Flexibility and low initial costs mean that motorized transport based on the internal-combustion engine (ICE), has come to dominate the markets for passenger and freight transportation across the globe. The recent rapid growth in the number of vehicles, together with the limited implementation of emission control technologies, have made ICEs the major source of urban air pollution in the developing world.
The large-scale introduction of electric vehicles is seen as a critical part of the solution to this problem of emissions. Electric engines produce no tailpipe carbon emissions and the energy they consume is increasingly being produced from renewable energy sources. Electric engines are also more efficient than ICEs and can help decrease energy use. Both features help to reduce the emissions from energy production.
In addition, electric vehicles can be plugged into the electric grid when not in use so they have the potential to become an important element in the Smart Grids being developed. These battery powered vehicles can be used to even out the demand for electricity by supplying energy to the grid from their batteries during peak use periods during the day while charging mostly at night, when there is unused generating capacity. This Vehicle to Grid (V2G) connection has the potential to reduce the requirements for new power plants.Types of Electric Vehicles (EVs)
An electric vehicle (EV) uses one or more electric motors for propulsion. There are currently three major types of electric vehicles:
- Those directly powered from an external power station via power lines, such as electric trains, trolley buses, and trolley trucks.
- Those powered originally from an external power source, but able to store electricity in batteries, flywheels or capacitors, such as electric cars and bikes.
- Those powered by an on-board electrical generator, such as hydrogen fuel cell for electric cars or nuclear reactors for submarines.
- Those that can be powered by an electric engine and an internal combustion engine, called hybrid electric vehicles.
The Pros and Cons
|Specific energy and specific power of different battery types - IEA|
Electric motors have several advantages over ICEs:
- Efficiency - Electric motors convert 75% of the chemical energy from the batteries to power the wheels while ICEs only convert 20% of the energy stored in gasoline
- Eco-friendly - EVs emit no exhaust pollutants and can use non-polluting electricity from renewable sources, such as hydro-, solar-, or wind-power
- Performance - Electric motors provide quiet, smooth operation and better acceleration. They also need less maintenance than ICEs.
However, EVs have serious battery-related issues:
- Driving range - Most current EVs can only travel 100–200 miles before recharging, while fossil-fuel vehicles can reach over 300 miles before needing to re-fuel.
- Recharge time - Fully recharging a battery pack can take from 4 to 8 hours. An 80% capacity "quick charge" can take 30 min.
- Cost - Large battery packs are expensive and may need replacing more than once.
- Size & weight - Battery packs are heavy and can take up considerable vehicle space.
Inside an Electric Car
At the heart of an electric car lies the combination of:
- The motor's controller
- The batteries
Electric cars can use AC or DC motors and controllers. DC installations are simpler and less expensive. But AC installations allow the use of almost any industrial three-phase AC motor, which can make finding a motor with the required size or power rating much easier. AC motors and controllers often have a regen feature so that the motor turns into a generator and delivers power back to the batteries during braking.
The controller takes the power from the batteries and delivers it to the motor. The accelerator pedal connects to a pair of potentiometers (variable resistors) which provide the signal that tells the controller how much power it must deliver.
EVs in India Today
In recent years the Indian Government and Automotive industry have implemented a number of initiatives to advance the use of electric vehicles. These include:
- The WAVE[i] is a road-trip of electric vehicles, covering over 2500 Kilometers of southern India. They will begin at Mumbai and stop at schools, colleges, malls, and other places of importance in major Indian cities such as Pune, Hyderabad, Bangalore, and Goa.
- The National Council for Electric Mobility (NCEM) was also formed which would have representation by various ministries to devise a holistic policy for promotion of electric vehicles in the country.
- Delhi has established charging ports in 50 of its sub-stations in the city. Bangalore, has also equipped parking spaces in malls and offices with charging points for electric cars.
- In the 2012-2013 budget, the Ministry of Heavy Industry proposed an incentive package of Rs 6,000 crore (about € 1.2 billion), with proposed full exemption from basic customs duty and a concessional rate of excise duty on imported batteries, to boost the manufacturing of electric and hybrid cars in India.
The Indian market for EVs is at an early stage, with the biggest increase in EV production being in the 2-wheeler market. Mahindra Reva is the main established player in the electric car space at the moment. Since its inception in 2001, the company has had total sales of 5,000 cars up to 2011, with nearly 50 per cent of those being domestic sales.
The government and industry realize that both the battery technology and charging infrastructure need to improve to meet the customers' expectations of range, recharging and affordability, before they will switch over to EV.
"It is estimated that India's fossil fuel dependency on other countries ranged from 70% to 82% in 2012. If we can have three lakh Electric Vehicles on the roads by 2020, including three-wheelers, cars, and scooters, this could result in a reduction of over 16 lakh metric tons of CO2, NOx and HC by 2020, savings of over Rs 3,700 crores in foreign exchange and significant health costs savings."[ii]
Due to its high urban congestion, large domestic market and low manufacturing and research and development costs, the potential for electric vehicles in India is enormous. The current combination of high fuel prices and government support is steadily increasing the demand for EVs in India. Within the next ten years, the worldwide EV industry is projected to grow over Rs. 45,000 crores (USD 10 billion.) However, further research needs to be done to develop batteries that can store energy using as little weight as gasoline does, and can be recharged as quickly as refilling a fuel tank to accelerate the use of Electric vehicles.
[i]WAVE India - Techfest
[ii]Industry Analysis Report of Automobile Industry - B.SANTHOSH KUMAR