What is a hybrid?

With increasing oil prices and the cost of pollution becoming ever more apparent, governments and vehicle manufacturers are determined to make cars as efficient and eco-friendly as possible. Some refine existing petrol and diesel engine designs to the full, others choose to make use of hybrid technology.

By combining a conventional combustion engine with an electric motor, companies are able to create cars with astounding mpg figures and low emissions yet ones that also have enough power to cope with modern traffic. Here’s a guide explaining exactly how they work.

What is a hybrid?

Put simply, a hybrid is a car with more than one source of power. In most cases, you’ll find a petrol or diesel engine working in conjunction with one or more electric motors. Hybrids are a halfway-house between the range of a combustion engine and emission-free electric motoring – you get the best of both worlds.

The electric components in a hybrid use energy to help push the car along, but can also recapture otherwise wasted energy when you slow or brake. This recaptured energy is stored in a battery pack to be used once you accelerate again. Some hybrids have modes to help you manage the power effectively – saving battery power for crawling around the city while using the combustion engine at higher speeds.

How does hybrid technology work?

Exactly how the two power sources work together depends on the manufacturer. While they all have different ways of blending the two, the basic idea remains the same – when conditions allow, electric motors will replace or work with the combustion engine to provide forward thrust. The reduced load on the engine means it uses much less fuel.

What types of hybrid exist?

There are lots of hybrids on the market but, at the moment, there are two distinct types you can choose from…

Conventional hybrids

In conventional hybrids, the electric motor works on its own at lower speeds. This means, if you’re stuck in an untimely traffic jam or pottering around town, you’ll be using no fuel whatsoever. When you pick up speed though, the petrol or diesel engine will supplement the electric motor and provide the necessary power – running the engine in tandem with the electric motor means it won’t be under as much load, resulting in improved efficiency.

Examples of conventional hybrids include the well-known Toyota Prius and Lexus IS300h. While they all have slightly different ways of going about it, you’ll find conventional hybrid technology used by the likes of BMW, Land Rover, Lexus, Mercedes and Porsche.

Plug-in Hybrids

The newest hybrids to hit the market are known as plug-in hybrids. While the electric batteries in a conventional hybrid can only work on their own for a short range, plug-ins give you a much longer electric-only range. The extra distance is thanks to bigger batteries and more powerful electric motors. To make the most of the greater capacity, you’ll need to charge the car by plugging it in, just as you would with a fully electric car.

Manufacturers making use of plug-in hybrid tech include Mitsubishi, Volvo, Mercedes and Volkswagen. Read our list of the best plug-in hybrids to help you pick the one for you.

What are the pros and cons of hybrid technology?

The obvious advantage of choosing a hybrid is lower running costs – hybrids are among the most efficient vehicles on the road. You’ll find the the BMW i8 supercar is capable of over 100mpg in real world conditions, while the Mitsubishi Outlander PHEV can theoretically achieve 130mpg. It isn’t just fuel-efficiency either – hybrid owners won’t have to pay road tax thanks to their minuscule carbon footprint. Equally, thanks to the extended Government low emission grant, you’ll get a £5,000 discount if you choose to buy a plug-in today.

On the other hand, the high purchase price is a put-off – the seven-seater Toyota Prius+ will cost you more than £26,000 and, compared to similarly-sized rivals, it’s an expensive choice. Again, Mitsubishi’s Outlander PHEV costs around £7,000 more than a diesel Outlander – you’ll have to do a lot of miles to make up the greater purchase price in fuel savings. Hybrids tend to do best at lower speeds – if you regularly use the motorway in your commute, you’ll probably find a diesel will make a better choice.