Hybrid Electric Vehicles - Cleaner & Healthier Alternatives?

This article was updated on the 19th August 2019.

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Hybrid vehicles are any vehicle which uses two or more sources of power. Hybrid electric vehicles (HEVs) combine the power from an internal combustion engine of a conventional vehicle with the battery and electric motor from an electric vehicle.

The use of an electric propulsion system in HEVs allows a smaller and lighter engine to be used, which, combined with energy storage in the vehicle’s battery and energy recapturing technologies such as regenerative braking, results in improved fuel economy and lower emissions from HEVs compared with conventional vehicles.

What are the Advantages of Hybrid Electric Vehicles?

HEVs offer several advantages over conventional vehicles. Greater operating efficiency can be achieved due to their use of smaller internal combustion engines resulting in less internal energy loss.

HEVs utilize regenerative braking, which recaptures the energy that is lost in heat when conventional vehicles brake. This recaptured energy can be stored in the HEV’s battery, and its benefit is especially noticeable during the stop-start driving cycle of modern city traffic.

HEVs consume less fuel than conventional vehicles using internal combustion engines while maintaining similar performance levels. This improved fuel efficiency reduces costs as well as the amount of harmful gases released from the tailpipe. Improved fuel efficiency also gives HEVs greater range than similar-sized conventional vehicles.

HEVs can utilize other efficiency-improving technologies. Start-stop technology switches the vehicle’s engine off when it is idle, reducing unnecessary energy consumption. Similarly, HEVs commonly only power the air conditioning unit, power steering and other electric pumps when needed, while conventional vehicles rely on inefficiently driving them continuously using engine belts.

Finally, HEVs designed for fuel efficiency commonly employ energy-saving techniques like improved aerodynamics and rolling resistance tires to maximize the fuel efficiency achieved through the use of battery storage and electric power generation.

Parallel hybrids use the electrical motor for idling and accelerating to low speeds, at which point the gasoline engine automatically begins combining power with the electrical motor.

Electrical engine assistance HEVs, however, use the gasoline engine for idling and low-speed driving while the electric motor provides additional power for acceleration or climbing hills. In this type of HEV, the gasoline engine is also employed to drive recharge the battery during normal travel.

What is a PHEV and How Does it Work?

A PHEV or a plug-in hybrid electric vehicle is similar to a hybrid electric vehicle, which is part electric vehicle and part conventional gasoline vehicle. The main difference between a PHEV and the hybrid electric vehicles is the way the battery is charged.

A PHEV has a larger battery that can be fully charged by plugging into a standard electrical outlet for a few hours each day. PHEVs can further reduce the usage of fuel by employing electrical energy captured through daily charging.

While the PHEV technology shows promise, a large number of energy and environmental issues must be considered before PHEVs become widely available. For example, while PHEVs might cost less to drive than a gasoline-powered vehicle, they would draw power from the electrical grid when charging.

The energy needed to extract and transport the coal, as well as the environmental considerations associated with burning the coal, are all part of the overall cost of using plug-in technology. These issues could decrease in importance as the amount of renewable energy in the electricity mix increases.