What Is a Hybrid Car & How Do They Work?
In the simplest terms, a hybrid car uses more than one kind of energy (or hybridizes its energy sources) to generate its propulsion. The most prominent combination of energy in a hybrid vehicle is that of gasoline, via an internal combustion engine (ICE, also sometimes referred to simply as a “gasoline engine”), and electricity, via an electric motor, although other energy combinations do currently exist, albeit predominantly outside of the North American market.
The biggest advantage of driving any type of hybrid vehicle — and there are several types — is that hybrid cars can use the most efficient blend of energy sources to maximize fuel economy across driving conditions, without a major penalty to performance. There are, of course, additional benefits, not least of which is a reduction in exhaust pipe emissions.
Let’s take a closer look at what makes a hybrid car a hybrid car, and how these types of vehicles work.
Types of hybrid cars and how they use energy
Full hybrid electric vehicle (HEV)
A full hybrid electric vehicle is the type of hybrid that most people think of when they hear the term applied to a car. A full hybrid uses a gasoline engine and one or more electric motors (electricity is supplied by a dedicated battery or battery pack) to propel the vehicle. Depending on the vehicle’s design, the hybrid vehicle battery pack can be charged by the gasoline engine and/or via regenerative braking — meaning gasoline continues to be the only “energy” or “fuel” you ever add to an HEV.
The engine and motor(s) run independently or together based on driving and vehicle conditions such as load, accelerator pedal position, temperature, battery state of charge, and so on. If equipped with all-wheel-drive, a hybrid vehicle may also use different power sources to drive the different axles of your car. For example, the vehicle might use its gasoline engine to drive the front wheels and the electric motor to drive the rear wheels separately.
Mild hybrid (MHEV)
A mild hybrid works like a full hybrid, but on a smaller scale. The name generally applies to hybrid vehicles that use the electric motor(s) to support the gasoline engine, which provides primary propulsion power. The electric motor cannot independently power the vehicle, but it does reduce the load on the gasoline engine in certain driving situations and provides energy to help run accessories like climate control, power steering, and so on. Some mild hybrid vehicles also feature idle stop, a technology that will stop the engine when the vehicle is stationary and use the electric motor to automatically restart the vehicle when it’s ready to move on. An MHEV’s electric motor may also provide a power boost when driving in the under 30 mph range.
What about plug-in hybrids? (PHEV)
A plug-in hybrid vehicle is a hybrid vehicle but has a more substantial battery pack and motor(s) that can drive the vehicle independently of the gasoline engine. Typical PHEVs have the ability to drive longer distances on electric power alone (15-60 miles, depending on the make and model of the vehicle).
While PHEV vehicles benefit from onboard charging from the gasoline engine and regenerative braking, a PHEV is also designed to be plugged in and charged through an external charging system. If you have a commute or schoolyard Grand Prix within the range limits noted above and reliable access to Level 1 or Level 2 charging, you shouldn’t need to put any gasoline in your PHEV’s tank for weeks or potentially months.
Conversely, if you take a long trip, you won't face range or recharging anxiety, because all PHEVs will switch to gas-powered driving once the battery runs out of charge. When a PHEV battery pack’s state of charge (SOC) becomes too low to power the electric motor, it will operate like a traditional vehicle with a gasoline engine. Just keep in mind that if you don’t charge your PHEV, you’re still carrying around extra weight in the form of the vehicle’s battery; if you don’t have good charger access or routinely travel longer distances, a full hybrid may be a more suitable option for your needs.
What’s the difference between parallel hybrid vehicles and series hybrid vehicles?
In a parallel hybrid vehicle, the internal combustion engine and electric motor(s) are both independently capable of delivering propulsion that will drive the vehicle’s wheels. Or act together when needed for maximum power.
In a series hybrid vehicle, the electric motor(s) drive the wheels, while the gasoline engine is used solely for charging the battery pack that stores electricity for the electric motor(s). Series hybrids generally have a descriptor like “range extender” in the name.
How do hybrid cars work?
Let’s focus here on full hybrid electric vehicles. These cars have an engine under the hood, a conventional fuel tank, one or more electric motors, and a battery pack, which is typically located beneath the rear seat or cargo area.
