Poll: Solar car roof?

[dark cloud]

All this recent discussion around a refreshed or perhaps a Plaid Model S had me ponder the solar roof option. There has been discussion before, Tesla has considered it I'm sure, and the obvious conclusion was it was not worth the expense, or they preferred a sunroof instead, and then after sunroofs were optional, preferred a panoramic roof instead.

I recently discovered Hyundai has a solar roof on their sub-$30K Sonata Hybrid. Tesla's model S retails for over twice this. Both companies have a solar panel division therefore I think the cost of employing this "option" is comparable. Now honestly I have not been inside the Hyundai, and do not know what it looks like from the inside, but I assume it is a regular lined roof.

Of course the amount of energy retrieved from a small solar panel on the roof is pennies, but every little bit helps; range is king when it comes to electric vehicles. How many of you have had range anxiety and ran down to 5% battery travelling to a supercharger? I have.

Beyond the electrical/energy considerations I personally would consider this revision quite favourably; for me there would be a "cool" factor with a solar panel on the roof of my car, greater than any video game or Netflix. I'm not sure what possible revision with a refreshed model S would appeal to me more, a 120 kWh battery for sure, but that would bring at least another $5-7 k cost too. (Maybe more?) If I were in the market for a model S, and there was an option for a solar roof for $1000 I would definitely do it. And yes, Tesla would not offer roof choices, they prefer to keep things simple and have less options, but a vote for $1000 would imply interest that it is worth the additional price of manufacture.

Thought I would get others options/thoughts on this.

 

[BigNick]

All this recent discussion around a refreshed or perhaps a Plaid Model S had me ponder the solar roof option. There has been discussion before, Tesla has considered it I'm sure, and the obvious conclusion was it was not worth the expense, or they preferred a sunroof instead, and then after sunroofs were optional, preferred a panoramic roof instead.

I recently discovered Hyundai has a solar roof on their sub-$30K Sonata Hybrid. Tesla's model S retails for over twice this. Both companies have a solar panel division therefore I think the cost of employing this "option" is comparable. Now honestly I have not been inside the Hyundai, and do not know what it looks like from the inside, but I assume it is a regular lined roof.

Of course the amount of energy retrieved from a small solar panel on the roof is pennies, but every little bit helps; range is king when it comes to electric vehicles. How many of you have had range anxiety and ran down to 5% battery travelling to a supercharger? I have.

Beyond the electrical/energy considerations I personally would consider this revision quite favourably; for me there would be a "cool" factor with a solar panel on the roof of my car, greater than any video game or Netflix. I'm not sure what possible revision with a refreshed model S would appeal to me more, a 120 kWh battery for sure, but that would bring at least another $5-7 k cost too. (Maybe more?) If I were in the market for a model S, and there was an option for a solar roof for $1000 I would definitely do it. And yes, Tesla would not offer roof choices, they prefer to keep things simple and have less options, but a vote for $1000 would imply interest that it is worth the additional price of manufacture.

Thought I would get others options/thoughts on this.

Fisker had a solar roof about 10 years ago. I don’t recall if it was standard or an option.

They went bankrupt, but the Karma Revero that is being produced today is based on the same design. I don’t know if it still has a solar roof (optional or standard).

I would only want the solar roof if it didn’t make the roof glass opaque.

 

[COS Blue]

I think it could be useful if you don't have charging at your home, or if you are away from a charger for a while like on vacation. Even then, though, I don't think it would keep you from having to plug in. So probably marginal benefit... it would have cool-factor though.

 

[tstolze]

Just some very random numbers pulled from my head.
Thinking 1-3 kWh's per day on a sunny day with no shading. Our 8 year old 255 watt panels on our west facing roof produce .6 to 1.7 kWh's per day depending on the time of year.
Over the lifetime of the vehicle this would really add up, I'm not sure of the net cost, a custom designed roof with integrated solar and changes to the vehicles charging system or a separate charge controller.

 

[Stavanger]

Just some very random numbers pulled from my head.
Thinking 1-3 kWh's per day on a sunny day with no shading. Our 8 year old 255 watt panels on our west facing roof produce .6 to 1.7 kWh's per day depending on the time of year.
Over the lifetime of the vehicle this would really add up, I'm not sure of the net cost, a custom designed roof with integrated solar and changes to the vehicles charging system or a separate charge controller.

It would maybe possibly generate 1kwt per day if you always had it parked perfectly angled towards the sun with nothing shading it. In reality you will park at the wrong angle with probably some tree or house or something shading it.

in reality even if you always street park you will only be at optimal positioning a small % of the time so its more likely your avg will be 100 watts per day. Thats just 35kwh per year, 350kwh for 10 years, which atleast in my country would be worth about 35USD.

Parking in the sun outside is really terrible for your cars paint though so it should be avoided, 10 years of parking in the sun will be really bad for your paint and that will cost you a lot more then 35USD.

 

[46&2]

From an energy efficiency standpoint, a solar roof is stupid. The ressources used to produce a panel should be used as clever as possible, which means the new module has to go on a roof of a building, well angled towards the light. NOT on top of a car where it risks being in the shade more often than reasonable (and a house's roof).

My panels deliver 310 Wp each, about as big as a Model S roof. Minus the MCU and charging system power draw (100W? 150? more?) while not sleeping, charging... what's the net 'benefit'? That module is wasted. Put it on buildings.

