You can install our site as a web app on your iOS device by utilizing the Add to Home Screen feature in Safari. Please see this thread for more details on this.
Note: This feature currently requires accessing the site using the built-in Safari browser.
I think several of us are possibly being a bit absolutist in thinking. Certainly the highest currently available commercial efficiencies in solar panels are around the Sharp triple-junction at 37.9%. The latest developments seem to show Perovskite layers could add as much as 50% to efficiency, assuming the durability and other issues can be resolves, so might end out with commercial efficiency of more than 50%. Assume that happens, still a car will not have enough space for that to be useful in most populated latitudes. ... So, yes, there will be some solar panels on transport vehicles of some sort within the next decade.
Now, I will record my predictions and will happily make book that these things will happen one way or another.
Comments (sorry if I come off harsh):
1. Obviously the answer is never, due to the laws of physics.
2. Obviusly number 2: the answer is "now" as in there are solar powered cars and lot's of them. Only the panels are on a roof where they can be used most effectively and the electricity is stored in this device on-board the vehicle known as a "battery" (go figure).
It might "never" make sense in Norway because the physics don't seem to work and there just isn't that much sun hitting the earth, but in Texas or North Africa?
Even with theoretical 100% efficient panels at perfect angels toward the sun all the time there just isn't enough solar energy hitting the surface area of a normal sized car.
Enthusiasm doesn't beat the laws of thermodynamics, sorry to be a Debbie downer.
On a side note, I chuckle a little when I see people with grid tied system saying they power their cars from solar. Good effort, but probably not actually true.
If you purchase a wind or solar plan from your electric company, you force them to purchase that much wind and/or solar power. In many cases, unless you force them to by choosing that plan, they won't purchase any. So although the actual electrons powering your car may not be from solar or wind sources, the amount of energy you use has been put into the grid from those sources (and that much less fossil fuel energy has been used).
I was in college during the American Tour de Sol days (late 80's), and had friends who worked on Dartmouth's entry (the various SunVox cars). None of the entries were anything you'd consider "practical". I tried to find pictures, but no luck. Dartmouth has a bunch of stuff cataloged, but it's all 35mm film/prints - nothing on line.Is it theoretically possible to build a vehicle that can move at freeway speeds on just sunlight? Absolutely - SunRaycer proved it - with 1980s technology it could do 68 mph under ideal conditions - in a single person teardrop that weighed less than 600 pounds with one powered wheel and no chance in any collision. But they averaged less than 45 mph for the race, and it is in no way a practical vehicle for anyone.
Correct. The average energy reaching the ground worldwide is about** 340 W/m[SUP]2[/SUP]. At the equator it can be 1000 W/m[SUP]2[/SUP]. This is on a clear day at noon. Austin, TX gets a total of 4800 W/m[SUP]2[/SUP] per day on average which can be used to generate electricity (for those that don't know, Austin is close to the geographical centre of Texas). That works out to a Tesla driving distance of about 31 km (19 miles) per m[SUP]2[/SUP] of car solar panel surface (and assumes a 100% efficient, perfectly oriented, solar panel that doesn't increase the current weight of the car).
** These are the best numbers I could come up with in a short time. If anyone has any better numbers, go for it.
Okay let's use your numbers for a minute here and look at a scenario. Let's figure we're in Austin in 2025 and we get 4800 w/m^2 sun per day on average. We've got a 2025 model s with the same dimensions as today 16x6ft, roughly 10m^2 horizontal surface area. If you average 4.8kwh/m^2 and you've got 10m^2 at 50% efficiency, that gets you 24kwh a day right?