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Solar Powered Car Can Get Close To 60 mph

timothy posted more than 5 years ago | from the australians-still-on-about-transportation dept.

Transportation 119

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."

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But how does it do in the crash test? (4, Funny)

InsaneProcessor (869563) | more than 5 years ago | (#27490099)

And I don't think my entire family will fit either.

Re:But how does it do in the crash test? (5, Funny)

Thanshin (1188877) | more than 5 years ago | (#27490167)

does it do in the crash test? And I don't think my entire family will fit either.

Are you looking for a car? Or for an alibi.

Re:But how does it do in the crash test? (0)

Anonymous Coward | more than 5 years ago | (#27491465)

I don't think the parent would have been modded funny if you hadn't made it look that way. I'm pretty sure he was completely serious on two separate points.

Re:But how does it do in the crash test? (0)

Anonymous Coward | more than 5 years ago | (#27490347)

It's a race car (albeit slow one). Generally entire families do not fit in race cars.

Re:But how does it do in the crash test? (4, Insightful)

Nutria (679911) | more than 5 years ago | (#27490379)

And I don't think my entire family will fit either.

Or groceries or luggage, or run on a cloudy day.

Solar auto challenges should be viewed as nothing more than useful engineer training that serves no immediate practical purpose, just as having my CompSci prof give me a large Senior Project, that I haven't used in my professional life, but gave me a solid foundation on which to grow.

Re:But how does it do in the crash test? (0)

reashlin (1370169) | more than 5 years ago | (#27491103)

Because nothing good has ever come from people trying to push technology to its limits, learning new things as they go and passing that technology on to cheaper applications. Thus making money and then using that to make a better product pushing it down to a lower price and repeating.

Re:But how does it do in the crash test? (2, Insightful)

cool_story_bro (1522525) | more than 5 years ago | (#27491699)

I think you have a shaky grasp on the term immediate practical purpose. I'm fairly certain the GP meant that these solar powered race cars aren't going to finish their race and go straight into production for retail consumption

Re:But how does it do in the crash test? (4, Insightful)

Simon Brooke (45012) | more than 5 years ago | (#27492117)

Solar auto challenges should be viewed as nothing more than useful engineer training that serves no immediate practical purpose...

Disagree.

Granted solar power is not suitable for actual every day transportation in most parts of the world, a great deal of the engineering of these cars will move into the mainstream - and sooner than you think. As fuel gets more expensive, cars will have to get much lighter, much more aerodynamic, and have much lower rolling resistance. Many of them will use battery or hybrid power systems, and regenerative braking will become commonplace. Solar cars are pioneering all these technologies.

Re:But how does it do in the crash test? (1)

MasseKid (1294554) | more than 5 years ago | (#27494025)

I beg to differ. There are companies that are developing ways to make more fuel efficient cars. Those budgets combined are on a different order of magnitude than the budget a group of college kids get to hobble together a car. Those companies are the ones that are shaping the future. I don't think ANY of the solar cars are using regenerative braking as the weight cost would never be repaid as these cars don't stop but once a race. Furthermore you make a critically bad assumption. Fuel does not have to get more expensive. In fact, with a good battery, i.e. hydrogen, you can make power more efficiently at a power plant and the total energy cost can decrease. This in turn will lower the demand for oil and lower the price of oil.

Re:But how does it do in the crash test? (0)

Nutria (679911) | more than 5 years ago | (#27494235)

with a good battery, i.e. hydrogen, you can make power more efficiently at a power plant and the total energy cost can decrease.

Except that we (only in the US, or does it happen all over the world?) lose something like 50% loss from transmission.

What I, IMNSHO, think we need are smaller NG nuke plants closer to population centers. Higher efficiency thru less transmission loss, but more sites to protect from Bad Guys.

Re:But how does it do in the crash test? (1)

MasseKid (1294554) | more than 5 years ago | (#27495513)

Wiki says... [QUOTE=wiki] Transmission and distribution losses in the USA were estimated at 7.2% in 1995 [2], and in the UK at 7.4% in 1998. [3] [/QUOTE] :shrug:

Re:But how does it do in the crash test? (1)

topnob (1195249) | more than 5 years ago | (#27497445)

What they don't have to brake when going around corners... wait I think they do! :D

EV's could do 375 miles per charge in 1997 (3, Insightful)

Colin Smith (2679) | more than 5 years ago | (#27494385)

Using NiMH batteries.

http://en.wikipedia.org/wiki/Solectria_Sunrise [wikipedia.org]

http://www.sunrise-ev.com/ [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.
 