The battery pack is charged by the engine, which frequently has more power available than is needed by the car. It is also charged by regenerative braking, a process in which kinetic energy can be captured while braking and converted into electricity. This electric energy is then stored in the hybrid battery pack.
Since electric motors produce excellent torque from a full stop, a smaller gasoline engine can be used in a hybrid vehicle, with the combined hybrid power delivering the same performance as a similarly sized ICE vehicle. HEV owners typically enjoy fuel savings because of this smaller engine and because the electric motor can reduce the load on the engine.
Important components of HEVs
Considering weight, cost, and significance, the most important parts found in an HEV include:
● Battery pack: The battery pack supplies electrical energy to an HEV’s motor(s). It is often referred to as the traction battery to differentiate it from the conventional 12-volt battery in vehicles. These traction battery packs are usually warranted for approximately 8 years/100,000 miles.
● Traction motor(s): These are the electric motors that move the car and recover energy via regenerative braking. Their power is typically listed as kilowatts (kW) or horsepower (hp) in the specifications, and they are often referred to as a motor/generator unit. A hybrid may have other or unique motors for accessories’ drives, automatic start/stop, and so on.
● Electronics controller: This is the electronic brain that manages the flow of electricity during power and regeneration, the gasoline engine, and how the two propulsion sources interact.
● Ancillaries: Some hybrids use a different instrument panel and display options within that panel. A hybrid’s cooling systems are often upgraded.
● PHEV charging port: All PHEVs have a charging port, although its type and where it’s located are make and model-specific.
● PHEV thermal management: Because of its larger-capacity traction battery, a PHEV cooling/heating system will be more complex, have higher capacity, or both.
Fact checks: Do hybrid cars need gas? Or charging?
Every hybrid vehicle, including PHEV, requires fuel for its internal combustion engine. Typically, gasoline, but there are a few diesel-powered hybrid vehicles. Electricity for the hybrid battery pack can be generated on board via regenerative braking or from the engine itself. And while you technically don’t need to use a plug-in hybrid’s external electric charging capabilities, as it’s built to function well on gasoline alone, if you do not regularly charge your PHEV, you’re missing out on its signifying attribute and using more fuel than necessary.
Benefits of hybrid vehicles
2.Hybrids are urban-friendly. Not only is a hybrid’s advantage in fuel economy and from-stop performance greater in the city, but their emissions are lower compared to similarly sized gas-powered vehicles driving in the city as well.
3. Hybrids are relatively reliable. While Consumer Reports found PHEV and EV reliability are manufacturer-dependent, hybrids were described as “extremely reliable.”
4. Hybrids typically do well at resale. Even buyers of certified pre-owned vehicles seek low fuel consumption and reliability.
5. Hybrids may require less maintenance than non-hybrids. Driven efficiently, a hybrid may get measurably longer life from its brake wear components, and the engine is not usually worked as hard as it is in a non-hybrid vehicle. You can learn more in our article on EV maintenance.
Is a hybrid vehicle right for you?
A hybrid vehicle works well for essentially all driving scenarios, whether you, your family and friends road trip cross-continent, you mostly spend your driving time on a quick commute, or anything in between. So, if you’re interested in better fuel efficiency, hybrid electric vehicles are a great place to start. And as mentioned, for certain owners, a plug-in hybrid may prove more beneficial.
To sort out which kind of powertrain should power your next car, check out these articles:
• Compare Vehicle Types: HEVs vs. PHEVs and HEVs vs. Gas-Powered Vehicles
• Buyers’ Guides: Guide to Buying a HEV, Guide to Buying Any Type of EV , Should I Buy a HEV?
Explore Mazda HEVs and PHEVs
As part of our growing suite of electrified options, Mazda offers both two-row SUVs in the CX-50 Hybrid and CX-70 PHEV, as well as the three-row, CX-90 PHEV. All our electrified vehicles blend fuel efficiency with the Mazda well-known style and dynamic responsiveness.
Ready to experience a Mazda for yourself? Visit a Mazda Dealer near you and take any of our vehicles for a test drive today. Or if you’re thinking of expanding your fleet of fun, driver-focused Mazda vehicles, build your new Mazda online today.
This article is intended for general informational purposes only and is based on the latest competitive information available at the time of posting. Information herein is subject to change without notice and without Mazda incurring any obligations. Please review a variety of resources prior to making a purchasing decision. Visit Resource Center for more articles.