Motorcycles

Nawa's ultracapacitor-hybrid e-moto radically boosts power and range

Nawa's ultracapacitor-hybrid e...
The wild, hubless Nawa Racer offers massive range and acceleration at low weight and cost thanks to an ultracapacitor hybrid energy system
The wild, hubless Nawa Racer offers massive range and acceleration at low weight and cost thanks to an ultracapacitor hybrid energy system
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While these are just renders, we've seen the actual bike under construction in the lead-up to CES 2020
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While these are just renders, we've seen the actual bike under construction in the lead-up to CES 2020
The Nawa Racer offers a 300-km urban range in a bike that weighs just 150 kg
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The Nawa Racer offers a 300-km urban range in a bike that weighs just 150 kg
Nawa has designed and built the bike in conjunction with UK-based design house Envisage
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Nawa has designed and built the bike in conjunction with UK-based design house Envisage
The Racer has a supercar-like 0-100 km/h time under three seconds
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The Racer has a supercar-like 0-100 km/h time under three seconds
The bottom half of the bike's "chest" is a 9-kWh lithium battery pack. The top houses a 0.1-kWh Nawa ultracapacitor
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The bottom half of the bike's "chest" is a 9-kWh lithium battery pack. The top houses a 0.1-kWh Nawa ultracapacitor
The wild, hubless Nawa Racer offers massive range and acceleration at low weight and cost thanks to an ultracapacitor hybrid energy system
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The wild, hubless Nawa Racer offers massive range and acceleration at low weight and cost thanks to an ultracapacitor hybrid energy system
The Nawa Racer promises superbike-level acceleration thanks to an ultracapacitor hybrid energy system
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The Nawa Racer promises superbike-level acceleration thanks to an ultracapacitor hybrid energy system
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This sweet-looking electric motorcycle has a relatively small, lightweight 9-kWh battery, and yet it boasts a 300-km (186-mi) urban range and superbike-level acceleration thanks to an ultracapacitor hybrid energy system unlike anything we've seen before.

Ultracapacitors can charge and discharge almost immediately, and last millions of cycles, making them perfect energy storage units for extreme power outputs and rapid charging. On the other hand, their poor energy density makes them nowhere near as compact as lithium batteries, and they leak energy over time, so they're not great as the sole energy storage unit on a vehicle.

Where they really shine, according to French ultracapacitor manufacturer Nawa Technologies, is in a hybrid setup paired with a lithium battery, creating a power unit that augments the density and storage capacity of a lithium unit with the rapid charge and discharge rates of a capacitor.

If you've ever wondered why regenerative braking puts such a small amount of energy back into the battery, the answer is simple: the battery is the bottleneck. Lithium battery charge rates are so slow that the battery simply can't recoup much of your deceleration energy. An ultracapacitor, on the other hand, has no such limitations.

"It's recouping 80-90 percent of the energy of your braking," Nawa CEO Ulrik Grape tells us, "and letting you use that right away when the light goes green."

In a stop-start urban environment, that makes for a hugely efficient electric powertrain that can squeeze a ton more range out of a given battery.

The bottom half of the bike's "chest" is a 9-kWh lithium battery pack. The top houses a 0.1-kWh Nawa ultracapacitor
The bottom half of the bike's "chest" is a 9-kWh lithium battery pack. The top houses a 0.1-kWh Nawa ultracapacitor

Nawa is building this bike – the Nawa Racer – as a technology demonstrator for CES 2020. It's a super-sweet looking futuristic cafe racer with an attention-grabbing hubless rear wheel drive rated for 99 horsepower (74 kW). It'll do 0-100 km/h (0-62 mph) in a time "comfortably under three seconds."

The Racer's energy storage is split into upper and lower halves, the bottom half being the heavy 9-kWh lithium battery pack, and the top housing Nawa's capacitor pack. It's neatly split for visual purposes – a terrific job by UK-based design firm Envisage Group.

A 9-kWh battery pack would normally be good for an urban range around 180 km (110 mi) if we use the range figures for the 7.2-kWh Zero S as a guide. But the Nawa bike adds a relatively tiny 0.1-kWh ultracapacitor on top and massively increases that range to a claimed 300 km (180 mi), purely by harvesting and reusing so much braking energy.

If you wanted to get that range out of lithium batteries, you'd have to add a whole lot of weight and expense. The bike might end up close to 200 kg (440 lb). The ultracapacitor, on the other hand, only adds about 10 kg, resulting in a total bike weight of just 150 kg (330 lb) for the Racer.

