Building cars from plants sounds immediately implausible, a concept best left for science-fiction authors rather than automotive critics.
And yet here we are. This is a question we’re asking, and, you know what? The answer might just be yes.
Of course, it’s a qualified yes – don’t expect the next Nissan Leaf to live up to its name quite as literally as you might hope. That said, Dutch academics from Eindhoven University of Technology have just succeeded in building the world’s first plant-based vehicle.
As explained by Quinten Oostvogel, team manager of the TU/ecomotive group: “We wanted to look at bio-based options to build a chassis and considered the plant flax. Flax fibres are very tough, and the flower is very popular in regions like Canada and Russia. This makes it ideal for making strong composites.”
22 students took part in designing, engineering, and building the car, and they did it from the groun up. “We built the flax fibres ourselves,” said one participant. “We first dried thousands of plants in a field in the summer.”
The plants were heated to separate the fibres, which were woven into 100-meter rolls and then dried. Pressed together in an oven, they created strong sheets of flax fibre. Those sheets weren’t strong enough to endure the stresses and strains faced by a vehicle chassis, so a honeycomb PLA (polylactic acid) structure was placed between sheets.
The finished chassis was 80% flax fibre, tipping the scales at just 70 kg. For the sake of comparison, the average UK man weighs 83.6kg, so this chassis probably weighs less than you do. A plant-based powertrain is still beyond our grasp, so students used an electric drivetrain with two motors and a modular lithium-ion battery.
The finished car was named Lina after the Greek goddess of weaving. It came in at 310kg.
As explained by Oostvogel: “Car makers opt for lightweight materials such as aluminium and carbon fibre to create lighter, more efficient cars. The processing of these materials, however, requires five to six times more energy than steel.”
Flax fibre doesn’t require such energy, and it’s obviously far light than any of these materials. As a final string to its bow, it can be easily recycled, and, reinforced with the honeycomb structure, it has the same structural strength as a fibreglass chassis.
The flax-based vehicle may not yet have hit dealerships, but it might just be the wave of the future.