Hybrid Cars Explained

Hybrid Cars Explained in Plain English – How Do They Actually Work?

Over the past few months, I’ve had quite a few customers asking me about hybrid cars.

Some are thinking about buying one. Others already own one but aren’t entirely sure how the technology works.

If I’m completely honest, I understood the basic idea myself, but if someone had asked me to explain it properly a few weeks ago, I might have struggled.

That all changed when I bought my own Hyundai Tucson Self-Charging Hybrid.

Like many motorists, I was curious.

How does it know when to use petrol?

Where does the electricity come from?

Do you ever have to plug it in?

Is it really saving fuel?

So, I decided to learn more. Rather than filling this article with complicated engineering terms, I thought I’d explain hybrid cars in the same way I’d explain them to one of our customers over a cup of tea in the reception at Pellon Tyres.

What Is a Hybrid Car? Hybrid Cars Explained

The word hybrid simply means a combination of two different things working together.

In a hybrid car, those two things are:

a petrol engine
an electric motor

Instead of relying entirely on petrol like traditional cars, a hybrid uses both power sources to make driving more economical and reduce emissions.

The clever bit is that the car decides which one to use.

You don’t have to press any buttons or flick any switches.

It does all the thinking for you.

There Are Three Main Types

One thing that confuses many people is that not all hybrid cars are the same.

There are actually three main types available today.

Mild Hybrid (MHEV)
Self-Charging Hybrid (HEV)
Plug-in Hybrid (PHEV)

Each works slightly differently.

Mild Hybrid – Think of It as a Helpful Assistant: Hybrid Cars Explained

The easiest way to understand a mild hybrid is to imagine someone helping you push a heavy wheelbarrow.

You’re still doing nearly all of the work yourself.

They’re simply giving you a little extra shove.

That’s exactly what happens in a mild hybrid.

The petrol engine still provides almost all of the power.

The small electric motor simply helps during situations such as:

pulling away
accelerating
climbing hills
restarting the engine after stopping

The electric motor cannot normally drive the car on its own.

Instead, it gives the petrol engine a helping hand whenever extra effort is needed.

This saves fuel because the petrol engine doesn’t have to work quite as hard.

Self-Charging Hybrid – Two Engines Working Together

This is the type I now drive.

My Hyundai Tucson is a Self-Charging Hybrid.

Many Toyota, Lexus, Honda, Kia and Hyundai models also use this system.

This is where things become really clever.

Instead of simply helping the petrol engine, the electric motor can actually drive the vehicle by itself under certain conditions.

Imagine two cyclists riding a tandem bicycle.

Sometimes one rider does most of the work.

Sometimes the other rider takes over.

Sometimes they both pedal together.

That’s exactly how a self-charging hybrid works.

The onboard computer constantly decides which power source is the most efficient.

It might use:

just the electric motor
just the petrol engine
both together

The driver doesn’t have to think about it.

How Does It Know Which Engine to Use? Hybrid Cars Explained

This amazed me when I first started driving the Tucson.

If I’m gently driving through traffic or moving around a supermarket car park, it often uses only the electric motor.

The car becomes almost silent.

As soon as I accelerate harder or join a faster road, the petrol engine quietly starts and helps out.

Sometimes you hardly notice it happening.

The computer is making hundreds of decisions every minute.

It constantly monitors:

road speed
battery charge
engine load
throttle position
outside conditions

It simply chooses whichever combination gives the best fuel economy.

But Where Does the Electricity Come From?

This is probably the question I hear most often.

People assume someone must plug the car in every evening.

Not with a self-charging hybrid.

The electricity is produced while you’re driving.

Regenerative Braking: Hybrid Cars Explained

This sounds complicated.

It really isn’t.

Think about riding a bicycle down a hill.

Normally, if you squeeze the brakes, all of that movement is wasted as heat.

A hybrid car is much cleverer.

Instead of wasting all that energy, the electric motor works like a generator.

