I recently attended a lecture on dynamic charging of EVs. Theoretically speaking slapping a solar panel on a car to charge it is feasible, but by putting on solar panels it will add a lot more additional weight and will result in larger wind resistance.
The car would ultimately use more if not the same energy (with the additional energy supplied by the solar panel) then if it didn’t have it in the first place.
Whoever gave that lecture is more than a decade behind the times then. Flexible solar panels exist, and technically the solar cells themselves are very lightweight. It’s generally the protective glass that sandwiches the cells that make up most of the weight.
And these cars already exist. BYD, Hyundai Ionic 5, Toyota Prius Prime, etc, are all production cars with the option for a solar roof.
I don’t know about the rest of those, but the Hyundai Ioniq 5’s solar roof takes over a decade to pay off at average electricity prices. But if you keep your car parked in the sun for 2 or 3 months, you could get a full battery!
It’s a deceptively simple math problem. You only have so much surface area to cover in solar panels and solar panels only produce so much energy per square meter. You can fit maybe at most a kilowatt of solar panels onto a vehicle if we’re being generous, and those panels aren’t going to have optimum placement for power generation, and solar panels don’t generate their peak output for more than about an hour per day, so the rest of the time will be significantly less than that. Let’s be generous and say 3 kilowatt hours is being generated by those panels in an 8 hour workday of being parked in the sun.
3 kilowatt hours is a lot of energy, but let’s not forget that about 20% will be lost to battery and circuit inefficiency, so 2.6 kilowatts is ultimately useable. But here’s where it really falls apart: electric cars are extremely energy-hungry because cars in general are super inefficient. You’re literally moving a ton of plastic glass and steel around, accelerating and decelerating repeatedly, all to transport on average 1.2 humans. Electric cars consume about 150 watt hours per kilometer in their regulatory tests. Some are more efficient, some are less but no matter what it’s a ton of energy. That generous estimate of 2.6kwh will give you a whole 17 kilometers of range.
In short, the solar panels on electric vehicles are for show. They exist to trick buyers into believing they’re more efficient than they are, and probably they’ll help ensure a parked car doesn’t lose too much range just from sustaining itself while parked. Also private cars are an extremely inefficient method of transportation
the solar panels on electric vehicles are for show
I don’t think that’s a fair take. They are upfront that it provides a trickle charge. But that’s not what matters. Solar tech will get better over time. Eventually this sort of tech will meaningfully extend the range of EVs, and provide enough power in emergency situations.
What about EV’s? Is it a range issue? Makes me think why dont EV’s have solar panels slapped on them?
Someone did the math on the Hyundai Ioniq 5’s solar roof when it came out and I think it was found that best case scenario you get like 5 km of range a day with good weather and the panels will pay off in 10 or 15 years.
Because the w/m2 of a solar panel in optimal conditions (3-400W/m2) when applied to the area of a car is a rounding error compared to the energy consumption of the vehicle itself (5000-20000Wh), and those optimal numbers are degraded massively by the fact that the car can point any direction, and for aerodynamic and style reasons the panel will not have optimal angles even when pointed the right way. Best you could do is offset the 12V load to some degree.
There are cars with panels on the roof but just do the math. It’s a drop in the bucket, unless you live in the tropics and drive very little.
Great that you found a reliable Diesel for 2k.
However this thread is discussing Americans and their Reliance on private cars. They don’t Drive Diesel wagons and don’t pay in EUR.
Gas cars are more numerous having been the norm for over a century. They’re much cheaper and more plentiful on the used market. You’re less likely to find an EV on marketplace or Craigslist, I’ve never seen one there.
What about EV’s? Is it a range issue? Makes me think why dont EV’s have solar panels slapped on them?
I recently attended a lecture on dynamic charging of EVs. Theoretically speaking slapping a solar panel on a car to charge it is feasible, but by putting on solar panels it will add a lot more additional weight and will result in larger wind resistance.
