Should you buy a diesel, petrol, electric or hybrid car? We’ll tell you all the facts so you can make the right choice for your needs, your lifestyle and your budget.

All power types explained

Long gone are the days where most cars had petrol engines and most vans and lorries used diesel. You just have to have a look at the market to see a wide range of power sources, from the good old petrol and diesel to eco-friendlier hybrid and electric. But more choices mean that making a decision can be harder for drivers.

To help you pick between the main engine types, here’s our complete guide to all fuels and their pros and cons.

Petrol cars

Despite an increase in the sales of hybrid and electric cars, as of 2021 petrol and diesel cars still dominate the car sales market in the UK. The two oldest power sources for vehicles have come a long way since their beginnings at the end of the 19th century.

Simply put, petrol is a liquid fuel made by distilling petroleum. We use it in traditional combustion engines, where the fuel is ignited with a spark and that powers the car. We produce petroleum from fossil fuels like crude oil, hydrocarbons, coal and natural gas.

Overall, petrol engines are less fuel-efficient than diesel ones but produce fewer particle emissions. It’s true that diesel cars produce 20% less CO2 than petrol but it’s also true that diesels emit more harmful particles of nitrous oxide, hydrocarbon and particulates. Overall, this makes petrol cars a little kinder to the environment – although not nearly as much as hybrid and electric cars.

Petrol cars are perfect for driving short distances in urban environments, although if you take them on the motorway they’ll still do great, but won’t be as efficient as a diesel.

Pros

  • A wider range of models
  • Cheaper to buy and repair
  • Fun to drive thanks to highly responsive engines
  • Improved petrol-efficiency

Cons

  • Price of fuel (though often cheaper than diesel)
  • They still produce CO2 (carbon dioxide) emissions, which are dangerous for the environment
  • Oil is a finite resource
  • Petrol vehicles depreciate faster than diesel ones

Diesel cars

Diesel cars are powered with diesel, a manufactured liquid fuel produced from mineral oil using a different process than petrol. In this case, diesel engines ignite the fuel by using air compression – and not a spark.

Traditionally this type of vehicle tends to be more fuel-efficient than their petrol counterparts. This makes them ideal for drivers who need to commute long distances or drive a lot of miles regularly. But, on the other hand, they produce more harmful emissions for the environment.

Pros

  • Depreciate less than petrol cars
  • Good for driving longer distances
  • Average 25% more fuel-efficiency than petrol cars
  • Lower road tax than petrol – due to lower CO2 emissions
  • Higher pulling power than petrol cars on average – makes them ideal for commercial vehicles

Cons

  • Historically more expensive to buy
  • Produces polluting particles like nitrous oxides, hydrocarbons and particulates – not greener than petrol engines
  • On average higher insurance costs
  • Tend to cost more to replace or repair
  • Fuel price volatility
  • Oil is a finite source of power
  • Engines tend to be noisier

Hybrid cars

Hybrid cars are vehicles that combine a battery pack and a petrol engine. They can use both together or separately, reducing emissions while keeping good mileage and speed. They still emit some particles, though, not like zero-emission electric cars.

Hybrid cars are a good choice if you are environmentally conscious but cannot commit to a fully electric car. That may be because there is no easy way for you to charge the batteries or you need to cover long distances regularly. In these circumstances hybrids are ideal.

There are three different types of hybrid vehicles that you can choose from:

  • Full hybrid – The most common type of hybrid vehicle. They use both a combustion engine and electric motors to power the car. They can do that simultaneously or independently from each other. For example, they can go fully electric for short distances at low speeds in an urban setting. Or switch to faster speeds and longer distances using the petrol engine. Their fuel economy is the best within hybrid cars.
  • Mild hybrid – They use a combustion engine and electric motor together, and never independently from each other. This is because the electric motor only assists the engine. For this reason, they are not as fuel-efficient as full hybrids, nor as eco-friendly. But they are the cheapest way to own a hybrid. Something you may want to consider.
  • Plug-in hybrid (PHEVs) – Plug-in hybrid cars are like an electric car. You can plug them in to recharge their electric batteries, which are bigger than in a full hybrid car. PHEVs deliver a much better electric-only range than other hybrids.

Pros

  • Cleaner and more fuel-efficient, particularly in urban environments
  • High resale values
  • Low congestion charges and tax bills
  • No range limits thanks to the conventional engine

Cons

  • Generally more expensive than petrol or diesel cars
  • Emit more emissions than a pure electric vehicle
  • Plug-in hybrids require charging infrastructure and take hours to recharge
  • Expensive to repair
  • Lower torque than diesel & petrol cars due to generally smaller engines

Electric cars

Electric cars – also called ‘electric vehicle’ (EV) – are cars that are powered only by a built-in battery and electric motor instead of the combustion engine that petrol and diesel vehicles use. The battery pack can be charged using a special cable, either at home, work or any of the 35,000 charge points in the UK.

