Model 3 may have Solar Roof that can charge the vehicle

[david_42]

I've been working with solar since 1979. Solar insolation in the USA averages 3.5 to 6 Kwhr/m2/day. Wafer-based cells peak at 22% for one-sun modules, so the best you could hope for is 1.3 Kwhr/m2/day and that's for collectors that are tracking in two-dimensions. Figure half that for non-tracking systems, like a car roof. With a 3 m2 roof, you'd be looking at 1.9 Kwhr/day.

For a realistic idea of what a fully solar-powered car looks like, go to the World Solar Challenge site. They are the absolute best we can do with our current technology and the race is run under ideal conditions.

 

[callmesam]

I've been working with solar since 1979. Solar insolation in the USA averages 3.5 to 6 Kwhr/m2/day. Wafer-based cells peak at 22% for one-sun modules, so the best you could hope for is 1.3 Kwhr/m2/day and that's for collectors that are tracking in two-dimensions. Figure half that for non-tracking systems, like a car roof. With a 3 m2 roof, you'd be looking at 1.9 Kwhr/day.

For a realistic idea of what a fully solar-powered car looks like, go to the World Solar Challenge site. They are the absolute best we can do with our current technology and the race is run under ideal conditions.

So an expected 8 miles per day for Model 3 if you assume ideal conditions? 2920 miles per year?

Even at 50% efficiency 1500 miles per year will be a drop in the bucket for the expected 30,000-50,000 miles a car might be a driven per year in the Tesla Network.

 

[callmesam]

But as a trickle charger? Sounds like an interesting use case. Especially as Tesla is driving cell prices below $.50/watt.

 

[bxr140]

So an expected 8 miles per day for Model 3 if you assume ideal conditions? 2920 miles per year?

Even at 50% efficiency 1500 miles per year will be a drop in the bucket for the expected 30,000-50,000 miles a car might be a driven per year in the Tesla Network.

Stop fake newsing your argument.

You've presented a complete falsehood in an effort to bolster your otherwise weak position. 30k miles/year, let alone 50k miles is by FAR the statistical exception. But if you disagree, feel free to "prove it" by fumbling through misrepresented data.

The average american drives 13,500/year. There are more cars on the road than licensed drivers (253M vs 214M, says the googles), which means the average car gets less than 13,500 miles per year. Tesla wants to become an average car; using average statistics is 100% valid.

Your 1500 miles/year solar car is a vehicle that could power 11% of its own annual mileage (using 13,500 miles/year). Even your ridiculous '30k average' car would power 5% of its annual mileage. Short of some emotionally irrational perspective, how are either of those numbers something to be furiously dismissed?

 

[callmesam]

Stop fake newsing your argument.

You've presented a complete falsehood in an effort to bolster your otherwise weak position. 30k miles/year, let alone 50k miles is by FAR the statistical exception. But if you disagree, feel free to "prove it" by fumbling through misrepresented data.

The average american drives 13,500/year. There are more cars on the road than licensed drivers (253M vs 214M, says the googles), which means the average car gets less than 13,500 miles per year. Tesla wants to become an average car; using average statistics is 100% valid.

Your 1500 miles/year solar car is a vehicle that could power 11% of its own annual mileage (using 13,500 miles/year). Even your ridiculous '30k average' car would power 5% of its annual mileage. Short of some emotionally irrational perspective, how are either of those numbers something to be furiously dismissed?

There's this new thing that Tesla is working on called the Tesla Network which would allow self driving cars to become like Uber or Lyft when you don't need to use your car. I'm sure we'll hear more about this in the new year.

The number of miles I selected was actually low for taxi service cars. It is my opinion that Tesla sees mobility as a service as the ultimate future of sustainable transport. That being said, I really like the idea of a deployable Solar cover or shield which would provide more mileage when the cars are static.

 

[callmesam]

Solar panels are measured in watts. Here's an article that talks about Tesla driving prices down to $.55 per watt.