The car would ultimately use more if not the same energy (with the additional energy supplied by the solar panel) then if it didn’t have it in the first place.
Whoever gave that lecture is more than a decade behind the times then. Flexible solar panels exist, and technically the solar cells themselves are very lightweight. It’s generally the protective glass that sandwiches the cells that make up most of the weight.
And these cars already exist. BYD, Hyundai Ionic 5, Toyota Prius Prime, etc, are all production cars with the option for a solar roof.
https://www.techradar.com/news/hyundais-new-electric-car-has-a-solar-panel-roof-and-the-ability-to-charge-other-evs
That article is from 5 years ago.
I don’t know about the rest of those, but the Hyundai Ioniq 5’s solar roof takes over a decade to pay off at average electricity prices. But if you keep your car parked in the sun for 2 or 3 months, you could get a full battery!
If the car lasts over a decade it’s fine, I’d assume it wouldn’t last less than that. But yea that’s still useless
It’s a deceptively simple math problem. You only have so much surface area to cover in solar panels and solar panels only produce so much energy per square meter. You can fit maybe at most a kilowatt of solar panels onto a vehicle if we’re being generous, and those panels aren’t going to have optimum placement for power generation, and solar panels don’t generate their peak output for more than about an hour per day, so the rest of the time will be significantly less than that. Let’s be generous and say 3 kilowatt hours is being generated by those panels in an 8 hour workday of being parked in the sun.
3 kilowatt hours is a lot of energy, but let’s not forget that about 20% will be lost to battery and circuit inefficiency, so 2.6 kilowatts is ultimately useable. But here’s where it really falls apart: electric cars are extremely energy-hungry because cars in general are super inefficient. You’re literally moving a ton of plastic glass and steel around, accelerating and decelerating repeatedly, all to transport on average 1.2 humans. Electric cars consume about 150 watt hours per kilometer in their regulatory tests. Some are more efficient, some are less but no matter what it’s a ton of energy. That generous estimate of 2.6kwh will give you a whole 17 kilometers of range.
In short, the solar panels on electric vehicles are for show. They exist to trick buyers into believing they’re more efficient than they are, and probably they’ll help ensure a parked car doesn’t lose too much range just from sustaining itself while parked. Also private cars are an extremely inefficient method of transportation
I don’t think that’s a fair take. They are upfront that it provides a trickle charge. But that’s not what matters. Solar tech will get better over time. Eventually this sort of tech will meaningfully extend the range of EVs, and provide enough power in emergency situations.
Someone did the math on the Hyundai Ioniq 5’s solar roof when it came out and I think it was found that best case scenario you get like 5 km of range a day with good weather and the panels will pay off in 10 or 15 years.
Because the w/m2 of a solar panel in optimal conditions (3-400W/m2) when applied to the area of a car is a rounding error compared to the energy consumption of the vehicle itself (5000-20000Wh), and those optimal numbers are degraded massively by the fact that the car can point any direction, and for aerodynamic and style reasons the panel will not have optimal angles even when pointed the right way. Best you could do is offset the 12V load to some degree.
There are cars with panels on the roof but just do the math. It’s a drop in the bucket, unless you live in the tropics and drive very little.
Already have
https://www.techradar.com/news/hyundais-new-electric-car-has-a-solar-panel-roof-and-the-ability-to-charge-other-evs
You still need the credit and money to acquire one.
Same is true about gas cars, no?
My diesel wagon cost me under 2k EUR. Point me to a similarly useful (no i-miev or leaf!) EV for under 10k?
Great that you found a reliable Diesel for 2k. However this thread is discussing Americans and their Reliance on private cars. They don’t Drive Diesel wagons and don’t pay in EUR.
Gas cars are more numerous having been the norm for over a century. They’re much cheaper and more plentiful on the used market. You’re less likely to find an EV on marketplace or Craigslist, I’ve never seen one there.