Re:But how does it do in the crash test? (1)

evilviper (135110) | more than 5 years ago | (#27494595)

a great deal of the engineering of these cars will move into the mainstream - and sooner than you think.

What new engineering is needed for a normal car?

Electric motors have been 99%+ efficient for a very long time.

Low rolling resistance merely means a STIFF tire. You'll never see lower rolling resistance than solid steel train wheels, which have been around forever. For road traction, a thin layer of a gripping material, like tire rubber, is all that is required for performance and safety (if you don't mind the horrible ride).

Top speed, as quoted in the article, is nearly complete nonsense. Ignoring air resistance, there is NOTHING to limit your top speed. Any amount of power will eventually accelerate you to any speed.

Aerodynamics is the important part of electric cars, and these rolling-wing designs aren't suitable for adaptation into consumer vehicles without complete redesign.

Re:But how does it do in the crash test? (1)

geekoid (135745) | more than 5 years ago | (#27495103)

"...- and sooner than you think."

So not immediate? like the poster said.

These solar cars do not pioneer any of that in any practical way.

Re:But how does it do in the crash test? (0)

Anonymous Coward | more than 5 years ago | (#27497027)

The poster actually said solar *challenges* were worthless, and I agree with him. I knew before clicking on the link that the car we'd see was the same old flat spaceship fitted to a bicycle we've seen for nearly 20 years. I'll bet dollars to doughnuts the only reason this system is faster is more efficient solar cell technology now. BFD... come back when you can make the thing actually haul something reasonable... like how about oh I dunno... 2 people instead of one.

Re:But how does it do in the crash test? (0)

Anonymous Coward | more than 5 years ago | (#27490719)

Yes... and can it fly or go underwater?

Re:But how does it do in the crash test? (0)

Anonymous Coward | more than 5 years ago | (#27491193)

But will it run Linux?

Re:But how does it do in the crash test? (3, Insightful)

Alioth (221270) | more than 5 years ago | (#27492385)

It's a racing car. Your family and your groceries won't fit in a Formula 1 car or Indy car either. It's not supposed to be a family car or anything approximating that, it's for racing.

Re:But how does it do in the crash test? (0)

Anonymous Coward | more than 5 years ago | (#27493967)

All right.

Build me a solar car that at any time can take four people and a few bags at least 250 miles in one sitting then.

Re:But how does it do in the crash test? (1)

RollingThunder (88952) | more than 5 years ago | (#27496191)

How many football fields worth of solar panels will you let me stick out over the front and back of it? ;)

Re:But how does it do in the crash test? (2, Funny)

Endo13 (1000782) | more than 5 years ago | (#27492491)

And I don't think my entire family will fit either.

Imagine a beowulf cluster of them!

Re:But how does it do in the crash test? (0)

Anonymous Coward | more than 5 years ago | (#27494381)

If it's like the new GM/SegWay concept it won't need to do crash tests. They will never crash, it's claimed.

Pushing the limits of tech (4, Interesting)

peterdaly (123554) | more than 5 years ago | (#27490109)

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

Re:Pushing the limits of tech (1)

Thanshin (1188877) | more than 5 years ago | (#27490245)

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.

I've always wondered how much power could result from the sunlight hitting the road my car is on most of times it actually needs power.

Sun power durring the workday (1)

Anonymous Monkey (795756) | more than 5 years ago | (#27490269)

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.

Re:Sun power durring the workday (1)

Mprx (82435) | more than 5 years ago | (#27490423)

You may be interested in this:

http://solarcooking.wikia.com/ [wikia.com]

Solar cooking isn't practical in every climate, but when it works it can be very effective.

Re:Sun power durring the workday (1)

xaxa (988988) | more than 5 years ago | (#27491527)

I've seen solar cooking work in England, just from a friend making a solar oven out of a box, aluminium foil and black paint (IIRC).

No doubt it's a lot quicker in southern California. (And in England it's not going to work too well in the winter, or on dull days.)

Re:Pushing the limits of tech (0)

Anonymous Coward | more than 5 years ago | (#27490277)

This is where people can really learn from TV. THIS [wikipedia.org] car has already showed how unstable 3 wheels are - in countless episodes of Mr. Bean.

