Aside from the bicycle, the electric motor has the highest efficiency rating -- more than 90 percent -- of any mechanical device that converts energy to motion. What that means is that only 10 percent of the energy used by an electric motor is "wasted" getting the car moving. By comparison, the best efficiency rating for an internal combustion engine is about 20 percent, meaning that about 80 percent of the energy in a given amount of gasoline is used simply to get power to the car's wheels.
This is why cars generally get better mileage on the highway: Once a car gets rolling, it takes less energy to keep it rolling, allowing drivers to go further with less gas. Where a gas engine uses the most energy is where an electric motor conserves energy -- on the initial start.
Ganguly, as an engineer, knew all the moving parts of an engine -- cranks, gears, drivelines, differentials -- need to get moving before the rotary motion is transmitted to the wheels. Ganguly also considered an engine's "idle time." When a car comes to a stop, the engine has to keep moving and using energy to produce what is essentially wasted motion inside the vehicle in anticipation of the next time the car needs energy.
An electric motor solved both problems. An electric motor produces its maximum torque almost immediately. If the motor is linked directly to the wheels, that energy is instantly available to move the car. Plus, there's no need to keep the motor in motion when the car is idle. The motor can shut off to conserve energy. The Tiny also uses an unspecified number of sealed lead acid batteries, a throttle-like electronic controller, a converter and motors.
While Tara International hasn't yet divulged release dates for its other vehicles, the Tiny and its innovative simplicity may set the standard for EV use in the coming years.
For more information on the Tara Tiny and other electric vehicles, visit the links on the following page.
Related HowStuffWorks Articles
- Edmunds.com. "Car Cost Comparison." (Accessed May 5, 2009)http://www.edmunds.com
- EarlyElectric.com. "Electric Car History." (Accessed May 12, 2009)http://www.earlyelectric.com
- Hatch, Steve V. "Computerized Engine Controls." Eighth Edition, 2009, Delmar Cengage Learning.
- Khaund, Surajit. "State Innovator Develops New Hybrid Car." The Assam Tribune. January 8, 2008. (Accessed May 15, 2009)http://www.assamtribune.com/scripts/details.asp?id=jan0808/at04
- Tara International. "Battery Operated Four Wheelers." (Accessed May 5, 2009)http://www.tarainternational.us/FourWheeler.htm
- Tara International. "Profile." (Accessed May 22, 2009)http://www.tarainternational.us/profile.htm