross country cars, they are also designed to only carry one person, and slightly more aerodynamic in design that as an actual passenger type vehicle, it is practically impossible speed and structure wise on any viable street.

 

In addition to little benefit, there is an added weight consideration. The v wagon is larger, and heavier, by a few hundred pounds, than the hatchback. The solar roof would add even more weight to the v. The OP has already complained about the lack of acceleration capability of the v wagon in another thread. Adding weight would make it even more sluggish.

 

Not to mention what the solar panels would do to the aerodynamics of the v.

 

They don't seem to destroy the aerodynamics of my hatchback.

 

^ I would think zero, they'd be flush. But yeah, solar panels aren't that practical, for large app's.

 

Just for fun I decided to do some arithmetic. It's a bit crude, one of the engineers will probably shout at me...

How big could the roof panel be? Eyeballing it, 4 X 3 seems reasonableish. So 12 square feet. Cheapish panels can do 12 w/square foot but the efficiency of a car parked all higgely piggley is probably pretty terrible and the sun moves around so 6w?

So 8 hrs *6w/sq ft *12 sq ft = 576 wh. Obviously there's going to be some loss with the charging part. So if we drop 30% that leaves us with 400wh.

The battery is 1.3 kwh so if you parked at 30% you'd be at 60% when you left... ish.

 

Another thing being neglected to be considered here is the fact that most solar collecting cells are not super efficient at this time. Plus the fact that charging the battery doesn't really gain you much given how the Prius v is currently not a plug in hybrid, so you don't gain much benefit from having a fully charged battery as your current drive system is still going to go to gas when you start pushing your car above 50% power and/or traveling faster than 43 mph. The current Prius v engine, even with all the other Prius save the Prius Plugin, will always kick onto gas when you push your car past 50% power and/or exceed 43 mph. The Prius plugin, from what I recall, will only kick in after you push past 50-60 mph but only to a certain distance before the gas engine kicks in.

While the solar panel may help a little for the Prius plugin, again, the power demands of the Prius Plugin is much higher than what most solar panels that it would support will be practical.

And again, look at the size and also the design of the solar cross country vehicles. They are sporting MORE than the surface area to power the electric motor of the vehicle, must be lighter, and aerodynamic to sport that.

 

Now if they could develop micro solar cells that would be sprayed on with the paint over the whole car, that would open up new possibilities away from fossil fuel.