Using Sailing to Create Thrust
Concept of sailing: Make the body of a car act as an airfoil that is vertical similar to a sail on a sailboat. This will turn the force of winds into forward thrust used for speed/efficiency.
Therefore in a crosswind (blue arrows in diagram below) there will be a force exerted forward left to the car (if it's designed like a vertical airfoil). But to create forward thrust and not forward left, boats have the keel (the thing under a boat) that creates a force to the left. The steering fairing design would have to somehow mimic this to create forward thrust.
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Example of Boat Kneels
Turns out in our glory years in 2012 the car used sailing so maybe rip off some info from those days.
Pros
Gain of speed and efficiency over distances
Some top performing cars take advantage of this
Cons
Possibly difficult/time consuming to design and manufacture
Different locations and tracks will have significant impact on this system
Examples of past cars that utilized sailing:
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Note: This car used crab steering to help the “sailing” effect described above
Important Notes
As per https://materialdistrict.com/article/solar-car-sails-wind/ the race track is typically a straight line with winds mostly coming from the same direction
This would massively increase the benefit of the sail
The car’s canopy and wheel were specially designed for this
Also has a detachable wing to help panels collect more wind