Why dont we use rotational energy from vehicles to convert into electrical energy?

Replies

• 

  Ramani Aswath

  jarpala venkates

  why don't we utilise it??

  1. Because there is no free lunch.
  2. The Second Law of Thermodynamics limits that idea.
  3. That idea is used for regenerative braking in vehicles. This application does not violate the Second Law.
  
• 

  Ashraf HZ

  Regenerative braking is used with good effect in hybrid cars.
  
  I alternate between driving a hybrid and a normal petrol car. Every time I brake hard on the petrol car, I cringe as I picture the huge amount of heat energy dissipating and untapped 😔 I think they should just make regenerative brakes standard in cars.
• 

  jarpala venkates

  of course,is there is no any possibilities regarding that idea?
• 

  Ramani Aswath

  I am afraid not. Mainly because such rotational energy in vehicles is provided by the fuel running the vehicle. Any conversion of such rotation to electricity will only result in a higher fuel consumption. One can as well use a direct fuel-electric generator, which is specifically designed for good efficiency.
• 

  Kamlesh Vora

  Well, I would like to speak in no techie language.
  Our fossil fuel burns into Engine which converts into mechanical energy and transmitted to the wheels through many linkages, and gears etc. during this process the vehicle itself losses much energy and the final wheel gets only 15% of the fuel burned. Engine, Mechanical frictions, aerodynamic drag, rotational or rolling resistance on wheels, etc.
  after this only actual 15% energy left for moving your vehicles wheels.
  In this 15% you decide to use regenerating, then what is the use of Alternator underhood, which gets drive from engine only.
  In hybrid engines they have inhub motor on crackshaft and smart ECU (computer) they work with together and decide when to stop car engine and run on electric power stored in batteries.