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Aussie Team Smashes Land Speed Record For Solar-Powered Cars
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!"
that it was only making about one point twenty one kilowatts.
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
See also http://en.wikipedia.org/wiki/Nuna_5 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.
Therefore, by the (faulty) logic you're using, you're just a cow with a keyboard - osu-neko (2604)
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.
http://michaelsmith.id.au
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.
Please help metamoderate.
which everyone who visits here assures me is so much brighter than their part of the world.
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.
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.
Welcome to Planet Earth, where everyone uses the metric system - except for Americans.
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.
Yes that is standard practice.
http://michaelsmith.id.au
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.
At the time the movie was made, the giga prefix wasn't in popular use except in certain scientific fields, and scientists disagreed whether it should be pronounced with a hard g or a j-sound. Jiggawatt was a perfectly correct pronunciation which simply went out of fashion.
Finally! A year of moderation! Ready for 2019?
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.
88 km/hr is slower than the one-hour standing start record for human powered 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.
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
This was performed by The University of New South Wales, which is in Australia.
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