Solar PV on electric cars

[bdunham7]

At least we agree on our dislike of Prius's. But they are a convenient example to use so lets not get carried away.

The solar on the Prius Prime is actually only 180W. That is where the 3.7 mile/5.9 km comes from.
There was no way your estimated 0.6kW could fit on that roof, which is the only reason I suggested they might be using high efficiency cells. Edit: Misread by me.

And sorry, there is no way that the price is locked in at $2500 for only 180W using bog standard solar cells. Competition will fix that, and it will take time.

And the engineering point was about the solar roof failing the rollover test in the US. That part is clearly not sorted.

It is obvious it needs to be mass produced. The price will drop and then the collective power of all of the solar together becomes significant.

I don't dislike Prii per se, I just know the drivers.  I don't know where you got 0.6kW from, I had previously referred to 0.6kWh/day.  Everything else is just rough guesses.  But I have to ask--when you say significant, significant to whom and compared to what? 

[ahbushnell]

It is a big numbers game. Take 16 million cars and you have 4 to 6 km^2 worth of solar panels which are mass produced in a shape which fits their environment precisely, can be mounted using robots, don't need any extra space, don't need any infrastructure for connection and/or storage (storage is going to make solar and wind energy really expensive) and are right at the load.

don't need any infrastructure for connection and/or storage (storage is going to make solar and wind energy really expensive) and are right at the load.

The issue is it still needs both of those. And practically to the same extent as regular EV.

You have totally missed his point.

The point is, solar panels need storage and infrastructure (and management) if you put the solar panels _anywhere else_

Nope, you completely missed the point. Solar panels will barely charge battery existing in the car = provide only a small portion of energy needed. So you still need all of infrastructure regular EV needs.
Actually you could put 5 times smaller solar panel on a roof and most likely still get more energy from it in total. Given you use it as a normal car, not portable solar battery which you leave in rural empty space unobstructed by any buildings or trees.

Plus the weight of the panels and the associated power electronics will increase energy usage of the car. 

[bdunham7]

Well, everybody, I guess I was wrong.  Here you go....

https://lightyear.one/

[tautech]

Plus the weight of the panels and the associated power electronics will increase energy usage of the car.

Yep panels a little but the only electronics required is a charge pump, probably 50% of the size and weight of a car radio......nutthing.

Well, everybody, I guess I was wrong.  Here you go....

https://lightyear.one/

We're all wrong. hendorog alluded to this earlier when he mentioned the rate of change to these sorts of technologies and the possible efficiencies in price from mass production and improvements to PV's.

Do I see PV's on EV's as the bee's knees, NO, however if you're to have administrations subsidizing the adoption of EV's just to get to sell them make that subsidization a truly worthwhile investment of your nations taxpayers funds by saving some grid generation capacity while you're at it.

[wraper]

Well, everybody, I guess I was wrong.  Here you go....

https://lightyear.one/

Only $170k, what a steal!

[bdunham7]

Well, everybody, I guess I was wrong.  Here you go....

https://lightyear.one/

Only $170k, what a steal!

I think the 'steal' happens when you put your 120K euro deposit on vaporware...

[tautech]

Yeah well, it's only 75k NZ to just reserve a Roadster ! 
Full price: NZD$365,000     

Doesn't even come with a PV roof ! 

[wraper]

Yeah well, it's only 75k to just reserve a Roadster ! 
Full price: $365,000     

Doesn't even come with a PV roof ! 

First roadster more than a decade ago was cheaper than $170k. New one is expected to be almost 2x less than nonsense number you claim. Not to say you compare apples vs oranges, performance is simply incomparable. Fastest production car, with 1.9s 0-60 mph acceleration and 1000 km (620 mi) range on single charge (200 kWh battery). Why don't you compare it with say McLaren pricing? Also lighthyear one has only 60kWh battery. As big as cheapest Tesla model 3 has. There is one issue though, it has <$40k base price.

