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There are few, if any, design compromises that have to be made to incorporate TheWheel™ into any application. It is virtually free of noise and produces by itself no emissions. Initial results have yielded energy efficiency for TheWheel™ of greater than 90% This result was confirmed by connecting one TheWheel™ with a
solid shaft to another. By
providing electricity to power one TheWheel™ we
were able to measure the electricity generated by the non-powered unit. The difference between the electricity
input and output thus established the loss of energy of the combined wheels. Most electric engines may lay claim to a similar efficiency as demonstrated with TheWheel™, but this is only at their initial point of output, the shaft coming out of a stationary motor, and not, as is the case with TheWheel™, at the contact point with the road. Conventional electric vehicles customarily make use of the same energy transfer systems found in vehicles with fossil fuel engines, which utilizes multiple cogwheels and bearings embedded in gearboxes, differentials, and shafts to power the wheels. Together these conventional components represent a formidable resistance usually absorbing roughly 50% of the energy input under nominal driving conditions. It should be noted that gearbox efficiency, often
touted to be quite acceptable, is usually actually measured at peak power only. With the exception of racecars,
however, rarely ever is a vehicle operated for extended periods of time at peak
power. Peak power and torque is
usually 6-8 times higher than required for nominal driving conditions. The resistance of the gearbox and other running gear is
more or less constant and poses a significant energy burden at the nominal
operating range. Unlike as would be the case with the direct drive
configuration of TheWheel™
with an extremely low resistance, a person is usually unable to rotate a wheel
of a conventional vehicle that is “in gear” without extraordinary force (see
also:
Friction Reduction) Fossil fuel engines typically have
a fairly low efficiency rating of less than 50%. This means that only 50% of the potential energy within the
fuel is realized at the initial point of output, the crankshaft. Combining the low efficiency of
fossil fuel engines (<50%) with the additional loss of power through the
energy transfer systems (50%) an efficiency of less than 25% is ultimately
experienced at the wheels. Obviously
the current system with TheWheel™ relies
on fossil fuel powered generator to augment the batteries should they become
drained. Nevertheless, experience has shown
that, at their worst, TheWheel™
equipped vehicles should use less than a third of the energy of conventional
vehicles, during a duty cycle.
* Not including the efficiency of
the electricity augmentation devices The geared traction applications with electric engines, as found in the current offerings of hybrid vehicles, are bound to yield less than optimum efficiency results. The development of fuel-cell technology will depend greatly on the efficient use of the energy generated. The more efficient the energy generated by a fuel cell is being used the more economically viable such a system becomes. With 50% efficiency advantage over geared electric engines, TheWheel™ is ideally positioned to enhance chances of a successful introduction of the fuel-cell technology. The influence of a gearbox on fuel consumption The impact on fuel consumption of the correct choice of
gear is illustrated with photograph of the speedometer of a Lancia MPV below
driving at constant speed of 80 km/h in 4 different gears (2nd through 5th).
While the demand for power at the wheel remains constant the demand on the
engine is reduced as a higher gear is selected (from
The fuel consumption dropped from 12.6 liters per 100 km in 2nd gear, 10.2 in 3rd, 7.9 in 4th, to 6.5 liters in 5th gear (all else being equal).
Choosing the correct gear reduces fuel consumption by 51% Example: energy consumption in forklift trucks Electrical vehicles utilizing gearboxes and differentials are subject to the very same resistance. Take, for instance, the example of two comparable 4 Metric Ton forklift trucks one conventional with gearing and the other utilizing TheWheel™. The conventional (Montini) forklift truck: Energy consumption with wheels off the ground:
Energy consumption with wheels on the ground:
The Heinen Coefficient:
TheWheel™ powered forklift truck: In comparison the Hydraulic Free Operation (HFO) forklift truck build by e-Traction® for SKF utilizing two TheWheel™ SM500/1 motors have a combined resistance of only 1.9KW (about one fifth that of that measure on the Montini truck) when its wheels are off the ground.
The influence of resistance on battery endurance (Montini versus SKF) Montini forklift truck: One 16 KW motor, Batteries 1,250Ah at 80V, The driving time is 140 Amp is measured with a fully loaded truck at top speed of 17 km/h, Measured power consumption of the gearing is Measured power consumption with a 4 metric ton load is Power used exclusively to move the forklift truck with a full load is 5.2 KW, Maximum endurance of the unit is 7 hours.
SKF HFO forklift truck: Two 7.5 KW TheWheel™ each (jointly 15 KW), Batteries 1,250Ah at 80V, Energy required: Measured energy requirement of the unit 24 A x 80V = 1.9kW, Total required energy is 5.2 + 1.9 = 7.1 kW, With TheWheel™ traction and identical battery storage the
unit was able to operate 12.8 hours which resembles
an 80% endurance improvement. Example: energy consumption of People Mover Vehicles As a consequence of a 1996 research assignment for FROG navigation systems we discovered that the use of gearboxes in electric vehicles (proven technology) is bound to lead to disappointing results. PMV project Schiphol long term parking (FROG) and Rivium
Conventional (proven technology):
While this was not really acceptable for the client there appeared no alternative. These findings were a key contributor to the development of TheWheel™ and below you will note the significant endurance enhancement difference achieved (not to speak of the many other technical and operational benefits TheWheel™). TheWheel™:
A TheWheel™ vehicle has a 52% improvement in endurance and a 20% higher top speed. This means it could cover a distance 80% greater than its conventional counterpart. This is not taking into
account a phenomenon discovered in the late 19th century by Mr.
Peukert* that when batteries are taxed less severely they will operate more
efficiently.
Frog PMV Mouse PMV The influence of resistance on battery endurance (Frog versus Mouse) With the wheels off the ground when the tractive force is used exclusively to make the cogwheels rotate at 2,250 RPM without external load, the measured value of the Frog was:
Energy consumption: which means At the maximum speed of 25 km/h a distance of The Mouse PMV of the Koningin Juliana Toren has two TheWheel™ SM500/1 motors. The measured value of energy consumption is 70 Ampere at 96 Volt which corresponds with 7 KW. To make a fair comparison we converted these values to their 48 V equivalent, which is 140 Amp. The speed for this vehicle is 25 km/h as well. Energy consumption 1,250 Amp x 0.9 = 1,125Ah effective. This means 1,125 Ah / 140 Amp equals 8 hour effective driving time. Under comparable circumstance the Mouse can cover a distance of 200 km while the Frog only covers 88 km. That is an improvement in endurance of 130% or 2.3 times the distance. If greater distances can be covered by one vehicle than less vehicles are needed to do the same job. That means a reduction in both the cost of personnel and equipment. And maybe more importantly; a reduction of the burden on the environment and the earth’s scarce energy resources. *Mr. Peukert discovered that a 100 Ah battery discharged at a 5 Amp rate will last 20 hours (5*20=100), but if it were discharged at 20 Amp it will not last 5 hours but only 3 hours and 20 minutes. Through careful measurement he was able to determine an equation that accurately relates the size of the battery, the discharge rate and the amount of energy remaining. Peukert’s law mathematically states the relationship between effective current and actual current (graph below).
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; 
;
(3.5
hours of effective driving time). 
can
be covered. 