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Dutch space-age solar racing car ready for the start!
17 October 2003
On Sunday 19 October at 8.00 am local time, the solar-powered Dutch racing car, Nuna II, will start the 3,000 km race across the Australian outback. Nuna II is the successor to Nuna, which won this race in 2001 thanks to its use of European space technology.
“Nuna II is in perfect condition and has been extensively tested over the last few weeks,“ Koen Koster from the Dutch team enthusiastically reported. “Before we could make the car race-ready, we had to first obtain a ‘road permit’. This certificate of roadworthiness was needed because the race is going to be held on a public highway. The ‘road authority’ first carried out visual checks and subjected Nuna II to a braking test. After the car had passed the test with flying colours, we could carry out further tests on the section of highway that was designated for us to use”.
“This section of highway, the ‘Arnhem Highway’, starts just outside of Darwin and finishes in the middle of the Kakadu National Park. However, before we began, we still wanted to subject Nuna II to the most extreme tests on the closed ‘Hidden Valley’ race circuit. The main aim of this was to conduct a speed test and Nuna II reached no less than 105 km/h on the straight section and had to handle the bend with full braking power. While other cars would generate a lot of loud noise, Nuna II was a delight to the ears: with its now familiar whoosh it flashed across the circuit. The cruise control was also adjusted: a precise job because cruise control ensures that the speed attained during the race is exactly that prescribed by our strategist Eric Trottemant.
| | Nuna-II in the 7th World Solar Challenge | |
”The racing drivers on test day, Mark Olsthorn and Sten Swanebreg, were also tested to the limit, the temperature was extremely high and was therefore ideal for testing the cockpit. Fortunately the ventilation worked and the special driver cooling suit was also a success. As soon as Nuna II came to a stop, the cockpit became a glowing oven within a second. The life of a racing driver is certainly not a bed of roses.”
Advised by an astronaut
This enthusiastic report comes from one of the twelve members of the Nuna team who will take part in the race with Nuna II. Will Nuna II repeat the feat that Nuna made on its debut in 2001 and win again?
The racing team, which is advised by former ESA astronaut, Wubbo Ockels, is determined to make an attempt on the established world record held by Nuna. Nuna finished the race in 32 hours and 39 minutes with an average speed of 91.81 km/h. The Nuna II team will try to finish the race within 30 hours with an average speed of 100 km/h. Everything will depend of course on the conditions at the time. A collision with a crossing wallaby or kangaroo and the race will very likely be called off. That is why Nuna II will be preceded by a ‘scout’ car. The ‘scout’ car will drive to the finish 100 metres in front of the racing car to check that there are no obstacles on the road and to warn oncoming cars.
| | Nuna II team | |
Space travel ‘high tech’
The car does not just depend on the materials from which it is constructed. The 5 metre long and 1.8 metre wide vehicle is provided with the very latest space travel ‘high tech’.
The surface of the car is equipped with ‘triple junction’ solar cells comprising of three layers. In this type of solar cell, sunlight passing through the first top layer that would not otherwise be utilised, is absorbed by the second layer and even by the third layer. These solar cells are still so new that ESA has only been using them in space since the launch of SMART-1 on 28 September. SMART-1 is testing, among other things, a solar energy powered ion engine.
The race car has an optimised energy output from the solar cells because of its Maximum Power Point Trackers (MPPTs). Although shade makes some solar cells less effective, the MPPTs keep the total energy from the solar cells high and constant. MPPTs have already been used in satellites for years. Satellites must obtain the maximum possible output from solar panels when they are in the shade. The European comet explorer Rosetta which will, in February 2004, make its way to comet Churyumov-Gerasimenko, is also fitted with MPPTs.
The accumulator batteries also come from space travel technology. There are 46 large lithium ion cells connected in series, and the solar racing car produces 5 kWh of energy. The moon satellite SMART-1 mentioned above has exactly the same lithium ion cells on board.
Last but not least, there is the car itself, which is entirely constructed from lightweight carbon-fibre with its upper side and wheel mudguards strengthened with aramide. The extremely strong aramide (better known by the trade names ‘Twaron’ from the Dutch company Ten Cate Advanced Composites, or ‘Kevlar’ from DuPont) is also used in space suits and for the protection of astronauts in some parts of the International Space Station.”
Winning strategy
“Are they going to win again? I give the Dutch team a very good chance,” says Wubbo Ockels, who made a space flight in 1985 and is now a professor at the TU in Delft. “I’ve had experience using the same type of ‘electricity’ with the last Nuna team and hopefully as we did two years ago, we can again put forward just such a winning strategy.”
"Anyway, this is such a fantastic project to be involved in! It is the combination of young people and technology that really appeals to me. Furthermore, it is of course a superb example of what is possible with solar energy and space travel technology."
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