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Solar Powered Car Can Get Close To 60 mph
Jason Sahler writes with this excerpt from Inhabit: "The World Solar Challenge across the Australian outback is coming up, and we're already seeing some truly incredible vehicles going for the gold. Take the Bethany, a solar powered vehicle designed by Cambridge University students. The vehicle is capable of achieving close to 60 miles per hour. Doesn't sound too impressive? Try doing it by using the power required to run a hairdryer."
And I don't think my entire family will fit either.
Athiesm is a religion like not collecting stamps is a hobby.
This is very interesting technology. These solar races really produce odd looking vehicles. Three wheels makes sense in terms of rolling resistance, but I can help but think what might happen if it needed to take a turn fast.
Programs like this are great, and help push the technology envelope. Although it's neat that it can hit 60Mph...the article really does not have much real information in it.
I hope to see some of this technology filter down into production cars. I've always wondered how much power could result from the sunlight hitting the roof of my car all day long when I'm at work. Seems like there is potential missed opportunity there.
-Pete
Soccer Goal Plans
Achieving a sustained speed of over 2 MPH, this beats the previous solar-powered record by over 1 MPH.
Most of the North American Solar Challenge vehicles and World Solar Challenge Vehicles easily exceed 60 mph.
I work on Purdue's Solar team and have first hand experience with these vehicles on the highway.
www.PurdueSolar.org
You are decades from a "sell-able" solar vehicle, if at all. Now get out of the way of my SUV.
There are no loopholes. It's either legal or it's not.
The sun hitting car during work made me think of my grandfather and his solar power lunches. He would put food in a heat proof container and stick it on the the dash of his car when he worked (vine dresser in Californians Central Valley) and every day he would get a hot lunch. Now when I camp I put my cooking water in the sun so it takes less time to boil later...I had a point, but it's lost now.
We are the Borg...
Those HP Logo's could have been solar cells and it would have actually got to 60 rather than close to it
>"Try doing it by using the power required to run a hairdryer."
Hair dryers pull 1000~2000 watts, right? That is a ton. Try having only a few watts to work with...on Mars.
"The transmitter on the lander has a broadcast power of about 14 watts, says Callas. For comparison, the beacon on the Mars Global Surveyor, which is currently in orbit 380 kilometers (228 miles) above the surface of the Red Planet, is weaker -- only 1 watt. Boding poorly for the mission is the fact that this week the sensitive Dish detected the weaker signal from the surveyor, but not the stronger signal from the lander.
But the main problem is the weakness of the signal. And signals weaken as they traverse the roughly 300 million kilometers (about 180 million miles) from Mars to Earth. "We expect a signal hitting the Dish to be something of the order of one billionth of a billionth of a milliwatt [one-thousandth of a watt] of power," says Callas. "It's extremely tiny. This is equivalent to listening to a cell phone from Mars.""
I think (the article is badly written) that the key development is that this car can average almost 60mph. 60mph burst speeds are pretty easily reached in many solar cars. I remember doing about 65 mph back in 1993 in our cars (Dartmouth College's Sunvox I and IV)
Actually going fast is pretty easy so long as your aerodynamics are sound. All you need is enough energy input to counter air resistance and friction from the wheels and you can maintain whatever speed you like. The difficult bit is accelerating to a high speed quickly. It'd be easier to wait until people get over wanting to go fast than design a solar vehicle that can accelerate from a standstill anything like a petrol car.
Fortunately I can see that happening. As the price of driving goes up people's priorities will change.
http://twitter.com/onion2k
The SUN is not a renewable resurse, yu fat laszy swines! When America, under the influinse of Italian agitators, sucks more and more of the sun's rayes for these frivilus sport cars, the rest of the world is plungid into darkness and cold, you greedy rat bastard Italians! I say no more Sun for America until Italy leaves us alone and sends the Pope back to Germany or wherever he cames from.
I'm an electric car.
I don't go very fast,
Or very far.
And if you drive me,
People will think you're gay!
(Solar cars are still electric, it applies dammit!)
I don't know, one could power a small country with the same power needed to run the Spaceballs hair dryer.
And go probably 100. The interesting thing is that having super lightweight cars is really what this whole engineering problem is about. That benefits not just solar power, but any power. If you can run a car off the 1kw, then, that would follow that you could run one off of a 1.4 horsepower engine. That would be roughly the same as what the Amish do, except they just use big horses, so maybe we should just go ask them for fuel efficient designs.
This is my sig.
It gets near 60 once the F-250 rear ends it and pushes it along.
Power source/Sun: at least 1.21 gigawatts. Check.
Speed: 88 miles per hour: Over 2/3 of the way there.
Power conversion to usable form: Nowhere near 1.21 gigawatts available.
I guess I'll have to postpone my time travel a bit.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Let's do the math on this one.
A hair dryer draws around 750 watts, which is a convenient number too, as that's about 1 horsepower. Let's assume the electric motor is 100% efficient too, just for simplicity.
So you're saying the car can do 60MPH on one horsepower.
That's quite doable with a very aerodynamic design and low-friction tires.
But the hill-climbing ability is mighty weak.
One horsepower can lift 550 pounds one foot per second.
So if this vehicle and rider weight 550 pounds, it's going to slow down to 70.7% of 60 MPH if it encounters a hill with a 60 foot rise per mile, just a bit under 1% slope. A 3% slope is going to slow it to a crawl. Not too good anyplace but Kansas.
And no, you don't get it all back on the downhill slope.
What they don't mention: you have to get so close to the sun that the tyres melts.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
80 hp = 60000 watts, maybe 40-100 hairdryers
I don't know what kind of point you are trying to make here, since you've totally left the ball field.
That car won't be passing any crash tests soon. I still appreciate it as a fine piece of engineering, though.
Using NiMH batteries.
http://en.wikipedia.org/wiki/Solectria_Sunrise
http://www.sunrise-ev.com/
Everyone else is just re-inventing the wheel.
The best place of solar panels is on the roof of your house, charging up a battery bank you can use to charge the car when you park it.
Deleted
UQ's Sunshark could do more than 80 mph in '99, and we were by no means the fastest solar car on the highway.
Averaging 60 mph would at least put these folks up with the race leaders under the rules for more recent races*, but that isn't what the article appears to be claiming.
*http://en.wikipedia.org/wiki/World_Solar_Challenge
So, briefly skimming the article, it's about the solar challenge.
60 MPH is squat.
Previous winner Nuna 4 did almost 90, as it had a top speed of 142 km/h (or 88MPH)
The version before that did an average of 63.8 MPH for the entire race. (after that they changed the rules)
So what's the news value of this?
have the rules changed for this years solar challenge?
But untill these cars are mainstream, I WILL put large, thick pieces of dark paper on top of people's panels while they're parked to piss them off. You have my word.