And Grape tells us that in an application like this, it's a relatively inexpensive thing to build into the bike.

"I don’t think in this kind of configuration it’ll add more than a few hundred dollars," he says. "We’ve said before, if you reduce the size of the battery and add an ultracapacitor, it would not be an overall cost adder. It would likely make the overall package a lower cost solution."

The Nawa Racer offers a 300-km urban range in a bike that weighs just 150 kg
The Nawa Racer offers a 300-km urban range in a bike that weighs just 150 kg

Of course, something like this will make a lot less sense on the highway.

"The urban environment is where this combination truly shines," says Grape. "All the stopping and starting, that’s lost energy that we can reclaim. The u-cap only stores a small amount of energy, but it’s being used very efficiently. We’re basically pumping that ultracapacitor in and out the whole time through acceleration and braking."

Nawa isn't planning to build or commercialize this bike; its business is the ultracapacitors themselves, and the company is taking delivery of manufacturing equipment in the new year with plans to start production at scale in 2020.

The Racer is merely a demonstration of what the technology can do, when paired with a regular battery-electric powertrain. Electric vehicles are already terrific around town, but ultracapacitor hybrid systems stand ready to make them lighter, cheaper and capable of monstrous acceleration for short bursts.

Nawa is hoping to entice a few car and motorcycle manufacturers to build the tech into production vehicles, becoming an OEM component supplier. Indeed, as the Lamborghini Sián demonstrates, there's no reason why hybrid capacitor systems can't be used to radically boost the acceleration and efficiency of combustion cars as well – let alone smaller vehicles like bikes, scooters and other electric commuting machines.

We hope the tech gets implemented in a road-going vehicle post haste, so it can be fairly tested against the status quo, but it sure seems like a step forward for urban electric mobility.

You can learn lots more about Nawa's ultracapacitor technology in our overview from 2018. Check out a video below.

Nawa Racer - world's first hybrid ultracapacitor battery-powered e-bike

Source: Nawa Technologies

View gallery - 7 images
17 comments
VincentWolf
Just imagine a tesla with this system. Perhaps the new 2020 roadster will feature it and thats what musk meant by 'rocket thrusters'
Phileaux
Garbage Truck would be a perfect test bed! Its mostly stop and go until it's full and have to haul to dumping site.
JamesGibsonIII
I've been waiting for Tesla to implement this. I thought that's why they bought ultracapacitor maker Maxwell Technologies.
Gannet
Gees, if this doesn't get the manufacturers attention, I don't know what will. Tesla recently bought Maxwell, supercapacitor company that also has battery technology. Many thought it was for the battery tech, but maybe for both ??
usugo
for a moment there I thought Nawa was making realistic claims. But then, I read "Nawa bike adds a relatively tiny 0.1-kWh ultracapacitor ". It can have 80-90% recuperation efficiency, but there is no way, decelerating generates just 100W, and that can increase range of 30+%. I call it BS, the numbers just don't add up.
Bob Stuart
Bicycle couriers are notably quick, yet they make little use of the brakes. This must be for riders who can't anticipate traffic lights because they only love acceleration.
MD
usugo: you missed the "h". 0.1kWh = 360kJ (360000 J = Ws : Watt Seconds) of Energy. NB. that is the same as 36kW for 10 seconds, or lets go crazy, 360kW in 1 second (that is some pretty hard braking... for such a light vehicle, lets say the average hard stop lasts 3 seconds, so we can split the Energy over that time and come up with something like, 130kW of braking energy... (220kg at 100km/hr ~= 84.8kJ ~= 23.5Wh or 0.023kWh. The energy storage should be sufficient.... (I may have some errors in my quick figuring, but the essence is that it should work... (to a factor of 5)
guzmanchinky
That bike looks the proper business
Mzungu_Mkubwa
I think this is a fantastic concept that should have been put in place in hybrids a decade ago! This is the perfect kind of application for supercaps! I would love it if someone would come up with a retrofit supercap regen-braking system for existing vehicles that was in a form factor that would slip in place of existing disc brakes! It would be simply for use at (annoyingly frustrating) stoplights that pepper US communities. Controls could be supplemental to or integrated into existing accelerator & brake pedals. I believe this kind of system would save so much in fuel and brake wear as to pay for itself pretty quickly...
alan c
I make it 0.0236Kwh kinetic energy of a 220kg object moving at 100Kph, using an online calculator. So in theory the supercapacitor could store all the energy from bike and rider moving at 200Kph.