If you want to reduce your carbon footprint electrics are the perfect option – these silent rides produce zero emissions and come in all shapes and sizes. Considering that the UK will ban sales of petrol and diesel cars by 2030 to cut pollution, switching to an electric car is a smart move.

The range and charge time of electric cars are improving all the time, but can still be an issue for those who need to cover very long distances in areas without enough charging points in the public network.

On top of being the most eco-friendly choice, EVs are cheaper to run than conventional cars. Whilst they are expensive to purchase, an off-peak recharge at home should cost you as little as £3/£4 for a full charge. And you can also wave goodbye to road tax and most congestion charging zones.

Electric cars are the new kids on the block and some people may feel a bit less confident about them. But there’s plenty of great reasons to give EVs a chance. Check out our electric cars section for more in-depth expert information.

Pros

  • Minimal running costs
  • Environmentally friendly – zero emissions
  • Minimal noise pollution
  • Zero road tax and congestion charging
  • Instant acceleration
  • Can charge overnight ready for the morning

Cons

  • High price tag
  • Limited range
  • Long time to recharge
  • Not fully developed charging network in some areas
  • Electricity is often generated by fossil fuel power stations

What to consider when deciding what car to buy?

Buying a car is a very personal thing since every driver will have different requirements. But overall, we’d recommend you pay attention to the following factors when picking your new ride:

1. Regular journeys

What’s the average distance you travel? Which are the journeys you make regularly? Do you mostly drive to work and back home? Do you need to drive long distances every day? Are you fond of lengthy road trips every weekend?

For example, if you don’t need to drive a lot every day and can have a charging point at home, then an electric car would be perfect for your daily commute, the school run or your errands.

Whereas if you need to cover long distances regularly, maybe a diesel or a hybrid would be better, particularly if you don’t want to be constrained by the range that electric cars have.

In any case, chances are there will be an ideal choice for your needs.

2. Emissions

Road transport accounts for 22% of total UK emissions of CO2, which contribute to global warming and air pollution. The average petrol car in the UK produces the equivalent of 180g of CO2 every kilometre. A diesel car produces 173g of CO2 per km.

Vehicles are necessary for many aspects of our daily life. That is why you should check how many emissions they generate before buying.

Whilst electric and hybrid vehicles would reduce significantly your carbon footprint, if these are outside your budget you could always opt for more environmentally-friendly petrol or diesel cars. All car manufacturers specify how much each of their models pollutes so that you can make an informed purchase.

3. Budget

Each type of car has a different price, and even within each category prices can vary widely. On average, hybrid and electric cars tend to have a higher price tag than traditional petrol and diesel vehicles. But once you own an electric or a hybrid the running costs are much lower.

Make some calculations and check if getting a cheaper petrol or diesel vehicle would cost you less in the long run. In some cases, you could make some savings by getting behind the wheel of a full hybrid or an EV.

4. Noise levels

Some drivers love the sound of a roaring petrol engine. Others will prefer the quietness that electric vehicles bring to the road. It’s a very personal choice and only you know what’s best.

5. Ability to charge

Only applicable if you’re thinking about making the switch to an electric vehicle or a hybrid, knowing where you can charge it is key. If you have a driveway, then you can install your charging point here, but you can also simply plug-in to your house mains. If not, some workplaces offer charging facilities. And on top of that, the UK has an ever-growing network of more than 35,000 public charging points for EVs – you can see them on Zap Map.

In the end, if you’re buying and driving an electric car you need to make sure you’ll be able to charge it so that it takes you where you want to.

FAQs about the different types of fuel

Should I buy a diesel car?

Diesel cars are more fuel-efficient than their petrol counterparts, especially on long journeys and out of urban areas. They also tend to have bigger towing power, just in case you have to carry heavy loads.

But other than that, diesel vehicles are usually pricier than petrol cars. And diesel fuel is more expensive than petrol in the UK. Plus, they tend to emit more polluting particles.

So, if you regularly drive long distances and need a more powerful engine, then a diesel car may be the best choice for your needs.

Where can I charge an electric car?

The UK has a public network of more than 35,000 charging points for electric cars and growing. You can charge your electric vehicle in any of them – the Zap Map is a really useful tool to find where they are – at home or work.

Why is diesel more expensive than petrol?

Traditionally diesel cars are more expensive than petrol cars because they need extra hardware that petrol ones don’t. For example, they need devices such as the AdBlue-reliant selective catalytic reduction (SCR) system fitted to reduce harmful emissions and to comply with EU laws.

The trade-off is that usually diesel cars offer better fuel-efficiency than their petrol counterparts. Even with the average cost of diesel fuel being slightly higher than petrol, the more economical engine makes up for this in the long run.

As you see, there is no straight answer to the petrol vs diesel vs. hybrid vs electric car debate. Whilst electrics are the way to go forward, all the other types of fuel have pros and cons worth considering when you’re looking for your next car.