Re:Pushing the limits of tech (1)

Rei (128717) | more than 5 years ago | (#27492571)

Oooh, is it anecdote time already? Well, then, this car [duxbury.ma.us] has shown how unstable 4 wheels are, this car [firepinto.com] has shown how gasoline cars are inherently unsafe, and this person [makefive.com] has shown how white people are cannibals. Gotta love how that works! ;)

FYI... [autospeed.com]

(Yes, I know you were kidding... but it's a popular misconception, so I thought it should be addressed)

Re:Pushing the limits of tech (1)

Quantos (1327889) | more than 5 years ago | (#27493115)

It is a misconception that three wheels are more unstable than four wheels. One example of this is well demonstrated by a forklift.
With a forklift what keeps it stable is the center of balance being inside a certain dimension, generally found by making a pyramid that runs on the base from the center of the back of the lift truck to the center and outside of the front axle, the peak of the pyramid extends to the top of the mast - so it will vary depending on how high the load is. This makes sense if you are looking at a three wheeled forklift.
Amazingly they calculate the pyramid the same way with a four wheeled forklift.
Someone with engineering experience could probably have explained this a little easier, or at least more coherently, but hopefully this adds something.
Of course this may not apply to something with the solitary wheel being in the front when you are trying to navigate a corner at higher speeds.

Re:Pushing the limits of tech (0)

Anonymous Coward | more than 5 years ago | (#27493455)

Exactly.. That is part of the reason why quads took over from trikes. Higher speeds definitely play a fairly large factor.

Re:Pushing the limits of tech (3, Insightful)

cplusplus (782679) | more than 5 years ago | (#27490281)

I've had the same thought. I'd love to be able to drive to work in a plug-in vehicle of some sort, park the car in the sun all day and let it passively recharge, and then drive home using that free power. The only thing the sun does for my car now is make the interior too damn hot (even with window tint and a sun shade).

Re:Pushing the limits of tech (2, Informative)

Rei (128717) | more than 5 years ago | (#27492041)

Sorry, but not with current physics.

A typical streamlined EV, like the Volt, the MiEV, or the Roadster, will use about 200Wh/mi. Let's go with 220Wh/mi wall to wheels, since some is lost in charging. Let's assume a very efficient panel (20% *after* accounting for the cells not all fitting perfectly together) and a large, flat area (2' x 4' ~= 0.74 square meters). Let's say that it's perfectly sunny (1000W/m^2), there's no shade, and let's be optimistic and say that the cosine-weighted average angle of the sun to your car is 50 degrees over the course of a 9 hour work day. Ready? 1000W/m^2 * 0.74m^2 * cos(50 degrees) * 20% efficiency * 9 hours / (220Wh/mi) = 3.9 miles.

Not exactly a long distance for this very favorable case, ne?

Put solar cells on the roof where they belong -- where they're not requiring space/aero compromises, weighing your vehicle down, more likely to be shaded, and more likely to be at the wrong angle.

Re:Pushing the limits of tech (1)

AnotherBlackHat (265897) | more than 5 years ago | (#27493301)

a large, flat area (2' x 4' ~= 0.74 square meters)

If you're going to be crazy optimistic in your other assumptions, you might as well assume a flexible solar cell car cover, with 3 times that area.
Or you could carry a folding 4x8 canopy and go all the way to 15 miles.

Re:Pushing the limits of tech (0)

Anonymous Coward | more than 5 years ago | (#27493705)

Or you can buy a 1996 Audi A8, it has solar panels in the sunroof that power a dehumidifier to keep the interior cooler during hot days.....

Re:Pushing the limits of tech (1)

Rei (128717) | more than 5 years ago | (#27495157)

The more curves the panels go over, the less light they'll capture.

As for a canopy, yes, it makes more sense, but still not as much sense as just having the panels on your roof. Not to mention that most flexible cells aren't as efficient as rigid ones. Nor will that canopy be particularly lightweight or easy to handle -- just the opposite.

Re:Pushing the limits of tech (1)

Carnildo (712617) | more than 5 years ago | (#27495895)

A typical streamlined EV, like the Volt, the MiEV, or the Roadster, will use about 200Wh/mi. Let's go with 220Wh/mi wall to wheels, since some is lost in charging. Let's assume a very efficient panel (20% *after* accounting for the cells not all fitting perfectly together) and a large, flat area (2' x 4' ~= 0.74 square meters). Let's say that it's perfectly sunny (1000W/m^2), there's no shade, and let's be optimistic and say that the cosine-weighted average angle of the sun to your car is 50 degrees over the course of a 9 hour work day. Ready? 1000W/m^2 * 0.74m^2 * cos(50 degrees) * 20% efficiency * 9 hours / (220Wh/mi) = 3.9 miles.

