The idea of electric cars has been around since cars became a popular form of transportation. Modern versions of electric vehicles are growing in popularity due to their environmental impact. Growing concerns around global warming and greenhouse gas emissions has influenced the transportation sector to rethink energy efficiency. The standard car is run by an internal combustion engine which at best is roughly 30% efficient. In other words, 30% of the energy stored in gasoline is used to move the car. New technology that is incorporated into the latest electric cars, like the Tesla Roadster, is almost 90% efficient and produces nearly zero emissions.
The Tesla Roadster is powered by an electric motor. The reason why this motor is so efficient is because the motor also acts as a generator when the the car is not being accelerated, turning mechanical power into electricity. The Roadster uses a three-phase Alternating Current (AC) Induction motor, a very reliable, simplistic, and efficient motor. The motor has two primary components, a rotor and a stator. The rotor is a steel shaft with copper bars running through it, it rotates and turns the wheels. The stator surrounds the rotor but doesn’t physically touch it. The stator creates a rotating magnetic field, creating a current in the rotor. The current in the rotor ‘chases’ the rotating stator and produces torque which moves the wheels. This motor operates very quickly allowing the vehicle to accelerate faster than sports cars. Since the Tesla Roadster is an electric vehicle it needs to be charged when the battery is low.
Tesla offers 520 charging stations called ‘supercharger stations’ that are spread out all throughout the United States. These supercharger stations are able to fully recharge the car in only a few hours and are very easy to use. The chargers deliver up to 120 kW of direct current (DC) directly to the battery, which can power the battery for a range of 170 miles in 30 minutes. Charging your car is as easy as charging your phone, all you have to do is plug the adapter into the vehicle. Tesla plans on building more charging stations in the near future.
Personal vehicles account for over half of the transportation sector’s emissions, and the transportation sector accounts for about 27% of the our total greenhouse gas emissions. There are over one billion vehicles on the world’s roads today heavily contributing to global warming. In order to become more energy efficient and to lower the amount of C02, more people should invest in the very energy efficient electric cars.
Source 1: http://my.teslamotors.com/roadster/technology/motor
Source 2: http://www.teslamotors.com/supercharger
Source 3: http://www3.epa.gov/climatechange/ghgemissions/sources/transportation.html