$0.55 per watt from SolarCity's record-breaking new solar panel - ExtremeTech

Price per watt - Wikipedia

Aw @Topher don't remove your post which explains my comment.

 

[omgwtfbyobbq]

Totally agree and I can easily explain it as it's basic economics for those who don't believe....

Let's pretend you have a solar panel roof that generates 1 kWh per day (200W at 5 sun hours per day), every day. Let's say this roof costs you $1500.
Over the course of 20 years, 365 days a year, you've generated 7300 kWh of energy. The cost of residential energy averages 0.12 cents per kWh. This means that your solar panel roof after 20 years saved you from purchasing (7300*0.12) = $876 worth of electricity meaning you actually lost $624.

So, for what you might think was "free" still cost you $624 over someone who didn't buy a solar panel roof at all. Feel free to check the math and keep in mind these are ideal solar conditions for 20 years straight. Add in cloudy days and something called winter and it has just cost you more money. There is no complete return on investment during the life of the car.

A solar roof for your house is a much better deal than a solar panel roof for your car.

So lets pretend that Tesla, who just purchased Solar City, is charging $7.5/W for a +/-$1/W solar panel? Why stop there? Maybe they'll charge $3000? Why not $6000? Or better yet, $12,000! That's a terrible ROI! Totally illogical too!

I'm also skeptical of any consumer who's decision to purchase a solar panel on a car somehow prevents them from purchasing solar panels for their house. That's a false dilemma if I ever heard one.

False dilemma - Wikipedia

 

[omgwtfbyobbq]

Good point. It's arguable that a solar panel would actually be the asset that costs the least on the vehicle, once depreciation is considered.

Until the hypothetical Tesla ride sharing network launches, I can't think of anything that offsets costs (even if marginally) on a car. Am I missing one?

Just other car rental networks like Turo and so on.

 

[X-Auto]

So lets pretend that Tesla, who just purchased Solar City, is charging $7.5/W for a +/-$1/W solar panel? Why stop there? Maybe they'll charge $3000? Why not $6000? Or better yet, $12,000! That's a terrible ROI! Totally illogical too!

I'm also skeptical of any consumer who's decision to purchase a solar panel on a car somehow prevents them from purchasing solar panels for their house. That's a false dilemma if I ever heard one.

False dilemma - Wikipedia

Thanks for the link for "False Dilemma" for our low intellect !

 

[ohmman]

Just other car rental networks like Turo and so on.

Right. I was thinking more along the lines of vehicle options but I didn't state myself well.

 

[Garlan Garner]

My question is: who cares if there is a payback or not.

People order options on their car like pano roof and hi Def audio which have zero possibility of payback just because of the quality, aesthetics or personal preference.

Since when did convenience require a "payback?"

There isn't a requirement of payback. There are tons of suggestions that payback will occur.

 

[Garlan Garner]

Stop fake newsing your argument.

You've presented a complete falsehood in an effort to bolster your otherwise weak position. 30k miles/year, let alone 50k miles is by FAR the statistical exception. But if you disagree, feel free to "prove it" by fumbling through misrepresented data.

The average american drives 13,500/year. There are more cars on the road than licensed drivers (253M vs 214M, says the googles), which means the average car gets less than 13,500 miles per year. Tesla wants to become an average car; using average statistics is 100% valid.

Your 1500 miles/year solar car is a vehicle that could power 11% of its own annual mileage (using 13,500 miles/year). Even your ridiculous '30k average' car would power 5% of its annual mileage. Short of some emotionally irrational perspective, how are either of those numbers something to be furiously dismissed?

He did originally say TESLA NETWORK.......not Average Driver.

I cant believe the "funny" ratings of a post full of insults. It does not even matter who is right or wrong. WOW.

 

[callmesam]

He did originally say TESLA NETWORK.......not Average Driver.

I cant believe the "funny" ratings of a post full of insults. It does not even matter who is right or wrong. WOW.

He's wrong. It seemed kinder that a dislike and it's funny how spun-up people get when they don't understand something.

 

[callmesam]

There isn't a requirement of payback. There are tons of suggestions that payback will occur.

