Regenerative braking refers to energy produced from braking and coasting that’s normally wasted, which is stored in a battery until needed by the motor. During electric motor drive/ assist, the electric motor kicks into gear, providing additional torque for such things as hill climbing, passing or quickly accelerating. For automatic start/ stop, energy is conserved while idling, as the engine is shut off when the vehicle comes to a stop, and is re-started when the accelerator is pressed.
Whereas a normal hybrid car simply combines an electric motor and a gas engine, a plug-in hybrid can run only on electric power, when charged, and can be recharged without using the gas engine. Plug-in hybrid electric vehicles (PHEV’s) have high capacity batteries, and charge by plugging into the grid, storing enough electricity to significantly reduce gas use.
There are two basic types of plug-in hybrids: extended range electric vehicles and blended plug-in hybrids. Extended range electric vehicles work by having only the electric motor turn the wheels, and can run only on electricity until the gasoline engine is needed to generate electricity to recharge the battery that powers the electric motor (or the gas engine can be eliminated entirely, on short rides). Blended plug-in hybrids work by still having both the gas engine and the electric motor connected to the wheels, both propelling the vehicle most of the time.
Electric vehicles (EV’s) drop the gas engine entirely, becoming much more environmentally friendly. The MPG goes way up, but the cost tends to go up as well, and the driving range goes down. These factors; the MPG, cost and range are tied to how efficient, how much capacity, the battery has. The higher the capacity of the battery, the higher the cost, MPG and range. Although EV’s emit no tailpipe pollutants, it remains important that the source for the energy from the grid that charges the vehicle’s battery remains green (i.e. renewable energy) as well.
Hybrid cars take numerous different forms, including the types mentioned above, and then compete against standard gas cars, flex-fuel vehicles, diesel vehicles, etc... European sales of standard hybrid vehicles have increased, but with roughly half the cars in the EU being more fuel efficient diesel engines, EV’s and plug-ins are the more popular choice. These cars can better compete in the global market, in terms of fuel efficiency.
The global hybrid market is still dominated by Toyota, in particular their Prius line, including the Prius Plug-in. The Prius remains California’s most popular car, as a testament to its global popularity. The Prius gets around 50 MPG, costs $25-30K and has a driving range of 540 miles on a full tank of gas. The plug-in model costs $30-35K and gets 95 MPG running on electricity only or 50 MPG running on both electricity and gas, with a driving range of about 600 miles.
The Tesla Model S and the Nissan Leaf are examples of successful electric vehicles. The Tesla Model S with a 60 kW-hr battery pack gets up to 102 MPG’s, costs around $70K and has a driving range of 208 miles on a fully charged battery. The Nissan Leaf costs $30-35K, can get 80 miles on a full charge and hits 128 MPG’s.
(*All figures are as of 2015.)