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Transportation Australia Power

Aussie Team Smashes Land Speed Record For Solar-Powered Cars 82

Posted by Soulskill from the with-authority dept.
snowdon writes "A record which has stood since 1987, set by General Motors, has been broken (YouTube video) by a university team. The land speed record for a solar powered car was 78km/h, and now stands at 88km/h despite the cloudy conditions... If only Doc Brown had used the metric system!"
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Aussie Team Smashes Land Speed Record For Solar-Powered Cars More

Aussie Team Smashes Land Speed Record For Solar-Powered Cars

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  • Whats more amazing is... (Score:5, Funny)

    by noisyinstrument ( 1624451 ) on Sunday January 09, 2011 @02:12AM (#34812500) Homepage

    that it was only making about one point twenty one kilowatts.

  • Landspeed record for disabled cars? (Score:3, Interesting)

    by St.Creed ( 853824 ) on Sunday January 09, 2011 @02:25AM (#34812562)

    This seems rather low, and certainly not a record. Unless they compete in a "differently abled" class?

    The Nuna 2 solar powered car that won the World Solar Challenge in 2003 had the following stats for the race:
    Total race time: 31 hr 5 mins.
    Average speed: 97,02 Km/h
    Topspeed: 130 km/h
    Top speed they had during Adante tour in 2004: 145 km/h
    Link: http://www.esa.int/esaCP/SEMCCBZO4HD_Benefits_2.html [esa.int]

    See also http://en.wikipedia.org/wiki/Nuna_5 [wikipedia.org] for the stats of the Nuna 5.

    Theoretical max speed: 175 km/h

    Keep in mind that this was done by a (Dutch) university team as well.

    Considering the fact that the sunswift team wants to compete in the WSC as well - I think they either need to get up to 188 km/h, or throw in the towel. Or perhaps I'm missing something but I did RTA and nothing suggests they really set a new speedrecord, except their own propaganda.

    • Re:Landspeed record for disabled cars? (Score:5, Informative)

      by Nuno Sa ( 1095047 ) on Sunday January 09, 2011 @02:41AM (#34812630)

      The car in TFA didn't have a battery. The solar panels are connected directly to the drive train/motor(s).

      • The production model will use a beer battery [howstuffworks.com].

        If you want a few "travellers" for the trip though I'd recommend using something different to Fosters.

      • The car in TFA didn't have a battery. The solar panels are connected directly to the drive train/motor(s).

        Also from TFA (or associated news reports), the lack of battery was to raise, not lower, final speed.

        I also found the low speed pretty iffy given that in past races, racers have happily exceeded 120-130km/h. I'm assuming it was either an average over a long distance, or otherwise subject to criteria not mentioned to slow it down.

        • The available power that the wheel motor can use to accelerate is limited to what the array generated when the battery is removed. During the race, the car has both the power from the array and the battery.
      • Both vehicles have 25KG battery packs. Read the spec sheet. The difference is that they didn't use the batteries in the world speed record run.

        • And my bike has a set of training wheels. Which I remove whenever I don't wnat to carry the extra weight or enter competitions that require 2 wheel vehicles :-) So what?

    • Re:Landspeed record for disabled cars? (Score:5, Informative)

      by NoMaster ( 142776 ) on Sunday January 09, 2011 @02:41AM (#34812632) Homepage Journal

      The difference is the WSC cars are allowed to use a battery - the rules for the Guinness World Record specify solar power only.

      In the 2009 WSC the UNSW car reached 103km/h with a LiPol battery, but that was removed for this attempt to comply with the Guinness rules.

      • Re: (Score:1)

        by Seumas ( 6865 )

        Which, of course, is only useful for setting records, since you need a battery to keep you running when you're not directly under the midday sun. Then they'll only need to increase the speed by at least another 50%. And then maintain that when the full weight of a real car. And its passengers. And cargo. And then figure out some way to keep the solar receivers from being damaged by things like regular road debris (rocks, etc) and hail. Or from just losing their efficiency rather quickly over time.

        Give us an

        • Did you even look at the video? You wont be taking their car to the local supermarket at all.

          Getting a car going that fast when its batteries are flat is quite a feat. Imagine a Telsa that could do that. Useful no?

