Primer on automobile fuel efficiency and emissions

The purpose of an automobile’s engine is to convert the chemical energy of the fuel into kinetic energy – or motion – that powers the Transportation is one of the fastest-growing sources of GHG emissions in the industrialized world today. [...] The smaller the particle, the deeper it may enter the lungs and theoretically, the greater the damage it can cause. [...] However, only a fraction of the energy in the fuel is utilized to move the automobile – in fact, in a typical gasoline-powered vehicle being used for urban driving, only about 13 per cent of the fuel energy that is delivered to the engine actually makes it to the wheels to move the vehicle. [...] Primarily, energy is lost as heat when it is expelled through the exhaust and the cooling system, and as friction in the engine and drivetrain (i.e., the series of components that link the engine and the wheels). [...] Approximately 63 per cent of the energy (69 per cent in highway driving) is lost to engine friction caused by the pumping of air into and out of the engine, as well as waste heat that is passed out through the exhaust system and the engine cooling systems when the vehicle is providing power to the wheels.