Payback will occur.
1. That payback will be slow.
2. That payback will be long.

How long is the payback on 21" wheels again?

 

[JeffK]

How long is the payback on 21" wheels again?

This comes when enough people who get the 21" wheels lobby local govt to fix the darn potholes!

 

[callmesam]

This comes when enough people who get the 21" wheels lobby local govt to fix the darn potholes!

Wait . . . The 21" wheels aren't a renewable resource?

At least the tires pay you back, right?

 

[Drone Flyer]

Not for at least 20 years!

 

[Troy]

I have done a little more research. It turns out the 2017 Toyota Prius PHV sold in Japan has a solar roof option as well. The video below is from Toyota's official Youtube channel.

125 Watts, Fisker Karma (source)
180 Watts, 2017 Toyota Prius PHV in Japan (source)
200 Watts, Karma Revero (source)
300 Watts, Ford Cmax (source)
300 Watts, Tesla Model 3 (my estimate)

If other car makers are offering this option, I don't see why Tesla shouldn't try it. Arguably, Tesla is the most suited company among all car makers to offer a solar car roof because they will soon start producing solar panels and solar tiles at Tesla's Buffalo plant. The solar car roofs would increase interest in Tesla's other solar products. Also, the glass solar car roof would look good next to glass solar roof tiles in Tesla stores.

The touchscreen in the car would display how much energy the solar roof generates. Similarly, there would be a website that shows how much energy the Tesla house roof generates. This is another feature that ties the two products together. It creates more talking points for tech reviewers and kids would love this feature too.

 

[shrspeedblade]

One has to consider that many options, when taken by themselves, would be considered an absurd waste of money later on (not that many absurdities occur in the aftermarket too!)

It's the fact that they are rolled into the much larger price of the car, combined with the convenience factor of it just coming as part of the package, that makes so many think, "Well, for only 8 dollars more per month....."

(And all of a sudden that pinstriping, woofer, trim, etc. is $500 bucks on a 60 month loan). That's the reality of modern car sales, and how much of the profit is made, in this day and age.

So I EASILY believe that if a solar roof is an option, they'll sell plenty if only for the simple fact that emotionally people will LOVE the concept of "the car making its own fuel while it's sitting there" for just 20 bucks a month more. If you plug every option into a calculator when buying a car you represent a DISTINCT MINORITY and truth be told you'll be selecting a solar roof/ obeche wood gloss interior/autopilot/stupid big wheels/color/ludicrous mode right along with the rest of us based on emotion and personal preferences despite what the calclulator says.

There, how's that? I just pointed out that a lot of argument over the last 10 pages has been about the wrong thing! Flame away!

 

[Carl]

A few pages back in this thread someone said current Model S owners were not worried about vampire charge. That's not exactly true. Imagine an ape-man going skiing (+/- 2014, when SuperChargers were less present, Destination Chargers did not exist, and it made no sense to travel 30km or so to find a 50km/hour slow charger - in some strange place potentially full of mammoths and smilodons - of course we have less of these situations now in the homo sapiens age of 2016, but still...).

Last Supercharger before ski resort is 130km or so away. Round trip is therefore doable if you "fill up" there, before letting your car sleep for a week, and charge there again one week later. But imagine the anxiety when you discover that in the freezing cold your vampire drain is more than 10km per day (note that I quickly discovered that one can reduce that to around 3 km/day by turning all connectivity off, but that's not my point here).

Trickle solar charge could really help in such situations.

Apart from that, I also think a trickle charging solar panel has a "feel good" effect which is not to be underestimated. A bit like free supercharging actually (it "costed" us 2000 euro in 2013, so I think my return on investment will be anywhere between 27 and 40 years, so it's obviously economical nonsense for me, but every time I'm supercharging I really, irrationally, like the idea that it's "free" for me now). Likewise, if after a four-hour meeting I see that my car's range is not down but actually up by a few km, thanks to a mini solar panel, I would probably like that, regardless of the math.