You're being overly pessimstic about the available area. My Honda Civic (a relatively small car) is 14 feet long by 5 feet wide, for about 6.5 square meters of footprint. Assuming I'm carrying a foldable solar array with a suitable support frame, that gives me 35 miles. Since it's on a support frame rather than embedded into the roof, I could tilt the frame to get a better angle (say, a weighted average of 35 degrees): 44 miles.

Re:Pushing the limits of tech (1)

Rei (128717) | more than 5 years ago | (#27497647)

Well, that's a completely different proposal, now isn't it? :) On the car, you're limited by available flat surface area. And do you know how heavy and complicated of a proposition that is you're talking about -- a portable support frame that'll stand up to whatever winds or whatnot come along, with that much solar cell material? And if your answer to save weight (ignoring the frame) is "thin film", cut your efficiency in half.

Re:Pushing the limits of tech (0)

Anonymous Coward | more than 5 years ago | (#27497563)

I DID put a 120w solar panel on the roof of my 15 passenger van. It got 13 mpg (after some tuning and an MSD ignition). It now gets 14.5 on sunny days. Now, that's not a great example but it's kind of in the range. A 120w panel is about 1/4 hp in full sun (or a little less). So, no, you're not going to get enough charge out of this thing which is about 2 feet by a little over 4 ft in size. Newer panels are incrementally better, but not tons. Even though in my case, the panel is "in the wind" and no doubt causing more wind resistance even at the low speeds this thing mostly goes, I get this pretty significant milage improvement (about 11%), and you can feel it in how hard you have to push the gas pedal -- not as hard.

But it would like like junk on my 2001 buick LeSabre, which already gets 26.1 mpg if I don't turn up the multi KW stereo too much. And this is a "spin the tires on command" car. It's all how you actually drive at some point.

Car alternators are junk, inefficient, to save weight. There's a lot of room for improvement there, and letting the driver turn off parasitic loads (like fans that always run).

Note: This solar panel, a Solarex, was a spare from my house/shop/lab system which works great, but then again we are frugal and have 16 of them up there...Old tech from 20 years back -- it works fine, just like new. www.coultersmithing.com (which probably can't take a slashdotting so I didn't make it easy)

Re:Pushing the limits of tech (2, Interesting)

hedwards (940851) | more than 5 years ago | (#27490289)

If you need to turn that fast you're probably screwed anyways. The friction on the front tires hasn't been the limiting factor for quite some time.

The much bigger problems are weight distribution and the rate at which the wheels spin with respect to each other. Hence the addition of http://en.wikipedia.org/wiki/Electronic_stability_control [wikipedia.org] for more information.

And with only 3 wheels, that latter concern is easier to deal with than with the extra wheel.

Re:Pushing the limits of tech (0)

Anonymous Coward | more than 5 years ago | (#27491557)

You can corner balance (raise/lower the 4 corners of your shocks/springs) to fiddle with weight distribution. You can also move ballast around (i.e. move the batteries) to fiddle with weight distribution.

Personally, I think ESC is a poor man's version of limtied slip differentials. ESC works by hitting the brakes. I want to go fast, not have the computer slow me down. :)

Re:Pushing the limits of tech (0)

Anonymous Coward | more than 5 years ago | (#27491891)

ESC works by hitting the brakes.

That's ABS.

Re:Pushing the limits of tech (0)

Anonymous Coward | more than 5 years ago | (#27490711)

Programs like this are great

No they are not. Programs like this are a waste of time and money (and probably OUR TAX MONEY). There is absolutely NOTHING wrong with the existing car industry, but the enviro-nazi's, greenpeace style terrorist organizations and well financed special interest groups have all succeeded in portraying cars as something to be feared. This is 100% wrong, unfortunately saying this simple truth in public these days gets you lynched as no doubt this post will be.

Re:Pushing the limits of tech (1)

somersault (912633) | more than 5 years ago | (#27491019)

This is 100% wrong

If you started realising that the world doesn't operate in absolutes, perhaps you wouldn't be a troll anymore. It is incredible how much oil we use and waste (millions of tons of plastic bags, 'gas', etc). There is absolutely nothing wrong with wanting to be more efficient in our use of resources, global warming or no global warming.

Re:Pushing the limits of tech (0)

Anonymous Coward | more than 5 years ago | (#27491421)

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

Turning on three wheels shouldn't be an issue. If the front two wheels are staggered out and especially if the car is RWD, it's much easier to rotate a three wheeled car than a four wheeled car. A lot of FWD and AWD race cars stagger their front wheels for this reason.

