What is a Hybrid?

If you're looking for a fuel-efficient and environmentally friendly drive, a hybrid car is a great choice for those who aren't ready to go fully electric. What are hybrid cars, what are their pros and cons and which one is right for you? Find out all you need to know in this article.

Volvo XC90 fuel

How do hybrid cars work?

A hybrid car combines the conventional power of a diesel or petrol engine with an electric motor and batteries. It’s engineered to give you far better efficiency without losing out on performance. There are three main types of hybrid cars: parallel or full hybrids, mild hybrids and plug-in hybrids (PHEVs). A fourth type of hybrid – called the range extender – is less widely available and only uses conventional fuel to generate electricity to charge the batteries, making it the closest hybrid to a fully electric vehicle.

The Toyota Prius was the first hybrid model to be sold in the UK and was launched in 2000 to rave reviews on its fuel-efficiency and low CO2 emissions. The technology has since become increasingly popular, with most manufacturers currently offering hybrid models as part of their range. There are now over three-quarters of a million hybrid cars on the streets of the UK.

What are the pros and cons?

When deciding on a hybrid, you’ll want to look into the pros and cons. Superior fuel efficiency is a definite plus, but it’s not always guaranteed with some models’ driving modes. Here are some of the benefits and drawbacks of owning a hybrid car:


  • Lower running costs and greater fuel efficiency, with lower car tax than petrol or diesel cars
  • More environmentally friendly with lower emissions
  • Flexibility and choice of power modes to adapt to driving conditions
  • Wide range of models available from compact city cars to SUVs and family saloons


  • The initial cost of a hybrid is still generally higher than traditional fuel-powered vehicles
  • Electric-only driving modes are less efficient than hybrid modes as they burn fuel to power the battery
  • Full or mild hybrids have small batteries and so they won’t cover many miles in electric-only mode
  • Hybrids can be heavier because of the weight of battery packs installed

What is a full hybrid car?

A full or parallel hybrid is the most common on the market and uses technology powers your car in three ways. You can drive directly with the petrol/diesel engine, with the electric motor, or use a combination of both to get the best performance when you drive. It offers the best of both worlds, allowing you to use petrol or diesel power alone – even if your battery’s out of juice.

Take the Toyota Prius, for example. When you pull away, you’ll use electric power alone until you reach 15 mph, and then the fuel-powered combustion engine will kick in to give you the extra power needed for faster acceleration. This makes it great for efficiency in heavy traffic and on city roads. The battery power gets regenerated while you’re driving, too, and whenever you use your brakes. This produces electricity that’s then stored in the battery for later use.

What is a mild hybrid car?

Models using a mild hybrid system still combine a combustion engine with petrol or diesel fuel and electric power. But unlike in a full hybrid car, the two cannot be used independently of one another in a mild hybrid. The electric motor is used purely to assist the combustion engine, usually with accelerating and maintaining higher speeds. Energy can be regained when braking, to be stored in the system’s batteries and used to smooth out stopping and starting. Mercedes and Audi offer a variety mild hybrid models, along with other manufacturers such as Volvo and Kia.

What is a plug-in hybrid (PHEV)?

PHEV stands for ‘plug-in hybrid electric vehicle’. As the name suggests, this type of hybrid can be plugged in to recharge its batteries, as well as using kinetic energy to recharge while you’re driving. Larger battery packs allow for a bigger electric-only range, which is usually around 30 miles per charge. This means you can have all the benefits of a fully electric vehicle on short journeys and the added convenience of using the combustion engine for longer journeys. BMW, Mercedes, Volvo, Toyota and Hyundai are just some of the manufacturers leading the charge on plug-in hybrid models.

What is a range extender hybrid?

In a range extender hybrid, you’re only using the conventional fuel engine to generate electricity that recharges the batteries – making it the closest hybrid to a fully electric car. The sole use of its small petrol engine is to help generate power for the electric motor, and this electric motor does the work of powering the car. The BMW i3 is the most well-known example of this type of hybrid. Overall, range extenders are becoming less popular as the battery range of standard electric cars improves, making the range extenders feel more obsolete.

Hybrid cars can increase your fuel efficiency and reduce your impact on the environment without sacrificing performance. From city cars to large family SUVs, the three main types of hybrid vehicle offer maximum flexibility to make the best use of electrical power and conventional engines. At least until electric cars up their range and performance across the board, hybrids seem like the way of the future.

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