Nuna7 and DSM: partners in world’s largest solar vehicle event
Durable energy and innovative technology
DSM is the innovation partner of the Nuon Solar Team that will compete in the 12th edition of the World Solar Challenge in October 2013. This solar-powered car race is held every two years, covering 3000 km through the Australian outback, from Darwin to Adelaide.
The 2013 edition of the solar race will bring new challenges, as for driver safety reasons new race regulations require significant changes in car design. These include the addition of a fourth wheel for improving stability and a larger driver’s canopy, requiring a full remodelling of the vehicle and a complete change of the construction.
In the previous race, in 2011, the Nuon Solar Team from Delft University of Technology (TU Delft, Netherlands) reached the finish line in only 5 days. After a head-to-head race with the Tokai Challenger from Japan, the Nuna6 ended up taking 2nd place – bringing its extraordinary track record to four wins and two second places.
This year, the World Solar Challenge will welcome 47 teams from 26 countries to take part in the world’s largest solar vehicle event. The Nuon Solar Team is ready to take on the challenge, and with the support of DSM is using state-of-the-art chemistry and technology for obtaining the best results.
Performing in a tough environment
In the World Solar Challenge the cars must drive the 3000 km in the shortest time possible. Only by using the available energy as efficiently as possible, will they reach the finish line ahead of the other participants. This means that achieving superior aerodynamics and low vehicle weight have to go hand in hand with the use of efficient solar cells and reliable electrical systems.
Temperatures in the Australian outback can reach extremes, and will be a challenge both for the driver and the car itself. Consequently, the Nuna7 car needs to have great dimensional stability at elevated temperatures. Additionally, the construction must be built in a smart way to have the best balance between weight and performance, while providing the driver with optimum safety protection in the (unlikely) event of a crash.
Six months ago the Nuon Solar Team from TU Delft and innovation partner DSM set out to develop and construct the best Nuna ever with the new design requirements as a starting point. DSM provided the resins and application technology used in building the framework of the car. The Nuna7 was manufactured using DSM's innovative and sustainable Styrene-free Daron® resins, optimized for use with the newest Textreme® Carbon fiber in a vacuum bagging process. The result is a superb vehicle that combines light weight, great aerodynamics, and dimensional stability at elevated temperatures.
In addition, several important components of the lighting and power systems were made using DSM Somos® stereolithography materials for rapid prototyping technology. These components have perfectly been integrated into the car's surface, contributing to optimal aerodynamics. DSM has also provided the TU Delft team with prototyping expertise, improving efficiency during the design and construction phases.
DSM, sustainability and the Nuna7
DSM’s involvement in the Nuna7 perfectly illustrates its commitment to both sustainability and innovation. By creating the right innovative environment, DSM, together with its partners, can produce new technologies delivering value added benefits to both people and planet.
The Nuna7 has been made with a new generation of DSM's styrene-free Daron resins. Because of their close-to-zero smell and solvent emissions, these materials are an environmentally preferred alternative to conventional styrene-based resin systems. This world-leading resins technology provided by DSM has resulted in obtaining three main improvements in comparison to the past: stiffer, stronger and lighter, resulting in a faster, safer and more energy efficient car.
Stiffness and structural integrity: the use of DSM’s Styrene-free Daron resins in combination with TeXtreme Ultra High Modulus carbon fibers in a vacuum bagging process has resulted in a 30% increase in composite material rigidity in comparison to the Nuna6. For this, the novel resin composition, excellent adhesion between resin and carbon fiber, and the elevated temperature resistance of the composite structure were instrumental.
This increase in composite material rigidity means the vehicle is 3 times stiffer as required to compensate for the additional torsion resulting from the extra fourth wheel. This is instrumental in obtaining the right aerodynamic design and minimized weight. This will also result in fewer vibrations, allowing the car to reach higher speeds and be more energy efficient.
Strength: the resin-fiber combination used in the Nuna7 makes the construction stronger compared to earlier versions. This is important for protecting the bottom of the car from rocks and debris, for car reliability and driver safety.
Weight: the rigidity of the innovative material provided by DSM allowed the design of the Nuna7 to be optimized for the new design requirements. This means reducing weight while improving the car’s performance.
Fast prototyping and part production
Somos materials by DSM were able to produce many part options quickly for the Nuon Solar Team by using stereolithography; a distinct and unique subset of additive manufacturing. The team used this technology not only for their prototypes, but also for some end-use applications such as inner wheel fairings and lighting components. The speed of the stereolithography process decreased development time by 50% and gave project designers the ability to make multiple iterations at the same time.
Through a combination of Somos TetraShell and Somos WaterShed XC 11122, designers were able to create durable, light-weight parts used for the final production vehicle. Somos TetraShell has been used to creat a honeycomb-like lattice within a part to decrease the weight (and amount of material), while maintaining the structural integrity of the part. The clarity of the Somos WaterShed XC 11122 gives parts the appearance of a thermoplastic, with the speed of stereolithography.
Partner for innovation
The Nuon Solar Team had to develop a brand new car design able to fulfill all the performance requirements in a short period of time. Therefore, the availability of the right materials and expertise was a prerequisite.
Through the excellent support of DSM in composite technology, resin chemistry, rapid prototyping, part design, and the hands-on support in manufacturing, a new Nuna7 could be developed at record speed. The result is clear: besides super-efficient electronics the Nuna7 has great aerodynamics, low weight and is resistant to the heat, enabling a fast race through great car performance.
The Nuon team comprises 16 ambitious and enthusiastic students from Delft University of Technology, all fully committed to showing the possibilities of the most efficient use of durable energy and innovative technology - to inspire shaping a sustainable future.
The 12th World Solar Challenge will take place between 6 and 13 October 2013. All teams will depart from Darwin aiming to be the first to cross the finishing line in Adelaide, 3000 km to the south. Among the contestants will be teams from all across the world, and the very latest in solar and composite technology and innovation will be on display once again.
We are convinced that through using DSM’s Somos stereolithography materials and Styrene-free Daron High Performance resins for the Nuna7, the Nuon Solar Team team is on its way to speeding across the finish line in pole position.