# Is it possible to recycle vehicle emissions in order to generate elect

Iâ€™ve been doing some research and thinking recently into how vehicle emissions might be used to generate electricity in order to power the vehicle itself. Iâ€™ve seen a few products and research projects centred on this topic, although they all seem to be focused on converting the heat in the exhaust into potential energy.

Would it be possible to use a vehicleâ€™s emissions and force them through piping with large numbers of small generators, effectively creating a wind-farm within your own car. I respect it would take thousands if not millions of tiny wind turbines to complete this, but Iâ€™d really appreciate some help with regards to the equations and formulas of wind to potential energy conversion.

Could such a system be suspended using a helium balloon to lessen the weight exerted on the car?

If you had enough turbines could you simply use a very small amount of wind (vehicle emissions) in order to the supply the system?

Many thanks,
Jeremy.

## Answers and Replies

SteamKing
Staff Emeritus
Homework Helper
You might generate enough electricity to light a small bulb or two, but using thousands or millions of tiny wind turbines would not be very efficient. There is only so much energy in a car's exhaust stream, and dividing it up into smaller and smaller parcels does not create more energy, only less. That's why cars with turbochargers have one or two turbos: anything more complicated is more expensive to produce and less reliable in service.

Driving around with helium balloons suspended over your car is also problematic: how to be sure the balloon would not be ripped away going into a tunnel or under a bridge? Plus, you have to provide the car with extra power to overcome dragging a balloon around everywhere.

mfb
Mentor
The maximal energy you can get in that way is the kinetic energy of the exhaust, and that is tiny. Increasing the number of turbines does not help.
In addition, adding turbines would increase the necessary pressure in the exhaust line - and therefore the motor would need more power to push it out. I guess adding turbines would actually reduce the efficiency.

Could such a system be suspended using a helium balloon to lessen the weight exerted on the car?
Adding a helium balloon with any notable effect in terms of weight increases air drag so much that you cannot use it as a car any more. If you make it big enough, you get a Zeppelin ;).

If you had enough turbines could you simply use a very small amount of wind (vehicle emissions) in order to the supply the system?
No.