[Domagoj T]

If that lightyear one ever sells and achieves the claimed range from solar roof, I'll eat my porridge.
PVs on cars will always be sub-optimal solution. If you have a roof available, put the panels there, if you don't because you live in an urban environment, then your car will spend a lot of time in shadows anyway, so why bother?
That being said, solar bicycles and tricycles are viable, especially if they have an attached trailer. It simply boils down to much lower energy requirements.
https://solarbikeproject.com

[tautech]

Yeah well, it's only 75k to just reserve a Roadster ! 
Full price: $365,000     

Doesn't even come with a PV roof ! 

First roadster more than a decade ago was cheaper than $170k. New one is expected to be almost 2x less than nonsense number you claim.

Sorry, NZD. Will edit post.

[hendorog]

At least we agree on our dislike of Prius's. But they are a convenient example to use so lets not get carried away.

The solar on the Prius Prime is actually only 180W. That is where the 3.7 mile/5.9 km comes from.
There was no way your estimated 0.6kW could fit on that roof, which is the only reason I suggested they might be using high efficiency cells. Edit: Misread by me.

And sorry, there is no way that the price is locked in at $2500 for only 180W using bog standard solar cells. Competition will fix that, and it will take time.

And the engineering point was about the solar roof failing the rollover test in the US. That part is clearly not sorted.

It is obvious it needs to be mass produced. The price will drop and then the collective power of all of the solar together becomes significant.

I don't dislike Prii per se, I just know the drivers.  I don't know where you got 0.6kW from, I had previously referred to 0.6kWh/day.  Everything else is just rough guesses.  But I have to ask--when you say significant, significant to whom and compared to what?

Yes I read your comment too quickly and thought you had proposed 0.6kW as the panel capacity of the prius instead of the kWh generated by the panels per day. Took me a while to realise my mistake. My bad.

It has been well documented here that one small solar panel on an EV generates a rather insignificant amount of energy every day.

Now consider the number of EV's being produced per annum. Even the small amount of solar generation on each adds up to a significant total amount. That was what I meant by significant.

As to who would be interested, well that is above my pay grade, but logically I would think it would be of interest to governments and the electricity authority responsible for planning.

[nctnico]

If that lightyear one ever sells and achieves the claimed range from solar roof, I'll eat my porridge.

Ofcourse it achieves the claimed range from solar. It just take time to charge the battery while parked outside.  And the lightyear is extremely light and has optimised aerodynamics so it doesn't need as much energy as a regular car (be it EV or ICE). The improved aerodynamic shape isn't new at all and well known amongst hypermilers.

[wraper]

If that lightyear one ever sells and achieves the claimed range from solar roof, I'll eat my porridge.

Ofcourse it achieves the claimed range from solar. It just take time to charge the battery while parked outside.  And the lightyear is extremely light and has optimised aerodynamics so it doesn't need as much energy as a regular car (be it EV or ICE). The improved aerodynamic shape isn't new at all and well known amongst hypermilers.

Tesla model 3 is already most aerodynamic mass production car ever made.
EDIT: And sure it won't be light because it has substantial size battery.

[wraper]

Now consider the number of EV's being produced per annum. Even the small amount of solar generation on each adds up to a significant total amount. That was what I meant by significant.

I'll repeat it again. Multiplying bad doesn't not make it good. It's just waste of money and materials on large scale.
Here is analogy: If you make a lot of solar roadways, do they suddenly become a good thing?

[nctnico]

If that lightyear one ever sells and achieves the claimed range from solar roof, I'll eat my porridge.

Ofcourse it achieves the claimed range from solar. It just take time to charge the battery while parked outside.  And the lightyear is extremely light and has optimised aerodynamics so it doesn't need as much energy as a regular car (be it EV or ICE). The improved aerodynamic shape isn't new at all and well known amongst hypermilers.

Tesla model 3 is already most aerodynamic mass production car ever made.

Once they start producing the lightyear one not any more. Not by a long shot. Next time do more research before posting. Hint: the tail of the lightyear has a huge impact on the aerodynamics of a car because it minimizes drag.

[hendorog]

Now consider the number of EV's being produced per annum. Even the small amount of solar generation on each adds up to a significant total amount. That was what I meant by significant.

I'll repeat it again. Multiplying bad doesn't not make it good. It's just waste of money and materials on large scale.
Here is analogy: If you make a lot of solar roadways, dko they sudidenly become a good thing?

