Competing to Make the World's Most Efficient Solar Car

Watch this: Creating the World's Most Efficient Solar Electric Car

03:36

This solar-powered car's narrow streamlined shape and lightweight carbon fiber exterior helped it take home the top prize at the 2023 Bridgestone World Solar Challenge: 

Every two years, engineering teams from around the world bring their solar-powered EV creations together to pit them head-to-head to push the limits of technology and help discover the optimal design for a solar-powered vehicle.

This year's competition took place in the Australian outback. Competing solar vehicles were allowed 5kW hours of stored energy, that's about 10% of what's needed for the roughly 1,860 mile distance. The remaining 90% had to come only from the sun or from the kinetic energy of the vehicle itself: like how some cars use the energy from the brakes to recharge the battery.

Vehicles in the World Solar Challenge are divided into three classes: Challenger, Cruiser and Adventure. 

Challenger class vehicles travel the full 3,000 kilometers, stopping every day at 5 p.m. and making camp wherever they are. Cruiser class vehicles cover the same distance in 1,000-kilometer (or about 620-mile) stages. They have to hit specific time targets and seat at least two people, and they're ultimately given a "practicality" score, based on things like design, environmental impact, ease of use, passenger comfort, controls, features, style and more. Adventure class is where cars made in previous competitions can come back for another round. 

This year, 31 solar-powered cars left the starting line: 23 in the Challenger class and eight in the Cruiser class. Only 12 reached the finish line. First place in the Challenger class was Belgium's Innoptus Infinite, with an average overall speed of about 55 miles per hour. The addition of a retractable fin at the top allowed the car to sail with the wind, rather than fight against it, and may have helped give the Innoptus Solar Team the edge during reportedly high gusts. Team Twente from the Netherlands came in second place with the Red X, its first monohull designed car, and the Brunel Solar Team, also from the Netherlands, came in third with the Nuna 12, featuring an asymmetrical two-hull design and an AI designed exterior graphic.

The Sunswift 7, which weighs about one-fourth what a Tesla does, took the top prize in the Cruiser category, and broke a Guinness World Record for "Fastest EV over 1000km on a single charge." It was followed by UMN's vehicle Gaia in second place and Estonia's Solaride 2 in third.

Pitting these vehicles against one another in competition helps test and develop new battery types, solar cells and aerodynamic designs, some of which have been provided by major companies and some of which have been made by student engineers. It also provides a training ground for student engineers to test and refine their products, and to flex their skills.

As to whether solar-powered cars will become mainstream, that's a much bigger question. And we'll have to see how the solar cars leading the charge, like the Lightyear 0, the Sono Sion and the Aptera, deliver on their promised efficiency and convenience, and how they're received by drivers.

To see footage of the World Solar Challenge vehicles in action, check out the video in this article.