No, it's not utopia, but its likely to become darn close! Here's a
comparison. Mind you, these things aren't even available yet.
Electric
|
Gas
|
| Power: We are on the technology's
leading edge and power will, for a while anyway, probably several years,
be limited. The cost of components that can handle the high current flow
required would be prohibitive.
One advantage of electric is that power does not decrease with altitude
since the motor does not need air to run. Of course the thrust will still
be diminished up high due to thinner air on the propeller but the drop-off
will be much less than equivalent gas engines. |
Power: Gas rules here and likely will
for a long time to come. And it will be the 2-stroke that wins for
applications such as tandems and heavy pilot or flying at high altitudes. |
| Weight: The motor and frame will be very
light, probably a third of an equivalent gas version. Adding batteries
will make the weight about the same for the same endurance.
With enough battery power for a half-hour flight expect about 80% of
the weight of a similar power gas paramotor equipped with enough fuel for
a half-hour flight. |
Weight: They start out fairly heavy and
burn off about 6 to 8 pounds of that weight per hour. |
| Endurance: Limited by batteries. Current
estimates, based on flight testing by Csaba Lemak, are that with an
average weight pilot on an average wing, flight time would be an hour with
enough batteries that weigh the same as an equivalent power gas paramotor. |
Endurance: Gas rules here, too. Put
5 gallons of gas on an 80cc motor and you can fly forever, well, longer
than any bladder should reasonably be expected to hold out for anyway. |
| Cost (purchase): Initially will probably
be about $6000 to $7000 but that may come down if components can be found.
Right now, many prototype parts are machined. |
Cost (purchase): Between $4000 and $7000
new. |
| Cost (operation): An appropriately sized
electric motor with a prop directly bolted to it could be made to run for
thousands of hours. Lithium Polymer batteries can last for over several
thousand charge cycles. The electricity required to charge costs about
1/4th of gasoline so there is enormous opportunity to see costs reduced.
But even if the batteries only last for a thousand cycles, the cost will
be less than half of what a gas machine is. |
Cost (operation): On average, the
paramotor portion of cost is about $5 per hour for engine maintenance and
$5 per hour for fuel and 2-stroke oil. |
| Noise: Most paramotor noise comes from
the prop but it also comes from the redrive, intake, and exhaust. Given
that electric can do away with those items, it will be quieter--probably
by about 20% but that can be significant. |
Noise: Mufflers, intake silencers, and
quiet props can reduce the noise but only so much. |
| Transportability:
This is probably the single most revolutionary aspect for those who like
to travel with their PPG. Airlines currently allow carrying of the motors
and batteries on airplanes. Even if they were to outlaw the batteries in
checked luggage, they are easy and compact to ship.
Even in a car they are easier since the batteries
are simply unplugged which conveniently removes nearly half of the motor's
weight.
|
Transportability:
Anyone who has tried to transport a paramotor on the airlines knows why
this is problematic with gas motors.
Both the gas and oil are considered hazardous
materials and 2-stroke oil will become more difficult to come by as
4-stroke motors take over. If you cannot buy it locally, you'll have to
arrange shipping it. Then there's the whole hassle of buying gas storage
containers while at the destination. With an electric, all that is needed
is a charging system that can be run off the car.
|
| Training:
There are two great advantages: 1) the motor can more easily be detuned so
the student can't lift off until the instructor is sure he's ready and 2)
the weight can be started off much lower.
Having a light-weight "trainer" battery
pack can both derate the power and make it lighter. That would allow the
student to build up to full power and weight slowly and more safely.
|
Training:
While it is possible to detune a gas motor, it rarely happens due to
hassle and other risks. You can carry less fuel but that confers a smaller
weight reduction than is possible by carrying few batteries.
One advantage of a gas motor is that the clutch is
more likely to be used. Although it could be used on an electric,
that would be unlikely. It's not needed as much since the electric's prop
is not being torqued when the throttle is released nor is there much
rotating mass keeping it spinning at high RPM.
|
| Safety: There are some serious issues
that must be addressed since these motors will be able to go to full power
in any number of failure modes. This can, of course, be mitigated but must
be addressed.
There is opportunity to reduce injuries related to body contact with a
spinning prop during start since the pilot can put the motor on before
engaging the throttle and starting, per-se, is not required.
There appears to be little chance of the batteries exploding during
discharge but great care must be taken during recharging. |
Safety: Gas motors have proven a good
safety record in most regards. One area that has been problematic is
starting. A lot of pilots have had hands or other body parts injured while
starting with a pull start. |
| Reliability:
This is an unknown.
Batteries go bad, controllers fail, motors burn out and other maladies
befall them. However, looking at the R/C community, the opportunity for huge
reliability is there. As always, time will tell. |
Reliability: This is a known and it's
not very good. The chance of having something prevent you from flying a
gas paramotor on any given day is unpleasantly high. Engine failures,
while not a big safety risk due to our slow speed, are all too common. |
