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Missouri Wins American Solar Challenge
dagoalieman writes "The University of Missouri - Rolla won this year's 2300 mile American Solar Challenge. The roughly 339lb car (517lb with driver) with 1500 watts of power won by nearly 5 hours - here's the final results. UMR has now won two out of the past three races, finishing second in the last race, to Michigan. Congrats, and good luck to them in the World Solar Challenge!"
Overall Results
The leader finished with 56:10:46, while this year's leader finished with 51:47:39. However, looking at the overall top 10, it appears that the 2001 field was slightly better than the top 10 of this year's field. I'd say it means that solar technology is advancing but at a somewhat slow pace. Until we hit that breakthrough that gets the solar efficiency past 40%, we won't see much of any daily applications of this tech.
Then again, it's just my opinion, I could be wrong.
-Cyc
/.'s 10 Millionth
Some cars have translucent solar cells embedded in their sunroofs. It first arrived on the now discontinued Mazda 929 and current Audi A6's and A8's have it. To give you an idea of the power generated, it was only used to power the fans to circulate air to cool the car down when it was sitting out in the sun.
Well the specs in the Slashdot blurb are a little off. According to the Univ of Missouri site, it weighs 822 lbs with driver. Of that 176 lbs is the driver and 320 lbs is batteries.
A Prius has about the same surface area as one of these solar racers. If you covered the entire car with solar cells, you'd get about the same power, 1500W max in bright sunlight at high noon. That's about 2HP which is less power than a 50cc moped, maybe as much power as a lawnmower, and maybe as much power as 3-4 professional bicycle racers. 2HP might be enough to run the headlights and A/C, but forget about it for moving 3000lbs of car + passengers.
1500 watts would be absolutely useless to any type of consumer vehicle. That's 2 horsepower. Your (push) lawnmower has more power. Try riding that across country.
Besides, I'm sure they're using ultra-light ultra-expensive solar cells that you couldn't afford. The things you put on your house would barely generate enough energy to compensate for their own weight.
"I assumed blithely that there were no elves out there in the darkness"
I used to be on the Solar Race car team at UT, and I can tell you that the rules for this and Sunrayce are extremely restrictive as to what kind of cells and batteries you can use (to keep the rich schools from buying all the super-top-of-the-line stuff and outspending the competition), and you're limited to driving the speed limit. It's more of a competition about making a car that won't break down than about speed.
I don't know where you're getting your specs but the headline is correct. Our batteries weigh 30kg (66 lbs) as per race rules. Maybe you're thinking of an old lead-acid based car. This car uses lithium-ion polymer batteries.
And as for the question about the solar cells, they're certainly the single most expensive part of the car, but they're really not that bad. They're gallium arsenide cells sold to us at a steep discount by Spectrolab because they were rejected for use on satellites, but even their rejects are much better than standard silicon terrestrial-grade cells (which incidentally is what we won second with in 2001). The full grade cells run in the millions of dollars, but reject cells like ours can be found in the ballpark of tens of thousands. The bare cells themselves are not significantly thinner or lighter than any other type of cell, but I guarantee the packaging and encapsulation is.
What is the current progress on this?
4 21.html
This is what I found:
http://sharp-world.com/corporate/news/030
"17.4% Module Conversion Efficiency Industry's Most Efficient --- April 21, 2003"
"17.3 m2 of area yielding 3.01 kW (4hp)"
The surface area (hood, roof) of a 2004 Prius is ~10m^2. So that would generate around 2kW with these panels.
What are the projection for panel efficiency over the next 5-20 years?
At 50% efficiency you could get 5kW output for a 10m^2 panel. If you drove 1 hour/day and parked in the sun 6 hours/day you could generate an extra 40hp for that hour on the road. As someone mentioned earlier, slap this on a Prius and you should reach 100mpg+ easily.
Feel free to fix any calculation errors.
Whenever the offence inspires less horror than the punishment, the rigour of penal law is obliged to give way...
Actually, the rules for solar races almost always place a limit on the $/watt for the cells, so that competitors can't "buy" the win. (there are some much more efficient solar cells out there, but their cost is insanely high) This forces entrants to work on "the big picture", including vehicle weight, aerodynamics, electronics efficiency, and even their strategy. Many solar competitions allow one battery swap-out during the course of the run, and teams have to decide when the best time for this is, in addition to how hard to push the pedal when power's running low.
I work for the Department of Redundancy Department.