Donation Spotlight: Xenith
Donor: Nathan Hall-Snyder
What happens when you put some of the best engineering minds at Stanford in a room and tell them to design the most efficient car possible? Xenith happens. The Standford Solar Car Project is one of the countries top solar car teams and consistently competes with the best in the world. The goal of the project is to design, develop and eventually run the car in a 2000-mile endurance race across the Australian outback powered by nothing but the sun and kinetic energy recovery. The cars each take years to develop and implement the latest in solar, battery and mechanical components to create a light-weight car with a small aerodynamic footprint and super-efficient motor. This particular car has a 5-kWh battery pack with an output of 1200 Watts, with stored energy alone it has a range of 200 miles but with solar charging, wind assistance, and kinetic energy recovery factored in, its range is essentially limitless. It weighs in at just 379 lbs. (without a driver) and can reach a respectable 90 mph, but don’t expect much trunk space or luxury from Xenith as it is designed solely for efficiency.
Each year dozens of teams set off from Darwin, Australia and make their way to Adelaide, Australia - a journey of nearly 2000 miles. The road is barren, sometimes going hundreds of miles with no signs of civilization. Traveling by any other means, your greatest enemy would be the relentless sunshine constantly beating down, but for these cars, the sunshine is their saving grace. Each team is required to be entirely self-sufficient. Every day teams drive as far as they can, stopping at 5 pm sharp and setting up camp wherever they may be. Teams have to carefully balance speed and efficiency, a creative challenge as much as an engineering one.
The Stanford team used every trick in the book for Xenith, using solar and kinetic energy recovery to keep the car moving at maximum speed while maintaining enough power to keep the wheels turning. This requires constant adjustment of speed and attack angle. To do this, Xenith is controlled by a unique rear wheel steering system allowing the driver to fix the wheel at an angle opposite crosswinds, effectively sailing the car on the road while simultaneously recharging the battery and running the electric motors. At peak speed, the journey would take Xenith just shy of 21 hours but weather conditions can stretch the journey out much longer. It is a test of will as well, but students jump at the opportunity for this “adventure of a lifetime.”
Building the car is a learning opportunity for the undergraduate students as well, with many going on to work for top engineering companies including Tesla. Xenith is a testament to what electric cars are capable of, foreshadowing the future of the auto industry. Someday efficiency may evolve to keep family sedans running on nothing but the sun, but for now, you’ll just have to squeeze into Xenith if you want your car to run on the sun alone.
By: Jeremy Malcolm