Without going into physics and reading past the first page, there is something wrong with the camera. It never gets ahead of the vehicle to show nothing is pulling it.
Second, how did the vehicle move so straight for so long?
It is not a hoax. A hoaxers generally do a more convincing job than alt.science. Hoaxers generally know enough to fool a sophisticated viewer.
Where's the fire?:
My reaction was not that it has achieved any notable speed, but why did it take so long to get there ?
This is not an experiment, as such, but "film until we get the effect that we want, then stop". Some fall for the most simple deceptions.
Direction:
The question of direction can be many things, but need not be a mystery. The front wheel is probably lightly loaded. The cart is so inefficient that there must be considerable drag, so perhaps it is simply a case of the rear wheels following the camber of the road. Could be any number of things. It is only necessary to raise these questions, if you feel that there is something to be explained.
Speed:
The machine has its wheesl coupled to the prop. It will move forward by the wind driving the prop, hence the wheels. It will accelerate until the drag (entire vehicle) and the motive force (energy gained from the wind) match.
This point will be below windspeed.
At this point, there are opportunities for other mechanisms to take a role.
Note that the wind is gusty, and the prop. massive. The whole premise of the notions (not theory) that support these designs, is due to the fact that
the wheel are connected to the prop.
But, as you can see, the wheels are tiny, and the road rough, so contact with the road will be discontinuous.
At speed, the prop and cart have accumulated a great deal of kinetic energy.
If the wheels leave the road, this means that the wind can drive, the prop. alone. The vehicle's momentum will carry it forward, but it also allows additional energy to be stored in the prop, as it is essentially free-wheeling.
Contact with the road, is resumed, and the the vehicle accelerates a little more, until the next perturbation upsets the balance that normally occurs when drag limits the velocity. Through this mechanism, and perhaps a boost gained from wind bursts, the vehicle's velocity increases until some other effect takes over.
It is a device that accumulates kinetic energy gained from the wind, and stores or releases it due to random disturbances, meaning that the drag/motive energy budget is biased in favour of motivation, so it can accelerate to a velocity beyond that expected.
It is such a bag of bolts, and the experiment so poorly executed, that it does not warrant further analysis.
Conclusion:
A very inefficient way of gathering wind energy. Myth busted, use a sail.
