NAWA Racer's ultracapacitor 'harvests 80-90% of braking energy'

One of the flashier prototypes unveiled during the annual Consumer Electronics Show in Las Vegas was the NAWA Racer – an electric motorcycle with a difference.

The bike, which has a hubless rear wheel and sleek, futuristic design, has built-in ultracapacitors, which mean it can go up to 110km further on a single charge than a bike with just a battery pack. 

Unlike batteries, which store and release energy using chemical reactions, ultracapacitors store it electrically – like static collecting on a balloon. That means they can store energy a lot more quickly than even the best lithium-ion batteries without degrading – in lighter and smaller cells. However, they can’t yet store as much energy as a lithium-ion battery, and they don’t hold that energy for as long. 

That means they’re well-suited as a complement to existing battery technology rather than a replacement, although there are efforts under way to develop carbon-based supercapacitors for use in smartphones and other smaller consumer technology. 

The NAWA Racer has a 9kWh battery underneath a 0.1kWh ultracapacitor which can harvest 80-90% of the braking energy of the bike. However, you’re unlikely to see one of these on the roads – it’s a one-off prototype designed to showcase the carbon-based ultracapacitor technology, which is being touted for use in all sorts of electric vehicles in future.

Hybrid solution

“Electric vehicles are still limited by the energy their batteries can store and the time it takes to recharge them,” explained Pascal Boulanger, chairman of NAWA Technologies. “A promising solution is to combine lithium-ion with ultracapacitors – but until now they have not had enough energy, been too expensive and lacked the power capabilities to easily integrate them within a hybrid battery system.”

They could also be better for the environment. “Our ultracapacitors are based on carbon, which is naturally occurring and abundant, so our hybrid packs also reduce the need for lithium mining,” added Boulanger.