          • You wouldn't take a Formula 1 car to the supermarket either.
          • "Did you even look at the video? You wont be taking their car to the local supermarket at all."

            I don't know, they've made a lot of progress in only 15 years, going from 66 km/h in 1987 to 102 in 2005. [wikipedia.org] They got so fast that the support vehicles could not keep up without breaking the speed limit, [wikipedia.org] so new rules were put in place that forced teams to reduce the number of solar panels, require a steering wheel and even add safety equipment.

            At the rate things are going someday they might require a car with
            • But what was their speed at the time they weren't running on batteries? And how do you know for sure that there wasn't any battery power left?

            • No, the record is completely valid.

              If the other guys could break it, then they just have to remove their batteries and do two laps. They could break it again right now if they wanted.

              Because they averaged that is irrelevant. Thats not what this world record is for so it doesnt count.

    • Nuna was using its battery (Score:4, Informative)

      by SuperBanana ( 662181 ) on Sunday January 09, 2011 @03:02AM (#34812714)
      Both vehicles have about 25kG of batteries. The difference: Sunswift 4 was operating only off solar power, whereas Nuna was in a race where batteries were not only allowed, but required (the race was over several days.) Nuna had both solar and battery power for acceleration.
    • Nuna 5 used 6 sq. meters of Gallium Arsenide cells, which are about 10x more expensive than Silicon cells, which Sunswift IV used. In the upcoming 2011 WSC, GaAs cars are limited to only 3 sq. meters of array surface area.

  • Surely powertrains can do better than this ?

    can it not use a battery ?

    this is not much use unless there is a context...

    I mean if the driver weighs little surely they can achieve a higher speed.... so what are the rules ??

    regards

    John Jones

    • I think the issue is more the power/drag ratio of the photovoltaic cells.

    • Re:no one was intrested ? (Score:5, Informative)

      by Ronin441 ( 89631 ) on Sunday January 09, 2011 @03:37AM (#34812842) Homepage

      I can tell you the World Solar Challenge rules. (The SunSwift car depicted looks like it follows WSC Challenge class rules.) There are safety requirements for roll cage, braking, steering, wiring, circuit breakers. The driver's eye-line must be at least 70cm above the road. There's a maximum angle the driver is allowed to lay back at. There's a max of 6 square meters of solar cells. The battery is a max of 5kW.h. (This is a trivial amount of energy compared to the energy budget over the whole challenge, but is tactically useful for hill climbing, clouds, etc.)

      It looks like the only change they made for this Guinness challenge was to remove the battery pack.

      Yes, it looks like the 2003, 2005, 2009 WSC challenge winners (Nuna, Nuna, Tokai) could have knocked this record over, just by removing the battery pack and getting Guinness certification. Doing some rough maths, UNSW's pace is still pretty competitive: the speeds you see listed for WSC course competition do not figure in the time the cars spent charging their batteries each dawn and dusk, after racing ends at 5pm for the day and before it begins at 8am the next day.

      • Re: (Score:1)

        by Anonymous Coward

        Nuna, Tokai, and most of the other top cars from the last decade use GaAs solar cells. The Guinness record requires the use of silicon cells.

  • The article do not mention that car is only allowed to run by direct solar power.
    no batteries are allowed in this competition.
    http://en.wikipedia.org/wiki/Sunswift

    • The article do not mention that car is only allowed to run by direct solar power.

      They say:

      We smashed the Guinness World Record for fastest Solar-Powered vehicle by over 10 kmh.

      It doesn't say Battery powered or Petrol powered.

  • Cheating by using the Australian sun.. (Score:2, Insightful)

    by Anonymous Coward

    which everyone who visits here assures me is so much brighter than their part of the world.

    • Re:Cheating by using the Australian sun.. (Score:5, Funny)

      by MichaelSmith ( 789609 ) on Sunday January 09, 2011 @03:20AM (#34812768) Homepage Journal

      which everyone who visits here assures me is so much brighter than their part of the world.

      Thanks to ozone depletion we get more energy out of the sun.

      Seriously its the dry air. It absorbs less solar radiation so more hits the ground.

