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Newton's third law problem.

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fourfathom:

--- Quote from: electrodacus on November 27, 2022, 03:42:16 pm --- there will be zero way to claim that direct upwind can happen without energy storage.
As that equation states that to move upwind you need more power than what is available to vehicle in ideal case from the wind.  Ideal case vehicle will be in equilibrium.
--- End quote ---

"And yet it moves."

Energy storage?  Think about it a bit.  If you can move upwind or downwind with energy storage, you can move upwind or downwind with sufficiently low gearing -- no storage required.  Storage is irrelevant and unnecessary.

And now I have hit my daily limit for this thread.

electrodacus:

--- Quote from: fourfathom on November 27, 2022, 03:55:18 pm ---
"And yet it moves."

Energy storage?  Think about it a bit.  If you can move upwind or downwind with energy storage, you can move upwind or downwind with sufficiently low gearing -- no storage required.  Storage is irrelevant and unnecessary.

And now I have hit my daily limit for this thread.

--- End quote ---

A gearbox can not amplify power.
If to drive upwind requires more power than available form the wind. How do you get the extra power if not from stored energy?

Kleinstein:

--- Quote from: electrodacus on November 27, 2022, 04:00:02 pm ---A gearbox can not amplify power.
If to drive upwind requires more power than available form the wind. How do you get the extra power if not from stored energy?

--- End quote ---

There is not need to have more power than the wind, it is only about having more force available than the wind.

With the wind much faster than the movement to ground the force from the wind is approximatedly constant. The power needed is just force times speed. So zero power at zero speed and little power needed at low speed.
The gearbox can not amplify power, but it can amplifiy the torque / force.

electrodacus:

--- Quote from: Kleinstein on November 27, 2022, 04:32:35 pm ---
There is not need to have more power than the wind, it is only about having more force available than the wind.

With the wind much faster than the movement to ground the force from the wind is approximatedly constant. The power needed is just force times speed. So zero power at zero speed and little power needed at low speed.
The gearbox can not amplify power, but it can amplifiy the torque / force.

--- End quote ---

Vehicle will not need zero power to keep the vehicle at equilibrium point and zero speed.
You are thinking about having the vehicle anchored to ground by applying brakes but that just makes the entire earth part of the vehicle so no longer separated.
Please imagine a vehicle that has no brakes then think about the amount of power needed to keep the vehicle stationary based on wind speed and vehicle effective projected area facing the wind.
If you apply no power the vehicle will be accelerated in the direction of the wind and you need to match that power in ideal case to stay at zero speed then you need extra in order to move upwind.

PlainName:

--- Quote ---Not quite sure where the wrong equation many of you are using originated.  Can someone point to a source for that equation and I'm not referring to Wikipedia.
--- End quote ---

And yet it's OK for you to copy random equations from t'web to prove ... something. Why not actually write yours1 from scratch instead of copying someone elses thing meant for some different scenario? You might learn something.

---
[1] You don't seem to have made one yet. You've copypasta'd many.

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