Electric Vehicle Basics
For the purposes of this discussion, an electric vehicle is one with a battery that can be charged by plugging the car into an electrical outlet or charging unit. Energy stored in the battery is then used to power an electric motor that propels the car down the road for a certain distance without the use of a gasoline engine. These types of vehicles are sometimes referred to generically as Plug-in Electric Vehicles (PEVs). There are three basic types of electric vehicles:
- Plug-in Hybrid Electric Vehicles (PHEV)
- Extended-Range Electric Vehicles (EREV)
- Battery Electric Vehicles (BEV)
A plug-in hybrid electric vehicle is similar to a conventional hybrid automobile, but has a larger battery that can be charged by plugging into an electric outlet. PHEVs typically have an electric-only range of 10 to 40 miles. Once that range is exhausted, the vehicle reverts to normal hybrid operation using a gasoline engine that drives the car and recharges the battery for limited electrical power assist. The Toyota Prius plug-in hybrid is an example of a PHEV.
An extended-range electric vehicle has a battery that typically provides a driving range of 30 to 40 miles. Once the battery has discharged, a gasoline-driven generator operates to power the vehicle for 300-plus miles of additional ‘extended-range’ driving. Unlike a PHEV, the gasoline engine does not actually drive the vehicle; it only provides power to the battery which continues to propel the car using an electric motor. The Chevrolet Volt is an example of an EREV.
A battery electric vehicle does away with the gasoline engine altogether and is powered entirely by electricity stored in a relatively large onboard battery pack. Most current BEVs have a range somewhere between 80 and 120 miles. The Nissan Leaf is an example of a BEV.
In many ways, electric vehicles are similar to conventional cars powered by internal-combustion engines. They meet or exceed the same safety standards, they have similar cargo and passenger space, and they are practical for both everyday commuting and (with appropriate charging support for BEVs) long-distance driving.
However, electric motors provide their maximum torque at zero rpm, which means EVs tend to accelerate quickly – and very quietly – from a stop. They are also highly efficient and very “smart.” Sophisticated in-vehicle instrument panels give EV drivers more information and controls than are available on conventional vehicles. In addition, some EVs have complementary smartphone apps that allow remote control of vehicle battery charging and other functions. Most electric vehicles also have a regenerative braking system that captures and restores energy to the battery as the car is brought to a stop. Finally, depending on the particular powertrain design, plug-in electric cars often require less maintenance than conventional vehicles.
That depends on the type of car you choose, the climate in which you live in, how you drive, and what opportunities are available to recharge the vehicle battery.
The typical commuter drives about 40 miles a day. Most EVs have an all-electric driving range of 10 to 120 miles before re-charging is required. This means that some or all of the average daily commute can be completed on electric power alone, depending on the type of EV being driven. Having the ability to recharge your car at work can increase the amount of all-electric driving, particularly with PHEVs which generally have the least battery capacity of the three EV types.
For many electric car owners, a total re-charge may not be necessary for daily driving. The nation’s network of EV charging stations continues to grow so, when necessary, motorists can often find charging options at work or in shopping areas.
How you drive also affects EV efficiency, performance and range. As with any car, gasoline or electric, the more aggressively you drive the more quickly your vehicle’s power supply becomes depleted. In addition, the use of accessories that draw electrical power (heating, air conditioning, defogging) will reduce the electric-only driving range of your EV.
Automakers are held to safety standards set by the Department of Transportation (DOT) and the National Highway Traffic Safety Administration (NHTSA). These standards apply to all vehicles, including plug-in electric models. To help maximize safety, EVs also meet various electrical and safety standards set by the National Fire Protection Association (NFPA), Society of Automotive Engineers (SAE), Underwriters Laboratories (UL), American National Standards Institute (ANSI), Code of Federal Regulations, National Electrical Code (NEC) and other relevant industry groups. In addition, electric vehicle charging equipment is tested and certified by independent organizations, such as Underwriters Laboratories, CSA International, and Edison Testing Laboratories.
Every vehicle comes with certain risks. In cars with internal combustion engines, a ruptured gasoline tank or fuel system can lead to a fire. However, EV manufacturers have done extensive research and testing to help ensure that the batteries and other powertrain components of electric vehicles are safe. Special systems are employed to manage battery temperatures and prevent overheating that could lead to a fire. In the event of a collision: the vehicle structure is designed to protect the battery, redundant fuses and circuit breakers will disconnect power, and the internal design of the battery itself isolates the individual cells to limit problems should physical damage occur.
To date, real-world experience with EVs has revealed nothing that would indicate EVs and their powertrains are any less safe than their internal combustion counterparts.
In early 2013, the most inexpensive electric car sold in the U.S. by a major automaker is the Mitsubishi iMiEV – a BEV with a list price of $29,100. The financial entry point for EVs is expected to drop even lower in the second quarter of the year when Mercedes-Benz will introduce an ED (Electric Drive) version of their Smart car with a base price of around $25,000. Nissan saw increased sales of the LEAF after a $6,000 price drop on the 2014 model manufactured in Tennessee where there are several PHEVs, EREVs and BEVs to choose from. Common models include the: Chevrolet Volt; Ford Focus EV, Fusion Energi and C-Max Energi; Nissan Leaf; and the Toyota Prius plug-in hybrid.
Two limited production high-end models reside at the top of the EV charts. Tesla leads the luxury end along with the new Cadillac ELR. Tesla Model S (BEV), which ranges from $52,400 to $72,400 depending on the size of the battery pack – and can cost thousands more when options are added.
The good news about EV prices is that almost no one pays retail. Governments and the private sector have taken a number of steps to encourage the sales of EVs. A Federal tax credit may apply and some states, provinces, and local governments also offer tax incentives for plug-in electric cars. Prospective EV buyers should thoroughly investigate any available incentives ahead of time, and determine whether they would qualify for and benefit from them.
Besides purchase tax credits, other benefits can come with EV ownership. Electric cars often are given access to High-Occupancy Vehicle (HOV) lanes on freeways, reducing commute times for the drivers of these fuel-efficient automobiles. Also, many utilities have “off-peak” electricity rates that allow plug-in car owners to recharge their batteries at the lowest possible rates – usually, at night. And let’s not overlook the “cool” factor of being the first in your circle of friends to drive the latest in automotive technology.
More incentives for electric vehicles are introduced almost every day. To keep current on what’s available where you live, go to the GoElectricDrive Resource Locator.
Numerous studies have shown that the existing grid can support a large number of EVs without the need for new sources of electrical power. Total capacity is not an issue; rather, utilities need to understand how to best forecast and manage local electrical distribution to accommodate the load requirements in neighborhoods and cities where there may be high concentrations of EVs. This process is not unlike the steps that were needed following the widespread adoption of high-load electrical appliances such as washers, dryers and air conditioning.
As part of their ongoing analysis of EVs impact on the power grid, the Electric Power Research Institute (EPRI) has developed models that will provide utilities with a means to predict potential problem areas so they can proactively implement energy-efficient solutions and ensure the reliability of their distribution systems. These predictive models will be updated regularly as the EV market continues to grow.