Re:Pushing the limits of tech (2, Interesting)

Rei (128717) | more than 5 years ago | (#27491897)

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.

Just because it's three wheeled, or because it's this specific car? Three wheelers can be extremely stable [autospeed.com] .

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.

The missed opportunity would be to put those precious solar cells on top of a car where you have to carry the weight around and the angles are poor rather than on a rooftop where you don't have to haul the weight around and where they can be positioned at an optimum angle.

Re:Pushing the limits of tech (1)

Grishnakh (216268) | more than 5 years ago | (#27492261)

While I think we definitely need to do something as far as our transportation infrastructure, these solar-powered cars seem about as useful to me as radio-control cars (the kind that are 1-2 feet long) which can go 60mph. 60mph is not a great achievement, since it's easy to do that with a small R/C car running on a battery. Of course, someone will probably say a 40-pound R/C car can't carry a human passenger, and that's true, but that R/C car really has about the same utility as one of these solar-powered cars, which are little more than motor-powered bicycles. The whole thing is just a big waste of time, as these cars will never be able to serve as useful vehicles; there simply isn't enough power in the sunlight hitting the rooftop of any small vehicle, no matter how efficient your solar cells are.

There's two things that can really improve transportation:
1) More solar power, combined with electric vehicles. While the rooftop of a small car doesn't have much area, the rooftop of an office building, shopping center, parking garage, or even a typical house has tons of area. There's a lot of real estate in our cities that can be covered with solar panels and used to provide cheap electricity to the grid. If we simply had better battery technology, so we could store perhaps 10x the energy of today's batteries, we'd easily be able to build practical electric vehicles to replace our current fossil-fuel powered ones, and we could power them with the clean, cheap electricity generated by all these rooftop solar panels.

2) Personal Rapid Transit (PRT), such as SkyTran [skytran.net] , where small, electric-powered cars travel on suspended rails and are fully automated. We already have all the technology needed to build this, we just need the capital to implement it. Not only would this use far less energy than our current fossil-fuel infrastructure, it would alleviate traffic congestion entirely, cost far less than personal vehicles and roads and highways, and take us where we need to go much faster as these cars can go 100+mph and don't have to stop for stop lights.

As a society, we need to be dedicated funding and effort towards useful, practical projects and technologies such as these, not useless technologies such as these solar-powered bicycles which will never be a practical alternative to modern transportation.

Nice (0)

Anonymous Coward | more than 5 years ago | (#27490135)

Achieving a sustained speed of over 2 MPH, this beats the previous solar-powered record by over 1 MPH.

No, not impressed. (4, Informative)

gblackwo (1087063) | more than 5 years ago | (#27490143)

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

Re:No, not impressed. (1)

caramelcarrot (778148) | more than 5 years ago | (#27490253)

There ain't much sun in Cambridge.

Re:No, not impressed. (4, Interesting)

oneiros27 (46144) | more than 5 years ago | (#27490505)

I was on the GW solar car team more than 10 years ago -- we could do 60mph back then, so I'm not impressed, either.

The important factors included: how much sun is there are the time, are you willing to drain the batteries, and are we going uphill?

If you've got good sun, don't have a screwed up array like we did in the '95 Sunrayce, and are willing to drain your batteries, it's easy to go over 60mph. And if you're going downhill, it's even easier.

Of course, that year they decided to put the finish line at the top of a mountain, and we had mostly clouds for the last few days, so just about everyone showed poorly overall.

Re:No, not impressed. (0)

Anonymous Coward | more than 5 years ago | (#27491301)

The average speed of the WSC winners is roughly at the 60 MPH level:
http://en.wikipedia.org/wiki/World_Solar_Challenge

Re:No, not impressed. (0)

Anonymous Coward | more than 5 years ago | (#27491655)

60mph is a rough _cruising_ speed, not the maximum speed.

Re:No, not impressed. (0)

Anonymous Coward | more than 5 years ago | (#27492805)

The University of Minnesota's Borealis 2 could hit 78MPH, although it wouldn't be able to maintain power at that speed even on a 100% day. I drove lead for that caravan during testing, and was always a little worried I'd get nabbed for doing 20 over in a 55.

Ashia's solar vehicle that participated in the World Solar Rally in Taiwan topped out on one stretch of the course at around 89 MPH...needless to say they took 1st place in the circuit race and cross country. =/.

So, I agree...I'm not impressed...unless it looks like a real car and can tow a boat or something.

Which means for the greenies... (0, Troll)

Capt James McCarthy (860294) | more than 5 years ago | (#27490223)

You are decades from a "sell-able" solar vehicle, if at all. Now get out of the way of my SUV.

