Think of a car that covers more than 2,000km in a single hydrogen tank. Wouldn't that be a welcome change in a world grappling with the challenges of climate change and the need for sustainable energy solutions?
Pushing the boundaries of efficient energy technologies is the aim that is driving the Eco-Runner Team Delft, which aims to set a new world record for a hydrogen vehicle that will travel the farthest distance without refuelling. The initiative recently released its latest iteration for this year, Eco-Runner XII.
A team of 23 students from the Delft University of Technology in the Netherlands is behind the project. Each year, they try to improve the design and aerodynamics of their small hydrogen-powered city car to make the most recent model surpass previous records.
The team has come a long way since its prototype, Eco-Runner I, which participated in the Shell Eco-marathon, a worldwide energy efficiency competition in 2005. The car then achieved an efficiency figure of 346m/L (557km/L) of hydrogen in the top-five entries.
In 2022, its Eco-Runner XI attained a figure of 2110 m/L (3396km/L), also setting the world record for the longest distance travelled in a hydrogen vehicle by driving non-stop for 36 hours and covering 1,196km.
The team is confident that with the Eco-Runner XII, it has now improved upon the design to ensure it becomes the "world's most efficient, hydrogen-powered city car", according to its web page.
Focus on reducing weight and energy loss
One of the critical goals of the team when developing the Eco XII was to decrease weight as much as possible. The consumption of energy while driving is directly linked to the mass of the car is lower.
"The Body department focussed on creating an aeroshell and a load-carrying structure that was as lightweight as possible without breaking," said a blog post. The use of carbon fibre in place of typically produced steel components was the key to reducing the car's weight. Suspension beams or the steering system's pushrods are a few examples that helped shed the car's overall mass.
Limiting internal energy losses is another aspect of efficiency. "These losses include rolling resistance, air drag, but also the losses that occur when converting hydrogen to electricity or converting electricity to kinetical energy (movement) in the electrical motor."
The team created a new, highly efficient electric motor specifically tailored to reduce these energy losses. Engineers also improved the powertrain system with a brand-new fuel cell that addresses the requirements.
The requirements have led to a unique bubble-car shape which allows it to keep aerodynamic drag and weight as low as possible. The car's kerb weight stands at 67 kilograms, and has a top speed of 25km/h.
Aiming to take the game forward in energy efficiency
The segment has seen intense competition after Eco-Runner XI did 1,196km. In October 2021, Toyota could cover 1,360km without refuelling, surpassing the previous team's performance.
Another competitor emerged in 2022 under the moniker ARM Engineering. They drove for 40 hours straight and managed to cover 2,055.68km with their automobile on one hydrogen tank – a significant step forward in illustrating the potential of fuel cell technology.
The team hopes that improvements will help it regain the world record by covering a distance of more than 2,055km in a single run. The record attempt will be made in June.