Lightyear validates world-record solar car aerodynamics

Solar car company Lightyear has taken its Lightyear One prototype to the testing track and has confirmed its incredibly low energy consumption, even on a cold and wintry day, thanks to the vehicle’s incredible aerodynamics and low energy usage.

Energy efficiency is top of the list for solar car design; the better the aerodynamics, the better any energy its integrated solar panels generates can be put to use.

After achieving a record-breaking simulated drag coefficient value of just 0.20 for its Lightyear One design in late 2019, Lightyear has now progressed to the point that it can start putting its design into action.

It is an important step in the road towards supplying 5,000 vehicles to car lease giant Leaseplan from 2024. Although the deal with Leaseplan is for the start-up’s Lightyear Two which has not yet been developed, the validation of its first Lightyear One model will lay the ground for this.

On-the-track energy consumption testing for the Lightyear One has included three key elements: rolling resistance of the tyres, the car’s internal heating system, and of course aerodynamics.

While the company did not confirm that it had achieved the 0.20 simulated drag coefficient it was seeking, it remains positive, describing its latets testing as being “on track”.

The company says that aerodynamics is by far the most important element to deal with, as huge amounts of energy can be needed as air resistance increases with vehicle speed.

This of course guides the Lightyear One’s extremely sleek design – but as the company notes, this has had to be balanced with the realities of passenger comfort. While solar cars used in the Bridgestone solar car racing challenge typically breeds cutting edge windswept designs, the Lightyear One must also be comfortable enough for day to day use.

Bridgestone, as it happens (and not coincidentally), is also Lightyear’s tyre partner, and it is the tyre giant’s testing track in Aprilla at which the Lightyear One’s testing is taking place.

Along with the aerodynamics testing, Lightyear is also testing the Lightyear One in “suboptimal” conditions: that is, on cold or cloudy days, or with extra luggage in the car, and so on.

Test coordinator Megan Parfitt said in a release by the company that the team recorded energy consumption of 141Wh per kilometre on a 10 degree day in Italy, which resulted in a 400km drive using a battery capacity of 60kWh and driving at 130km/hr.

“If we compare with other vehicles right now, Lightyear One can drive one and a half times further than a directly-comparable vehicle with the same battery size,” she said.

The test results build on a 710km drive on one charge in July 2021, when the car was driven at 85km/hr for 9 hours straight over a distance of 710km. At the time, the company said it was the longest distance any car had driven on a 60kWh battery.

Lightyear plans to commence production of a limited number of 946 Ones from the second half of 2022.

This article has been updated to correct the energy efficiency mesaurement to 141Wh/km.