A smaller size
Nuna 9 was significantly smaller than its predecessors. Due to changes in race regulations, it was thirty percent smaller than its predecessor, Nuna 8.
Nuna 9 featured an integrated lift-and-lock system in the panel. This allowed the driver to lift the panel smoothly and lock it in a position perpendicular to the sun. They used a 3D printer and bicycle brake cables to create this system.
For the first time in eight years, the team used Gallium-Arsenide cells, which are also used in space technology. They had to choose between a larger panel with lower efficiency (Silicon) or a smaller panel with higher efficiency (Gallium-Arsenide). Ultimately, they opted for the latter, enabling the car to be six percent smaller.
Nuna 9 was conceived from a nightmare experienced by one of the aerodynamicists. Just before Christmas, he dreamt that the team's solar car lost the World Solar Challenge to a similar-looking car with a much smoother shape. The next day, the team analyzed this sleek design, and what did they find? The new shape, with a continuous front end without an overhanging nose, was significantly better! The team turned their dream car into reality.
Shortly before the race, a major challenge emerged. While the team members and the solar car had already arrived in Australia, a crucial component was missing: the battery was still in Amsterdam. This was because the airline had changed its rules for transporting batteries after seventeen flights experienced lithium-ion battery explosions. With only a month left until the race, the team's participation seemed uncertain. Emergency plans were made to build a new battery using components from Japan. They couldn't test their car for weeks. Eventually, the battery arrived just in time, allowing the team to start the race with their upgraded battery.
Nuna 9 was driven by three female drivers during the race. This was due to the new design of the solar car. It was smaller, and the driver's cabin was specifically tailored to them. Ultimately, the team won the race, leading the second-place team by hours, securing their seventh world championship in Australia!
1st place— Bridgestone World Solar Challenge 2015
3.3m x 1.5m x 0.98m
2.64 m2 Gallium Arsenide
20 kg Li-Ion