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Very long run on electricity.

I have an idea how to make the long drive Model S for Electricity. I plan to use the power of resistance of the air flow, which occurs when driving a car. Do you think that is possible?

:-D

I need a sponsor and a little bit of time, or a little more time. I'll prove to you all that this works.

Hi Anton,

I for one hope you do. (I also would like us to solve the faster than light drive problem, and cold fusion, but that's another matter...)

These things which I just mentioned are prohibited by the laws of nature. Not suggestions or good ideas of nature, but LAWS. For hundreds of years, people have tried to create machines that produce more energy than it takes to run them. No one has succeeded, and in every failure, we can trace the fundamental problem back to the Laws of Thermodynamics.

The best advice we can give you is to study the Laws of Thermodynamics, especialy the First and Second Laws of Thermodynamics and make sure you understand the implications of them. These two laws explain all failures of devices that try to produce more energy than they use to run.

Many people have brought ideas similar to yours to the Tesla forum. Many people responding to your message have seen this discussion 4 or 5 times already, which is why their response has been negative.

Hope this helps.

At the risk of breathing new life into this dead horse...

http://www.freerepublic.com/focus/f-chat/2392022/posts

Anton system sounds far too implausible simply by virtue of the excess energy claim alone.

However, harnessing waste energy doesn't violate the laws of TD or Entropy. This would be far less ambitious, and so the question is why do it?

I'd only say why not if the system doesn't add excessive weight or if you just wants to have a fun little project.

--- Cherif

Because it will slow you down. The windmill slows more than its output accelerates. Always. What fun!

However, harnessing waste energy doesn't violate the laws of TD or Entropy.

That's true, but you need to define "wasted energy". Airflow you would use is not wasted energy, kinetic energy you could harness from it is created by movement of the car.

Point to notice: movement of the car.

Just by first law of thermodynamics you can't get anything out there without slowing down the car (chain of energy conversions will get you back to battery). Only way for those to work would be to same time lower the car Cd enough to compensate that energy gain. That's unlikely.

The only way this is going to work is if you can harness the power of the wind. A team did what many people thought impossible and used a wind-driven propellor to drive a vehicle twice as fast as the wind was blowing: http://phys.org/news/2012-07-blackbird-cart-fast.html

But beyond that I agree with Timo that only by harnessing "wasted energy" (strict definition) will you get any benefit.

It may be helpful to discuss sailing. Sailboats go faster than the wind when going nearly into the wind and slower when traveling with the wind. Obviously this doesn't violate any rules and the reason is that when traveling into the wind the apparent wind plays a role. Apparent wind is the wind experienced at a particular speed. When going upwind this increases and when going downwind it decreases.
For a windmill on a vehicle the apparent wind to consider it that on the blades not the vehicle. Apparently, some one has managed to go dead downwind faster than the wind using mounted windmills.

http://www.skepticblog.org/2010/05/27/sailing-directly-downwind%e2%80%a6...

Is this a hoax?

The piezoelectric devices described in the article would, as a matter of fact, harness the waste energy of air turbulence. For big trucks with high Cd, there is a lot of turbulence behind them. Also there is some on the aft surfaces of most cars. Of course, if the devices are mounted in unobstructive way, flush to the surface, and not increasing the Cd with their vibration.

But with the very low Cd of the Model S, I doubt that there is anything worth recovering, leave alone the complexity. Just further lowering the Cd can probably be more beneficial.

The energy in the turbulence is also a function of the car's motion, so the best result obtainable is some fractional recovery of that.

There is a strict distinction between harnessing external air movement (wind) and exploiting your own motion's air resistance to increase your motion. The latter is a nonsense. (Non-sense.)

Brian -- The energy in the turbulence is also a function of the car's motion, so the best result obtainable is some fractional recovery of that.

The corollary is: The more aerodynamic the vehicle is the less turbulence energy will be available, so it's going to be more cost effective to reduce aerodynamic drag as opposed to adding additional complex generating systems. Regenerative braking is only effective because if you have an electric motor you also have a generator so the additional cost is a bit of software development and a few minor hardware pieces.

This energy flow definitely shows a net loss.
Happy Holiday!

@jerry3: +1. Exactly what I said...