Explaining Electric and Plug-In Hybrid Electric Vehicles
Electric vehicles (EVs) have a battery instead of a gasoline tank, and an electric motor instead of an internal combustion engine. Plug-in hybrid electric vehicles (PHEVs) are a combination of gasoline and electric vehicles, so they have a battery, an electric motor, a gasoline tank, and an internal combustion engine. PHEVs use both gasoline and electricity as fuel sources. More on PHEVs.
Watch the video to learn how electric vehicles and different types of plug-in hybrid electric vehicles work.
EVs and PHEVs are now available in multiple vehicle classes. There are currently over 50 EV and PHEV models on the market, and more models are expected to be released in the coming years. Visit fueleconomy.gov for a full list of options. Not all models are available in all 50 states.
EVs produce no tailpipe emissions. While charging the battery may increase pollution at the power plant, total emissions associated with driving EVs are still typically less than those for gasoline cars—particularly if the electricity is generated from renewable energy sources like wind.
PHEVs produce tailpipe emissions when gasoline is being used as a fuel source.
To estimate the greenhouse gas emissions associated with charging and driving an electric or plug-in hybrid electric vehicle where you live, visit our Greenhouse Gas Emissions for EVs and PHEVs Calculator.
The number of miles an EV will travel before the battery needs to be recharged is often less than the distance your gasoline car can travel before being refueled, but typically is still enough to accomplish the average person’s daily driving needs. An electric vehicle’s fuel economy is reported in terms of miles per gallon of gasoline-equivalent (MPGe). Think of this as being similar to MPG, but instead of presenting miles per gallon of the vehicle’s fuel type, it represents the number of miles the vehicle can go using a quantity of electricity with the same energy content as a gallon of gasoline. This allows you to compare an EV with a gasoline vehicle even though electricity is not dispensed or burned in terms of gallons.
PHEVs typically have driving ranges that are comparable to gasoline vehicles. PHEVs have two fuel economy values: one for when the vehicle operates primarily on electricity (listed in terms of MPGe), and one for when the vehicle operates only on gasoline (listed as MPG).
Note: The EPA estimates, including EV range, are meant to be a general guideline for consumers when comparing vehicles. Just like “your mileage may vary” for gasoline vehicles, your range will vary for EVs. In particular, factors like cold weather, accessory use (such as A/C), and high-speed driving can lower your vehicle’s range significantly.
Visit www.energy.gov to get tips on maximizing your electric car’s range in extreme temperatures.
Depending on how far you drive each day, you may be able to meet all your driving needs by plugging in while at home. Most EVs can be charged with a standard 120 V outlet. To charge the vehicle more quickly, you may want to install a dedicated 240 V outlet or charging system. You may also be able to plug in at your workplace, or at one of the growing numbers of public charging stations.
- Learn more about EV charging
- Learn more about charging equipment
- ENERGY STAR certified EV charging equipment
- Public charging stations
Plug-in hybrids, sometimes called Plug-in Hybrid-Electric Vehicles (PHEVs), are hybrids with high-capacity batteries that can be charged by plugging them into an electrical outlet or charging station. They can store enough electricity to significantly reduce their petroleum use under typical driving conditions.
Different Kinds of Plug-in Hybrids
There are two basic plug-in hybrid configurations:
Series plug-in hybrids, also called Extended Range Electric Vehicles (EREVs). Only the electric motor turns the wheels. The gasoline engine only generates electricity. Series plug-ins can run solely on electricity until the battery runs down. The gasoline engine then generates electricity to power the electric motor. For short trips, these vehicles might use no gasoline at all.
Parallel or Blended Plug-in Hybrids. Both the engine and electric motor are connected to the wheels and propel the vehicle under most driving conditions. Electric-only operation usually occurs only at low speeds.
Some plug-in hybrids have higher-capacity batteries and can go further on electricity than others. PHEV fuel economy can be sensitive to driving style, driving conditions, and accessory use.
Benefits and Challenges
Less Petroleum Use. Plug-in hybrids use roughly 30% to 60% less petroleum than conventional vehicles. Since electricity is produced mostly from domestic resources, plug-in hybrids reduce oil dependence.
Less Greenhouse Gas Emissions. Plug-in hybrids typically emit less greenhouse gas than conventional vehicles. However, the amount generated depends partly on how the electricity is produced. For example, nuclear and hydroelectric plants are cleaner than coal-fired power plants.
Higher Vehicle Costs, Lower Fuel Costs. A plug-in hybrid can cost roughly $4 to $8 thousand more than a comparable non-plug-in hybrid. Using electricity is usually cheaper than using gasoline, sometimes much cheaper. However, fuel savings may or may not offset the higher vehicle cost. It depends on the vehicle, the share of miles operating on electricity, fuel costs, and ownership length. Federal tax incentives up to $7,500 are currently available for qualifying plug-ins.
Re-charging Takes Time. Re-charging using a 120-volt household outlet can take several hours. Re-charging using a 240-volt home or public charger can take about 1 to 4 hours. A "fast charge" to 80% capacity may take as little as 30 minutes. However, these vehicles don't have to be plugged in. They can be fueled solely with gasoline but will not achieve maximum range or fuel economy without charging.
Estimating Fuel Economy. Since a plug-in can operate on electricity alone, gasoline alone, or a mixture of the two, EPA provides a fuel economy estimate for gasoline-only operation and an estimate for electric-only or gas-and-electric operation—both for combined city-highway driving.
Some PHEVs operate exclusively, or almost exclusively, on electricity until the battery is nearly empty. Then, gasoline is burned in the engine to provide additional power. Other PHEVs—sometimes called “blended mode” PHEVs—use gasoline and electricity together to power the vehicle while the battery has charge.
- The Department of Energy My Plug-in Hybrid Calculator and
The University of California, Davis EV Explorercan help you determine if a PHEV is right for you. Compare different vehicles to get yearly fuel costs customized to your commute, frequency of travel, and charger access.