As you slow down or brake, it captures some of the energy that would otherwise disappear.

That energy is converted into electricity.

The electricity is stored in the hybrid battery.

It is then ready to help drive the car later.

You’re effectively recycling energy that would normally be lost.

It’s a wonderfully clever idea.

The Petrol Engine Also Helps

Sometimes the battery needs topping up.

When that happens, the petrol engine can also produce electricity.

Again, the computer decides when this needs to happen.

As the driver, you simply carry on driving normally.

Do You Ever Need to Plug It In? Hybrid Cars Explained

Not with a self-charging hybrid.

That’s one of the reasons I chose mine.

There are:

no charging cables
no wall box
no searching for charging points

You simply fill it with petrol exactly as you always have.

The car looks after the battery itself.

Plug-in Hybrids

A plug-in hybrid is slightly different.

Think of it as a self-charging hybrid that’s been given a much larger battery.

Because the battery is much bigger, it can power the car for many more miles using electricity alone.

Typically, many modern plug-in hybrids can travel between 30 and 60 miles before the petrol engine is needed.

To achieve that, you plug the car into a charging point at home or at a public charger.

Once the battery becomes low, the car behaves very much like a normal self-charging hybrid.

Which Type Saves the Most Fuel? Hybrid Cars Explained

That depends entirely on how you drive.

A mild hybrid gives modest fuel savings.

A self-charging hybrid works brilliantly for motorists who spend time in towns and cities because there’s lots of slowing down and braking, allowing the battery to recharge regularly.

A plug-in hybrid can be incredibly economical if your daily journeys are short enough to stay mostly on electric power.

However, if you rarely charge it, much of its advantage disappears.

What Happens on the Motorway?

Many people think hybrids are only useful around town.

That’s not true.

On faster roads, the petrol engine usually does most of the work because it’s more efficient at steady motorway speeds.

However, the electric motor is still ready to help during acceleration or overtaking.

The two systems continue working together.

Is the Battery Always Running Flat?

No.

This surprised me too.

The car never allows the battery to become completely empty or completely full.

Instead, it keeps the battery operating within its ideal range.

That’s one reason hybrid batteries often last for many years.

Are Hybrid Cars Reliable? Hybrid Cars Explained

From everything I’ve seen, modern hybrids have earned an excellent reputation.

Manufacturers have now been producing them for well over twenty years.

Many hybrid taxis have covered enormous mileages with very few problems.

Like any vehicle, they still require servicing, tyres, brakes, suspension work and MOT testing.

They’re not maintenance-free.

They’re simply different.

My Own Thoughts

Since buying my Hyundai Tucson Hybrid, I’ve become a genuine fan of the technology.

What I like most is its simplicity.

I don’t have to change the way I drive.

I don’t have to worry about charging cables.

I don’t have to think about when to switch between petrol and electric.

The car quietly does all of that for me.

As someone who’s spent most of his life around motor vehicles, I have to admit that it’s rather impressive.

The Future Is Already Here

Whether we like it or not, the motor industry is changing.

Hybrid cars are becoming an increasingly common sight on the roads around Halifax, Calderdale and West Yorkshire.

Many families are discovering they offer an excellent balance between traditional petrol motoring and fully electric vehicles.

For many drivers, especially those who aren’t quite ready to make the jump to a fully electric car, a hybrid provides the perfect stepping stone.

Final Thoughts: Hybrid Cars Explained

If someone now asks me how a hybrid works, my answer is much simpler than it used to be.

Imagine having two engines that work together like two experienced workmates.

One uses petrol.

One uses electricity.

A clever computer decides which one should do the hard work at any given moment.

The electricity isn’t wasted or magically created—it is largely recovered every time you slow down or brake, then stored ready to help the next time you accelerate.

Once you understand that simple principle, the whole idea of a hybrid suddenly makes perfect sense.

After spending a little time with my own self-charging hybrid, I can certainly understand why so many motorists are making the change.

Hybrid Cars Explained