    • Re:Cheating by using the Australian sun.. (Score:5, Interesting)

      by Cimexus ( 1355033 ) on Sunday January 09, 2011 @07:47AM (#34813722)

      There's quite a bit of truth to what they are telling you. As MichaelSmith alluded to, it's mostly because of the lack of airborne moisture, particulates and pollution cf. the comparatively wetter, more land-covered, more populated northern hemisphere.

      In fact as an Australian that went overseas to the US and Europe for the first time as a 20 year old, it's one of the first things I noticed when I stepped off the plane. The sky is often a light, hazy blue, close to ~white~ near the horizon, even on a cloudless day. Put simply, it's the greater humidity in your atmosphere (with some contribution from both man-made pollution, and natural particulates such as pollen etc). OTOH as soon as you are >50km away from the coast in Australia, a sunny sky will be a deep, deep blue, with no discernable difference in colour between 'straight up' and 'at the horizon'. Not to say you can't get days like that elsewhere (desert regions would be like this world-wide), but this is the norm over most of Australia. Where I live (which is in the inland of Australia), I have never seen that 'white haze' that is common in the northern hemisphere sky.

      Of course that viciously blue sky, although nice for solar power and photography, is a curse in many ways. Low average humidity makes us the driest inhabited continent, and we also have the highest UV irradiation on earth (and the highest rates of skin cancer as a consequence). The UV index used worldwide was obviously developed in the northern hemisphere since the highest category 'Extreme' starts at 11+ (and is supposed to represent the 'top few days' in a year). The scale is kinda useless in Australia since EVERY day is 'Extreme' (our normal summertime UV here is typically in the 13 to 15 range, and I've seen higher): http://en.wikipedia.org/wiki/Ultraviolet_index [wikipedia.org]

      • Re: (Score:1)

        by Anonymous Coward

        It would have been a bigger cheat to run in Western Australia at that time rather than Nowra. Hot, clear, clear, hot. If they got 88kmh under cloud in Nowra I would have a dollar that they would have got 100kmh here as it has been bright, clear sunshine even on the cooler days.

  • The "wing" portion of the car that has the solar panels appears to replicate the shape of an aircraft wing - why? The lifting force of the airfoil, while helpful for rolling friction, results in additional drag. Considering how negligible the rolling friction is I do not see this as being helpful. I would think that a thinner wing that cuts cleanly through the air without any resulting lift would do better. Of course the one photo of the car that I saw could have simply given me the wrong impression reg

    • Maybe most of the cells are pointing into the sun. The panel can't be flat without losing energy collection efficiency.

      • I could be wrong, but usually the speed tests are done in both directions with the end speed being the average of the two values. This prevents people from taking advantage of things such as wind and/or angle to the sun.

    • Re:So why the airfoil shape? (Score:4, Informative)

      by snowdon ( 80398 ) on Sunday January 09, 2011 @04:07AM (#34812962) Homepage Journal

      It would be awesome if we could have made it thinner -- the wing is there as the lowest-drag shape that we can put around the other components in the car -- suspension, steering, driver, etc. Its designed to be a lifting body because of the ground effect which would otherwise result in a negative lift. The cambered wing counters the negative lift generated by the ground effect.

    • Re: (Score:1)

      by cjanota ( 936004 )
      Being near a ground plane can generate down-force. The wing might be shaped to generate a little lift to counteract that. Though it seems too high off of the ground for the ground plane to come into play much.

    • Re: (Score:1)

      by feufeu ( 1109929 )
      From looking at the front page picture of their website i'd say that it looks like an airfoil with a slight positive camber (creates some lift) but negative angle of attack (nose farther down as the trailing edge). That should more or less create zero lift but was probably engineered like this for less drag given the ground effect of the road underneath (last part is a wild guess).

  • Seriously? (Score:2, Insightful)

    by CAIMLAS ( 41445 )

    This is wholly - as in, absolutely, completely - unimpressive. If I could be de-impressed, I would be.

    It's been over 20 years since the 'original' record was set, and it's only now being broken? What the fuck have we been spending gobs of "government" money on green energy for, if this record is only now being broken?

