Simply put, a hybrid uses a gasoline engine and at least one electric motor to move the vehicle, and its system recovers energy while braking. Sometimes the gas engine and sometimes the electric motor operate in tandem to complete the task. As a result, less gasoline is consumed, improving fuel efficiency. In some circumstances, adding electric power can even improve performance.
With all of them, electricity is provided by a high-voltage battery pack (different from the vehicle's standard 12-volt battery) that is refilled by preserving kinetic energy during deceleration that is generally wasted to heat produced by the brakes in traditional vehicles. Hybrids also use the gas engine to charge and maintain the battery (through the regenerative braking system). Different hybrid designs are used by automakers for a variety of purposes, from maximizing fuel efficiency to minimizing vehicle costs.
Type of Hybrid Vehicles
The most popular system in use connects the gasoline engine and electric motor(s) in a single transmission that combines the two power sources. That transmission could be continuously variable, automatic, or manual (CVT). The size of the gasoline engine and the kind of transmission are the two key variables that affect how quickly, loudly, and smoothly a parallel hybrid accelerates.
There is never a direct mechanical link between the engine and the wheels in this system; all propulsion is provided by the electric motor(s). The purpose of the gasoline engine is only to replenish the battery. Because of this, the driving experience is more akin to that of an electric vehicle, with smoother, more potent acceleration. When a gasoline engine starts, vibration is normally reduced. The engine may be revving up when the automobile is driving at a steady speed since that engagement doesn't always occur in tandem with what your right foot is doing (remember, the battery is making the demands). Some people find this conduct unsettling.
With a significantly larger battery pack that, like an electric car's, needs to be fully recharged using an external power source—from your home, office, or public charging station—a plug-in hybrid improves on the conventional hybrid concept. This increased capacity for energy storage functions similarly to a bigger gas tank in that it permits longer all-electric ranges (between 15 and 55 miles, depending on the model) while also lowering fuel usage. In reality, if your commute is brief and you recharge every night, you'll be using electricity the majority of the day. If the all-electric range is used up, the vehicle essentially transforms back into a standard parallel hybrid.
Variations on the Hybrid Theme
The answer to the question "what is a hybrid?" has become more difficult as technology has advanced over the past 20 years. Honda's new hybrid design, for example, doesn't cleanly fit into the series or parallel bucket. In this configuration, the engine mostly drives a generator, similar to a series hybrid, but it can also drive the wheels directly at times, similar to a parallel hybrid. Then there are the so-called through-the-road hybrids, such as the Volvo plug-in hybrids, which have a front-wheel-drive engine and transmission that are pretty conventionally mated with an electrically powered rear axle.
All of the aforementioned vehicles are regarded as "complete hybrids," which indicates that the electric motor is able to propel the vehicle independently, even if just temporarily. It can't in a "mild" hybrid. Similar to a full hybrid, a mild hybrid has an electric motor that works with the gasoline engine to enhance either performance or fuel efficiency. It also acts as the starter for the fuel-saving automatic start-stop system, which turns off the engine when the vehicle comes to a halt.
Mild hybrids don't increase fuel efficiency to the same degree as full hybrid systems do, despite their original intention to be a simpler and less expensive way to market hybrid technology. As a result, they were never as well-liked. The use of 48-volt electrical subsystems, however, shows that mild hybrid powertrains are currently making a comeback. In essence, automobile manufacturers are already incorporating mild hybrid technology into nearly every new model. The answer to the question "what is a hybrid?" may be "everything" in the not-too-distant future.