What is a Hybrid Car and How Do They Work?

If you’ve not bought a car in a while, you may be amazed and slightly confused at how things have changed. With eco-friendly driving and low emissions a key focus, the rapid arrival of hybrid and electric cars onto New Zealand roads have made car buying considerably more complicated.

Hybrid technology is not that new with vehicles having been around in Europe for some time, due to their higher emission standards. With the introduction of New Zealand’s equivalent through the Clean Car Discount programme, Kiwis are seeing more and more vehicles with hybrid and EV technology introduced on our roads. 

So, let’s take a look at what hybrid cars are, how they work and how they differ from traditional petrol cars, including the benefits and the things you should take note of when considering your next car purchase. 

How do hybrid cars work?

Hybrid cars are literally that — a hybrid or a combination of a traditional petrol car with electric vehicle technology. They combine the benefits of both petrol and electric propulsion, using a combination of a petrol engine, a battery, and an electric motor.

One key feature that sets hybrids apart is their regenerative braking system. This system captures momentum to create electricity as the car slows down or coasts, unlike regular cars that create friction and waste energy as heat. 

Let’s break down the main elements of a hybrid system:

The internal combustion engine in a hybrid car has two main purposes. First, it powers the car when needed, just like in a traditional petrol car. Second, it can also recharge the battery by generating electricity while it runs. This ensures that the battery has enough energy to power the electric motor when required.

The electric motor in a hybrid car works in tandem with the petrol engine to power the car. It can assist the petrol engine during acceleration, providing an extra boost of power. In certain models, it can also take over completely when driving at lower speeds or in stop-and-go traffic, running solely on electric power. This improves fuel efficiency and reduces emissions, especially in city driving conditions.

The battery in a hybrid car stores the energy generated by the petrol engine and regenerative braking. It then uses this stored energy to power the electric motor, which assists the petrol engine to propel the car and other electrical systems in the car such as air conditioning and window wipers. The batteries are made of lithium and are designed to be recharged while you’re driving, through the energy generated by the petrol engine and regenerative braking, ensuring a continuous supply of power for the electric functions.

Regenerative braking is a unique feature of hybrid cars that captures energy that would normally be lost during braking, and stores it in the battery for later. When the driver applies the brakes, the electric motor acts as a generator converting the kinetic energy of the moving car into electricity, which is then fed back into the battery. This process not only helps to recharge the battery, but also improves the overall efficiency of the car, as the captured energy is used instead of being wasted as heat.

Different types of hybrid cars

Plug-In Hybrids

PHEVs (Plug-in Hybrid Electric Vehicles) have a large battery capacity and can be charged through an external power source, like an electric outlet or charging station. This allows for extended all-electric driving range, with the ability to operate only using electric power for a certain distance before the petrol engine kicks in. PHEVs are ideal for those who have access to charging infrastructure and want the flexibility of both electric and petrol-powered driving.

Full Hybrids

HEVs (Hybrid Electric Vehicles) have a smaller battery capacity compared to plug-in hybrids and can’t be charged through an external power source. Instead, they rely on regenerative braking and the petrol engine to charge the battery. 

Full hybrids have the ability to operate either only on the petrol engine, or on the electric motor, or a combination of both, depending on the driving conditions and battery charge level. This option is a bit more flexible and uses a great balance of both petrol and electric power, which improves fuel-efficiency and reduces emissions.

Self-Start Hybrids (Mild Hybrids)

Self-start hybrids, also known as mild hybrids, have a smaller and less powerful electric motor compared to full hybrids. They typically don’t have the ability to operate only using electric power, instead using the electric motor to help the petrol engine during acceleration. Mild hybrids like the Swift or Vitara Hybrid, also have the ability to start the petrol engine using the electric motor, which helps to reduce fuel consumption and emissions. This is especially helpful during stop-and-go driving conditions, such as waiting at the traffic lights.

Parallel and Series Hybrids

These are two different configurations of hybrid powertrains. In a parallel hybrid, both the petrol engine and the electric motor can power the car simultaneously, providing additional power when needed. In a series hybrid, the petrol engine acts as a generator to charge the battery, which then powers the electric motor that drives the wheels. Each configuration has its advantages and disadvantages in terms of efficiency, power delivery, and complexity.

The benefits of hybrid cars

Here are some of the benefits you will find when owning and driving a hybrid car:

Improved fuel economy — hybrid cars of a similar specification have better fuel economy than traditional petrol cars, resulting in reduced fuel consumption and lower fuel costs over time.

Reduced emissions — by using less fuel hybrid cars produce fewer CO2 emissions compared to petrol cars, resulting in lower greenhouse gas emissions and a positive impact on the environment by reducing air pollution and mitigating climate change.

Rebate incentives — some hybrid cars may be eligible for the Government’s Clean Car rebate and others may avoid Clean Car fees, making them more affordable for consumers by offsetting some of the initial purchase cost.

Quieter and smoother driving experience — depending on their set-up, some hybrid cars provide a quieter and smoother driving experience compared to traditional petrol cars. Their silent operation and instant torque from the electric motor, result in reduced noise pollution and a more comfortable ride.

Peace of mind — driving a hybrid car, as opposed to an EV, means you have the added security of knowing you won’t get caught stranded if your car runs out of charge. A hybrid vehicle has the ability to fall back on its petrol powertrain when you need it.

The drawbacks of hybrid cars

When looking at purchase a hybrid vehicle, there are some things you should keep in mind:

Higher upfront cost — hybrid cars can sometimes have a higher upfront cost compared to traditional petrol cars, due to the additional technology and components required for their hybrid system. Depending on the initial price, this cost can usually be offset by potential fuel savings over time.

Limited electric range — Plug-in hybrid cars may have a limited electric range, depending on the size of the battery and the model, meaning more frequent use of the petrol engine for longer trips. Recharging at home or at public charging stations can help maximise the electric driving range, as long as you are organised and remember to plug-in. 

In a nutshell, hybrid cars have plenty of advantages, including better fuel economy, lower emissions, potential cost incentives, and a smoother driving experience. 

Ready to explore hybrid cars further? Download our Guide to Buying a New Car to get all the information you need for your next eco-friendly ride!