I know other car manufacturers use it as an argument. A gimmick. White washing one's image...

 

[ucmndd]

Expensive gimmick. No thanks.

 

[LN1_Casey]

There isn't enough viable surface area on the model S. The Cybertruck has a lot more usable space, but even then it's a minimal amount of energy gained.

 

[BrokerDon]

Our 2012 Toyota Prius Four came with a sunroof over the front seats and solar over the rear. The ONLY thing it powered was a fan to intake fresh air to keep the cabin about the same temperature as the ambient air with all the windows and sunroof closed. Great on hot sunny days so the cabin didn't become an oven... but definitely very limited functionality.

 

[dark cloud]

It would maybe possibly generate 1kwt per day if you always had it parked perfectly angled towards the sun with nothing shading it. In reality you will park at the wrong angle with probably some tree or house or something shading it.

I see you are in Norway, so you are correct in the fact that Norway is at latitude of 60 degrees. Where I am at the sun is quite low in the sky, and I am at 50 degrees. Whereas California is at 37 degrees.

in reality even if you always street park you will only be at optimal positioning a small % of the time so its more likely your avg will be 100 watts per day. Thats just 35kwh per year, 350kwh for 10 years, which atleast in my country would be worth about 35USD.

In reality, this article stated that they actually received 1.24 kWh in 4 days, which prorates to 113 kWh per year. And this was in Portland in cloudy weather. Again, in your country maybe yours numbers are accurate, but in optimum conditions Hyundai states it produces 205 watts, which could easily be in excess of 1 kWh per day in sunny locations where a huge proportion of the Teslas are located. Some days it is in the garage and you get zero, and others it is outside for over 10 hours in the summer and 2 kWh is possible. Not you and probably not me, but I don't think it is too lofty for many owners closer to the equator to average 1kWh per day: 365 kWh per year in California is 350 x 0.18 = $66 per year.

Like I said, it is pennies, but if this was at no additional cost I would take the $66 per year.

 

[dark cloud]

Expensive gimmick. No thanks.

Is it expensive though? That panoramic roof sure isn't cheap.

 

[SO16]

Is it expensive though? That panoramic roof sure isn't cheap.

Expensive for very little gain.

The pano roof has much more “functionality”.

 

[ucmndd]

Is it expensive though? That panoramic roof sure isn't cheap.

I don’t want the pano roof either, but the solid glass panel on my roof is more than expensive enough to replace without them putting solar cells in it.

Again, it’s a stupid gimmick. Let’s assume a super optimistic case where you can get 300w from a solar roof in perfect conditions.

What does it take to keep the car’s computers and charging circuitry running to pump that into the battery? At least 150-200 watts?

There is no benefit. It’s a gimmick.

 

[Stavanger]

I see you are in Norway, so you are correct in the fact that Norway is at latitude of 60 degrees. Where I am at the sun is quite low in the sky, and I am at 50 degrees. Whereas California is at 37 degrees.



In reality, this article stated that they actually received 1.24 kWh in 4 days, which prorates to 113 kWh per year. And this was in Portland in cloudy weather. Again, in your country maybe yours numbers are accurate, but in optimum conditions Hyundai states it produces 205 watts, which could easily be in excess of 1 kWh per day in sunny locations where a huge proportion of the Teslas are located. Some days it is in the garage and you get zero, and others it is outside for over 10 hours in the summer and 2 kWh is possible. Not you and probably not me, but I don't think it is too lofty for many owners closer to the equator to average 1kWh per day: 365 kWh per year in California is 350 x 0.18 = $66 per year.

Like I said, it is pennies, but if this was at no additional cost I would take the $66 per year.

Actually the position of the sun varies wildly here.
During the summer if goes straight over the sky.
Now its vinter so the sun barely goes over the mountains. In fact a little further North here the sun never even rises in the winter.

Norway is extremly well suited for solar panels, in the winter it kinda sucks sure but in the summer the sun never really sets so you will generate power up to 24 hours a day in some locations here.

Im sure the panels could generate 205 watts, but again they wont, they will need to be angled perfectly towards the sun for that rate and the sun moves during the day no matter where you live. so unless you keep moving the car around to follow the sun you will not get that for all of the day. This is the reason why products like "solar tracker" has been invented.

 

[46&2]

Like I said, it is pennies, but if this was at no additional cost I would take the $66 per year.

Put that module on a building's roof, safe 66 per year, and sell the excess...

 

[bob_p]

Compared to the power stored in EV batteries, solar roof panels will never generate enough energy to have any impact.

For aerodynamics, the solar panels would have to be flexible, or built into the glass (like the Tesla solar roof).

Assuming the following:

• Tesla figured out how to get 400W of solar on the roof
• The vehicle is in the sun all day - for the equivalent of 6 hours of full sun
• The angle of the sun provides 75% efficiency for power generation

During a day in the sun, the solar roof panels would provide 1.8 KWh of energy - or about enough to drive 6 miles in an S or X.

And the above assumptions are likely pretty optimistic, so typical power generated would likely be much less.

While it sounds interesting to generate solar energy - the reality is that EVs use A LOT of power - and would require a large amount of solar panels to have any impact.

Now... If we could only get a Mr. Fusion (from the Back to the Future movies)...