The Story of the E-Tracer
PIAXP X-Tracer Team Switzerland Story
The sight the Peraves’ E-Tracer® cornering at a 52-degree lean instills awe, if not trepidation.
But fear not, this electric-powered cabin motorcycle was engineered for safety as well as fun and efficiency. Accelerating to 60 mph in under five seconds, at top speed of over 150 mph and covering a distance of 150 miles on a single one-hour battery charge, the X-Tracer Team Switzerland’s entry in this year’s Progressive Insurance Automotive X PRIZE (PIAXP) competition is likely to zoom off with first prize in the alternative class...
Explains Riedener: “Upon the arrival of lithium cells in 2000, it was clear that the first purely electric high-performance road vehicle would be the ‘smallest available two-seater plane without wings’ -- which is, incidentally, the MonoTracer!â€Â
And it is at this crossroads where we, and the Peraves cabin motorcycle, encounter the hummingbird and the swan.
Core members of the X-Tracer team have also been electric model RC flying enthusiasts for two decades. This experience provided key input into their 2007 proof-of-concept prototype of the E-Tracer®, the first electric cabin motor cycle.
The comparatively small size and extremely low drag of the E-Tracer due to it’s single track and the tandem seating allows, by the laws of physics, scaling of the electrical drive comparable to a small airplane. This could never work in a normal-size car. The inner circles of airplane design refer to this phenomenon as the Hummingbird-Swan-Effect:...
In fact, fossil fuel remains a highly “efficient†energy source. One kilogram of premium fossil fuel packs more than 12,000 Wh of thermal energy whereas the same amount of the best lithium ion cells has just attained 200 Wh of usable storage. The sad truth is that 90% of the planet’s fossil fuel resources have been squandered on cars that run on 10% energy efficiency. By contrast, the E-Tracer carries 120 kg of Li-Ion cells on board, but maximizes its energy efficiency to 90%. Thus 120 kg of Li-Ion cells, equal to just 2 kilos of gasoline, at 90% efficiency powers the E-Tracer at a rate of 300 MPG.
The PIAXP requirement of 100 MPGe pushes the physical limits of what we all recognize as a car  however reduced its bulk, weight, or friction, and whatever its drive: turbo-diesel, hybrid, or pure electric.
On the other hand, the physical limits of a 1200-pound, fully-enclosed tandem two-seater with a one-track main running architecture and an additional extendable three-track maneuvering system lie somewhere between 350–400 MPGe. This leaves a lot of room for fun in the E-Tracer, which easily achieves 200 MPGe during sporty driving. The X-Tracer Team elaborates on just a few points:
· We don’t have to use thin wheels and pump them up to 50 psi.
· We don’t have to use rear-facing cameras as mirrors.
· We do not shave off every ounce of weight and can therefore invest in some luxury.
· Aerodynamics don’t have to compromise daily usability, as is the case in many of today’s cars.
· We don’t have to worry about passing the slow 18-wheeler in front of us on a two-lane road, we just do it.
· We can overpower the E-Tracer with a 204-hp electric engine, resulting in a very sporty 10-lb/hp weight-to-power-ratio fully loaded with two occupants. This is clearly Porsche Territory.
In fact, fossil fuel remains a highly “efficient†energy source. One kilogram of premium fossil fuel packs more than 12,000 Wh of thermal energy whereas the same amount of the best lithium ion cells has just attained 200 Wh of usable storage. The sad truth is that 90% of the planet’s fossil fuel resources have been squandered on cars that run on 10% energy efficiency. By contrast, the E-Tracer carries 120 kg of Li-Ion cells on board, but maximizes its energy efficiency to 90%. Thus 120 kg of Li-Ion cells, equal to just 2 kilos of gasoline, at 90% efficiency powers the E-Tracer at a rate of 300 MPG.
The PIAXP requirement of 100 MPGe pushes the physical limits of what we all recognize as a car  however reduced its bulk, weight, or friction, and whatever its drive: turbo-diesel, hybrid, or pure electric.
On the other hand, the physical limits of a 1200-pound, fully-enclosed tandem two-seater with a one-track main running architecture and an additional extendable three-track maneuvering system lie somewhere between 350–400 MPGe. This leaves a lot of room for fun in the E-Tracer, which easily achieves 200 MPGe during sporty driving. The X-Tracer Team elaborates on just a few points:
- · We don’t have to use thin wheels and pump them up to 50 psi.
· We don’t have to use rear-facing cameras as mirrors.
· We do not shave off every ounce of weight and can therefore invest in some luxury.
· Aerodynamics don’t have to compromise daily usability, as is the case in many of today’s cars.
· We don’t have to worry about passing the slow 18-wheeler in front of us on a two-lane road, we just do it.
· We can overpower the E-Tracer with a 204-hp electric engine, resulting in a very sporty 10-lb/hp weight-to-power-ratio fully loaded with two occupants. This is clearly Porsche Territory.
· With over 1100 Nm always available at the rear wheel, there is plenty of safe acceleration on tap to cope with the ever-decreasing gaps in today’s traffic. This is more like Ferrari or Lamborghini Territory.
· All this with a 150-mile range and a 250-pound battery for 10’000 US$ at this time of writing. Prices per kWh will eventually come down by 30-50%, but not like with DVD Players, cellphones or flat-screens by 90% in ten years. Batteries are mainly made out of resources, and not of engineering or marketing costs.