    And it's not even "the" record. It's the "electric" vehicle record! How is that even significant, when electric vehicles are trying to compete against traditional ICE vehicles? It's like being

    • Take a look at PV cell efficiency 1990 to 2010 [wikipedia.org]. Gains are being made but they are not spectacular. I don't think the best cells are appropriate for mounting on a vehicle.

      And if you want to compare electric vs ICE vehicles battery technology is the issue.

    • Re: (Score:1)

      by rtb61 ( 674572 )

      Me thinks you have never heard of things like, greed and patents. The two things most holding up the development of better solar panels and better batteries. If governments were really serious are pollution, they would do what they did during wars, suspend patents in the affected technologies and directly sponsor development, after better technology has been developed (by consolidating different technological developments) they can sort out corporate greed.

      Even worse money is being spent on blocking deve

      • Companies the world over are trying to build better and cheaper solar panels. Many of them have received very significant government investment. Take a look at Emcore, Spectrolab, Sunpower, First Solar, Solyndra, Evergreen Solar, REC, etc etc. The list extends beyond the eye can see.

        You do have a point, however. Our current patent and copyright system is an exercise in absurdity and needs to be fixed - somehow. But those systems are not a problem for the solar industry yet. The field is growing far too quic

        • I don't know about carburetors, specifically, but it's certainly true that car companies have been building cars that are less efficient (in terms of mpg) than they could have been, for a long time.

          Just to be clear: I am not stipulating the existence of any conspiracies here, just observing a fact.

          • people want 7L V8 pole-magnets, not less sexy 1.2L 4cyl things with room for passengers and luggage but no boat or caravan.

            efficiency went right up in the late 70s as fuel got more expensive. God knows why they're dragging their feet on efficiency now, but bear in mind it's only really american cars that are this crap.

    • Re:Seriously? (Score:5, Insightful)

      by FrootLoops ( 1817694 ) on Sunday January 09, 2011 @08:03AM (#34813780)
      The sun only produces so much energy per unit area on earth. As I understand it, this vehicle uses solar power directly (without storage). Really, you could probably only hope for another order of magnitude or so before reaching the theoretical limit of perfectly efficient solar energy to kinetic energy transfer, and that upper limit is generous.

      My point is solar power usage in situations like this has a definite upper limit of efficiency, which we're not *that* far away from.
      • I should also mention friction and air resistance should be at least approximately proportional to velocity, and work is force times distance, so in a given distance solar energy has to overcome work proportional to velocity trying to slow you down. At higher speeds you travel the same distance more quickly, so solar power needs to overcome the power of friction and air resistance ~quadratically related to velocity. That is, it gets much harder to go a little faster as speeds increase.

        • Re: (Score:2, Informative)

          by Anonymous Coward

          Power is proportional to velocity cubed for air resistance actually (and velocity for rolling resistance). On 200 watts the car will go 50km/h (we did this on the day when the sun went away), at the 1100 we got we hit 88, over 5 times the power for less than double the speed. Likewise between 88 and 100 you get ~ 1.4x as much aero drag.

    • It's not as bleak as you think. The GM record was set with 15 square meters of solar panels, and the UNSW team broke it with 6 square meters of panels. Both are using commercial grade rooftop cells that you can buy right now.

  • It's too bad they didn't have a water powered car... it would be going like crazy.. if not for all the flooding.

  • Still slower than humans (Score:3)

    by tcgroat ( 666085 ) on Sunday January 09, 2011 @03:01PM (#34816594)
    88 km/hr is slower than the one-hour standing start record for human powered [ihpva.org] streamlined bikes (90.6 km/hr for a single rider). I suppose that's because the large surfaces needed for the solar cells add to the frontal area and drag for the electric vehicle.

  • Fastest Indian (Score:3)

    by shermo ( 1284310 ) on Sunday January 09, 2011 @03:42PM (#34816946)

    To whomever tagged this 'fastestindian'. The moniker refers to Burt Munro who was a New Zealander.

    http://en.wikipedia.org/wiki/The_World's_Fastest_Indian [wikipedia.org]

    This was performed by The University of New South Wales, which is in Australia.

  • There is still land in Australia? ;-)
  • I love solar cars. I hope that one day they will replace present cars. That day will come,I'm sure!
  • I don't think the line "141.6-ish kilometers per hour!" rolls off the tongue nearly as well.

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