Re:Which means for the greenies... (4, Insightful)

CannedTurkey (920516) | more than 5 years ago | (#27490303)

Get your SUV out of the way of my progress.

Re:Which means for the greenies... (1)

tnk1 (899206) | more than 5 years ago | (#27490375)

Solar is great for power generation when you can be sure you'll be in one place that gets a ton of sunlight. That's generally not something you're going to get with a car.

So, practical applications of all-solar cars? Probably never. Still, pushing the envelope so that you can use solar power for components or extra power is a good idea. Why let all that roof space go to waste on your car?

I bet that SUV has quite a few square feet of prime real estate. :)

Re:Which means for the greenies... (3, Interesting)

jellomizer (103300) | more than 5 years ago | (#27490435)

I doubt we will see a sell-able fully solar powered car in our lifetime. As there are many concepts that make it impractical
Night Driving
Garages
Extended periods of poor weather.
Tree Coverage
Building coverage in Cities

However out of these competitions we come with a lot of good technology more then just solar power. The fact that you car powered off the energy of a hair dryer. Could be used in many mechanical devices longer lasting battery powered devices. Heck they could use the technology and make a more efficient hair dryer.

Re:Which means for the greenies... (1)

iampiti (1059688) | more than 5 years ago | (#27491869)

Not fully solar but I don't see why a mixed solar/pluggable electric could not work. Moreover, I believe it would be a good idea: You charge the batteries with the sun as much as you can and the rest comes from the grid

Re:Which means for the greenies... (1)

Rei (128717) | more than 5 years ago | (#27492177)

Personally, when it comes to practical implementations, I expect to see solar cells on the top of RVs and semis long before on cars. Lots more flat real-estate up there. Plus it'd be easier to extend eaves and have actuated positioning of the cells when parked.

Note that this doesn't mean "100% solar powered RVs and semis". It'd be purely supplemental at best, unless we can get up into the 80% efficiency range, wherein you might be able to get that for RVs or unloaded semis. And even then, it'd take some herculean efforts in terms of weight reduction and streamlining to have 100% solar power and still have a desirable vehicle.

Re:Which means for the greenies... (1)

fred fleenblat (463628) | more than 5 years ago | (#27492917)

Many RV's already have a modest solar panel on the roof. Their primary use is to keep the batteries topped up while the unit is storage.

Sponsorship (3, Insightful)

ickleberry (864871) | more than 5 years ago | (#27490275)

Those HP Logo's could have been solar cells and it would have actually got to 60 rather than close to it

Big whoop (2, Interesting)

djupedal (584558) | more than 5 years ago | (#27490315)

>"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. [xs4all.nl]

"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.""

Re:Big whoop (1)

Thanshin (1188877) | more than 5 years ago | (#27490433)

"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.""

"An extremely tiny cell phone." says Callas "With both hands tied to your back. And a hearing problem. And a crappy telco that hangs the calls if you speak the word "Midget"."

Re:Big whoop (0)

Anonymous Coward | more than 5 years ago | (#27495919)

...And we LIKED IT!

Re:Big whoop (1)

ivan256 (17499) | more than 5 years ago | (#27492351)

Exactly. Want your average engineering student to build something that can hit 60 mph on 1000 watts? No problem.

The question is.... How long does it take to get to 1000 watts.

I've seen some pretty impressive cars powered by 2HP steam engines. They could go really fast.... But it took them several minutes to accelerate to top speed.

Re:Big whoop (1)

ivan256 (17499) | more than 5 years ago | (#27492653)

Duh. Think-o...

"How long does it take to get to 60mph"....

I previewed, and it looked right... Then as I browsed away from the comment the "oh-shit" kicked in...

Re:Big whoop (2, Funny)

R3d M3rcury (871886) | more than 5 years ago | (#27494421)

Hair dryers pull 1000~2000 watts, right? That is a ton. Try having only a few watts to work with...

You had a few watts?! LUXURY! Why, when I was a boy, we had to generate our own electricity by walking up hill to school! Both ways!

But try to explain that to the kids today...

Re:Big whoop (1)

MasseKid (1294554) | more than 5 years ago | (#27495913)

Umm... that's transmitted power. That has nothing to do with how much energy the mars rover is using. Hell, it's using around 150 watts to generate that 14 watt transmition signal. 14 Watts is what you would expect a small dish to transmit from earth's surface to a satalite.

