An Electric Vehicle( EV) is a vehicle that includes an electric motor and runs on electricity. Propulsion in these vehicles occurs by one or more electric motors that are powered by rechargeable batteries. Unlike fossil-fuel powered vehicles, the electricity for EVs can be generated from a wide range of sources including nuclear power, solar power, tidal power, wind power and combination of these. Three main types of EVs include:
Vehicles that are directly powered by an external source of power,
Vehicles that are run on the electricity stored by an external source, and
Vehicles that are powered by an on-board electric generator
Based on these categories, electric vehicles includes four types namely BEV( Battery Electric Vehicles), PHEVs( Plug-in Hybrid Vehicles), HEVs( Hybrid Electric Vehicles), and Fuel-cell electric vehicles. A BEV runs entirely on the battery; it does not contain conventional Internal Combustion Engine( ICE). Batteries for these vehicles are charged by plugging into some external source. However, regenerative braking also facilitates the slow down the vehicle and recovers a tad of energy.
PHEVs are run into batteries that are recharged by plugging into the power grid. Unlike BEVs, these vehicles do have ICE that assists in recharging the battery and/or replacing the electric drive train in situations of low battery. HEVs, typically, have an electric motor and a gasoline engine. As these cannot be recharged from the power grid, energy only comes from gasoline and regenerative braking.
Fuel-cell in another EVs that are expected to hit the market in next couple of years. Hyundai being the first to market a fuel-cell vehicle, many other( e.g. Toyota) are on the line to follow the suit. Fuel-cell vehicles generate electricity from oxygen and hydrogen. These are high in efficiency and emit only water, experts have conceded these cars the best among all EVs. However, the development is still in embryonic stages as fuel-cell cars are not free of shortcomings. Extracting hydrogen from the water molecule is an energy-intensive process that is responsible for generating GHGs.
While EVs include a gamut of road and rail vehicles, underwater and surface vehicles, and electric spacecraft and aircraft, the general public is unaware of these variations and most of the people equate EV with just electric cars. However, the situation might change in next couple of years as the world is witnessing a growing obsession towards these automobiles. Government policies have also decided that ten percent of vehicles will be powered by electricity by 2020.
Their high energy efficiency is what makes them the most plausible option in the future. Additionally, these vehicles are capable of converting around 60 percent of electrical energy to power at the vehicle, compared to poor 17-21 percent conversion by their conventional counterparts. Negligible emission of tailpipe pollutants is an icing on the cake. All in all, they provide a smooth and 'quiet' experience to the drivers as well as passengers. On a negative note, there is a slew of battery-related issues ranging from the high cost of batteries, recharge time, low driving range, and the bulkiness of batteries. Further research and development in the coming years are expected to explore feasible solutions to these problems.
References
Sustainable Energy Authority of Ireland. (2015). seai.ie. Retrieved September 8, 2016, from A Guide to Electric Vehicles: http://www.seai.ie/Your_Business/Technology/Industry/Electric_Vehicles.pdf
U.S. Department of Energy. (2015). fueleconomy.org. Retrieved September 8, 2016, from www.fueleconomy.org: https://www.fueleconomy.gov/feg/evtech.shtml