Your analagy sucks balls. The solar part in solar roadways falls to bits. The solar part on a car does not fall to bits.

Keep trying though. But please stop slapping yourself in the face. I didn't feel a thing.

[wraper]

Now consider the number of EV's being produced per annum. Even the small amount of solar generation on each adds up to a significant total amount. That was what I meant by significant.

I'll repeat it again. Multiplying bad doesn't not make it good. It's just waste of money and materials on large scale.
Here is analogy: If you make a lot of solar roadways, dko they sudidenly become a good thing?

Your analagy sucks balls. The solar part in solar roadways falls to bits. The solar part on a car does not fall to bits.

Keep trying though. But please stop slapping yourself in the face. I didn't feel a thing.

They are common in a way that both use solar panels in inefficient way. Not only reducing their efficiency but also vastly increasing cost of implementation. If Lightyear one gets even in a small crash, repair costs will be huge due to damaged parts including solar panels. Also you cant just paint it if some scratches appear. Not to say solar panel life will be limited to car life, so often you will be throwing them away prematurely.

[nctnico]

The failure in your reasoning is that efficiency doesn't matter. Only cost versus benefit does. A large part of a solar panel setup are cost for the space itself and installation costs. Putting solar panels on roads and / or on roofs of a car reduce the space and installation costs so the financial picture may be much more favourable even though the solar panels produce less electricity per surface area.

[wraper]

For the cost of Lightyear one you could buy Tesla model 3 and cover your house with solar panels and powerwalls from top to bottom.

[nctnico]

For the cost of Lightyear one you could buy Tesla model 3 and cover your house with solar panels and powerwalls from top to bottom.

Ofcourse because it is a novelty item. But if it catches on it will pave the way to have similar tails on other cars and make them way more efficient. You really should google 'hyper miling' and look at how people modify their cars to get significantly better mileage.

[wraper]

You really should google 'hyper miling' and look at how people modify their cars to get significantly better mileage.

That's not something any normal driver will ever do. You can hypermile on of the shelf tesla just fine as well. It's just trading off convenience for mileage.
https://www.teslarati.com/tesla-model-s-model-3-hypermile-world-records/

[NiHaoMike]

The failure in your reasoning is that efficiency doesn't matter. Only cost versus benefit does. A large part of a solar panel setup are cost for the space itself and installation costs. Putting solar panels on roads and / or on roofs of a car reduce the space and installation costs so the financial picture may be much more favourable even though the solar panels produce less electricity per surface area.

Put them on buildings instead, that's one of the best places to build solar. Get back to me once almost all usable roof area has been used for solar.

[nctnico]

The failure in your reasoning is that efficiency doesn't matter. Only cost versus benefit does. A large part of a solar panel setup are cost for the space itself and installation costs. Putting solar panels on roads and / or on roofs of a car reduce the space and installation costs so the financial picture may be much more favourable even though the solar panels produce less electricity per surface area.

Put them on buildings instead, that's one of the best places to build solar. Get back to me once almost all usable roof area has been used for solar.

Not true at all. Putting solar panels on my roof is a bad investment. I get a much better ROI if I install a dorm (roof extension) due to the extra space and therefore an increase of the value of my home.

[coppice]

The failure in your reasoning is that efficiency doesn't matter. Only cost versus benefit does. A large part of a solar panel setup are cost for the space itself and installation costs. Putting solar panels on roads and / or on roofs of a car reduce the space and installation costs so the financial picture may be much more favourable even though the solar panels produce less electricity per surface area.

Put them on buildings instead, that's one of the best places to build solar. Get back to me once almost all usable roof area has been used for solar.

Not true at all. Putting solar panels on my roof is a bad investment. I get a much better ROI if I install a dorm (roof extension) due to the extra space and thus increase in value of my home.

These two things are not mutually exclusive. The windows for the roof space rooms somewhat reduce the quantity of PV panels you can fit, but there are many many homes in the UK combining PV panels with roof space rooms.

[Marco]

Install costs of solar on cars will always be immense as long as they are 2D curved, there's just no way to do it cheaply.