60mph Average (5, Informative)

zlexiss (14056) | more than 5 years ago | (#27490321)

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)

Re:60mph Average (1)

drinkypoo (153816) | more than 5 years ago | (#27490705)

That's actually pretty incredible, but it would be more relevant to know how useful solar can be in the case of a feasible production vehicle. Don't forget to park facing the Equator (with variation for time of day) to gain maximum insolation! :) So far I think the best application is a golf course; all the carts could have a solar charger on them, and you could tie them all to the grid. It doesn't have to be expensive, if it's built in.

Re:60mph Average (1)

mkbosmans (1091203) | more than 5 years ago | (#27494343)

60 mph on average isn't anything new either, the Dutch University of Delft team did an average of 103 km/h during the 2005 Solar Challenge with their Nuna [wikipedia.org] car. The solar car they will use this year is two generation further, so probably will go even faster.

Going fast is easy. (4, Insightful)

onion2k (203094) | more than 5 years ago | (#27490323)

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.

Re:Going fast is easy. (2, Interesting)

prefect42 (141309) | more than 5 years ago | (#27490551)

But surely systems like KERS show that with only a small weight penalty (from around 25kg), and a decent amount of power (~80bhp), you can already get there. Now as long as you don't need to be using that often, and can simply clutch it out while not using it, it's just 25kg of dead weight while trying to be efficient.

This is assuming that you've got another much more efficient lower powered motor for the rest of the time.

25kg just isn't such a huge weight to carry in any vehicle intended to carry 2+ people, and you don't need that much power to make a car perfectly good to drive, as long as it's not stupidly heavy.

80 hp is way more than you have available (1)

Khashishi (775369) | more than 5 years ago | (#27493771)

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.

Re:Going fast is easy. (1)

drinkypoo (153816) | more than 5 years ago | (#27490627)

Actually the optimal aerodynamic characteristics are different at high and low speeds. Also going fast is a lot more challenging because you ask a lot more of the tires, and all of these crazy-high-mileage vehicles have special tires which are either very expensive and short-lived, or have very little traction compared to what's on a typical passenger car like a Ford Taurus or Toyota Camry.

Re:Going fast is easy. (2, Insightful)

Rei (128717) | more than 5 years ago | (#27492485)

Yeah. Note what happens when you try to take these sort of concepts from "crazy hypercar" to "usable vehicle". Compare, for example, Pac Car II [web.psi.ch] to the Aptera 2e [aptera2e.org] . Same basic design philosophy, but the 2e has to be usable on city streets, hold two passengers and a good amount of cargo comfortably, be practical to mass produce, have proper acceleration and range, and in general have the amenities and safety people expect in a car. And the net result is that you go from a drag coefficient of 0.06-ish to one of 0.15-ish combined with a severalfold increase in cross-sectional area, while your weight increases from 66lbs to almost 1700lbs.

It's hard to say that Aptera wasn't going for as extreme as you can get while still meeting those basic consumer requirements; it's just that those basic consumer requirements really take a huge hit on your energy consumption. The 2e is still 2-3 times more efficient than a Prius, but it's nothing like the extreme demonstration vehicles out there such as Pac Car II.

Could you do better than the Aptera? Probably. You could go for tandem seating to reduce cross sectional area, at the expense of cargo space and some consumer acceptability. You could build out of honeycomb foam core carbon fiber rather than the equivalent using fiberglass (which is 50% denser), but that'd raise your sale price by a lot. You could skip the electric drivetrain and save a hundred pounds or two, but then you're worsening your environmental impact in other ways. So, I'm not really sure you'd want to take the concept any further than Aptera has. A lot of people already think they've gone too far... ... I should add, myself definitely *not* included; I'm on their waiting list!

Re:Going fast is easy. (1)

Dunbal (464142) | more than 5 years ago | (#27490831)

So one day someone will come up with a hybrid solar/electric vehicle, that uses stored energy to accelerate, and solar power to cruise/extend the range?

Why are Americans always trying to use up the Sun? (0)

Anonymous Coward | more than 5 years ago | (#27490331)

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.

Obligatory (1)

sexconker (1179573) | more than 5 years ago | (#27490805)

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!)

Re:Obligatory (1)

Culture20 (968837) | more than 5 years ago | (#27491829)

(Solar cars are still electric, it applies dammit!)

Obviously you've never seen a steam powered solar focusing array on wheels. Not everything is photovoltaics.

Re:Obligatory (1)

Soul-Burn666 (574119) | more than 5 years ago | (#27492113)

(Solar cars are still electric, it applies dammit!)

Obviously you've never seen a steam powered solar focusing array on wheels. Not everything is photovoltaics.

He hasn't, but have you?

Re:Obligatory (1)

Rei (128717) | more than 5 years ago | (#27492725)

That's [teslamotors.com] very [wrightspeed.com] insightful [lightningc...pany.co.uk] of [venturivolage.fr] you [hybridcars.com] , you [shelbysupercars.com] know [autobloggreen.com] .

Re:Obligatory (1)

sexconker (1179573) | more than 5 years ago | (#27492911)

It's a Simpsons quote.

Unimpressive (1)

Paranoid times (1223056) | more than 5 years ago | (#27490859)

I don't know, one could power a small country with the same power needed to run the Spaceballs hair dryer.

So, I could put a lawmower engine in it... (1)

tjstork (137384) | more than 5 years ago | (#27491009)

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.

Re:So, I could put a lawmower engine in it... (1)

averner (1341263) | more than 5 years ago | (#27491901)

The heat and exhaust generated from the lawnmower engine would make it difficult to fit into similar dimensions.

Re:So, I could put a lawmower engine in it... (1)

tjstork (137384) | more than 5 years ago | (#27494313)

The heat and exhaust generated from the lawnmower engine would make it difficult to fit into similar dimensions

I was thinking more horsepower-wise than actual lawnmowerness. I get the impression that the run of the mill lawnmower engine lacks a lot of the fuel efficiency technologies of their larger cousins.

What They Don't Tell You Is That It Only Does 40 (1)

CyberSlammer (1459173) | more than 5 years ago | (#27491057)

It gets near 60 once the F-250 rear ends it and pushes it along.

88mph? (1)

davidwr (791652) | more than 5 years ago | (#27491161)

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.

Let's do the math (2, Informative)

Ancient_Hacker (751168) | more than 5 years ago | (#27491791)

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.

Re:Let's do the math (2, Informative)

Rei (128717) | more than 5 years ago | (#27492769)

A hair dryer draws around 750 watts

That's one weak hairdryer.

it's going to slow down to 70.7%

If there were no batteries to average out the ups and downs.

Re:Let's do the math (1)

Ancient_Hacker (751168) | more than 5 years ago | (#27495047)

A hair dryer draws around 750 watts

>That's one weak hairdryer.

Your typical bathroom outlet starts getting hot at anything over ten amps, 1200 watts, which is not even twice as much. And since the hair-dryer was a simile to begin with....

it's going to slow down to 70.7%

>If there were no batteries to average out the ups and downs.

Batteries have to be carried uphill too, so you gain some and you lose some.

Re:Let's do the math (1)

Rei (128717) | more than 5 years ago | (#27495213)

A hair dryer draws around 750 watts

You know, you could have at least bothered to google "hair dryer" and "watts" [google.com] . The first link you'll find is reviews for hair dryers in the 1200 to 1800 range. My hair dryer at home in my downstairs bathroom is 1600W.

Batteries have to be carried uphill too, so you gain some and you lose some.

That doesn't change the fact that they average out demand differences. They're a *net loss*, but they can eliminate the changes in speed that would otherwise occur on slopes.

Re:Let's do the math (1)

Ancient_Hacker (751168) | more than 5 years ago | (#27496953)

There is no point in arguing about wattage of your hair dryer. We're talking about the power available on a solar vehicle, not the maximum power of some rather poorly chosen simile.

The real point is that a solar powered vehicle is only going to have one or two horsepower available at best on a very sunny day-- fine for a bicycle or rickshaw but not so good for the kind of vehicle most of us need.

Re:Let's do the math (1)

keithpreston (865880) | more than 5 years ago | (#27493545)

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.

Sweet! I live in Kansas. I got to get me one of these!

Re:Let's do the math (1)

daybot (911557) | more than 5 years ago | (#27495469)

A 3% slope is going to slow it to a crawl. Not too good anyplace but Kansas.

I live in Cambridge, where this thing was built, and I can tell you that for us this restriction is not a problem - the whole city is totally flat. That's why 25% of the population cycles to work. The thing that doesn't make sense is that it is a solar powered vehicle - not much sun here. Rain powered, or if you could feed it foreign language students - that would be ideal!

I'm Icarus, you insensitive clod! (0, Troll)

Hognoxious (631665) | more than 5 years ago | (#27491997)

What they don't mention: you have to get so close to the sun that the tyres melts.

Crash Test? (1)

rsoohoo (1278822) | more than 5 years ago | (#27493857)

That car won't be passing any crash tests soon. I still appreciate it as a fine piece of engineering, though.
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