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Which fuel?

Choosing the right fuel type is essential when buying a car. So which one should you go for?

We look at the pros and cons of every fuel available today.

 

Petrol | Diesel | LPG | Biofuel | Electricity |
Hybrids | Solar power | Hydrogen

 

Petrol

Still the best choice for performance when driving, petrol is the most popular fuel with motorists across the UK. 

Pros:
• Responsive
• Quieter than diesel
• Petrol engines are generally cheap to repair
• Faster revving

Cons:
• Petrol engines are less environmentally-friendly than their diesel counterparts
• It’s non-renewable
• Produces more CO2 than other fuel types

Each type of petrol has its own research octane rating (RON). The higher the number, the better performing the petrol is. It essentially falls into four main categories:

1. Unleaded
The most common type of petrol, this has a RON of 95.

2. Super Unleaded
Much like unleaded, but with 98 RON it gives your vehicle better performance.

3. Leaded Four Star and Lead Replacement Petrol (LRP)
Leaded fuel was removed from sale back in 2000 and replaced by LRP. This fuel is basically 97 RON unleaded petrol with an additive to give the valve seat protection, which some cars need.

A valve seat is a surface inside a car’s engine, which rests against the air intake or exhaust valve when the valve is closed – so to stop it from moving out of place and possibly reducing the engine’s efficiency.

LRP is generally only used for vintage vehicles so is less common.

4. High Performance
Cleaner and more powerful than super unleaded, high performance fuels are also more expensive. BP Ultimate is currently the most advanced fuel in UK petrol stations, with 102 RON.

High octane racing fuels are available in specialist motor stores, with prices going up to £7 per litre for 110 RON types.

But the difference between super unleaded and high performance fuels is marginal and more obviously noticed in supercars and other high performance vehicles.

Summary:
Best for driver’s who enjoy optimal performance and a smooth ride.

Diesel

Diesel is becoming more popular, due to its efficiency benefits over petrol and its lower CO2 emissions.

Pros:
• Stays in each gear longer, helping with acceleration and reducing the need for gear changing
• High engine efficiency
• Lower CO2 emissions
• Some high performance fuels are available in diesel

Cons:
• Diesel engines are louder than their petrol counterparts
• Results in a less smooth ride
• More expensive than petrol by a couple of pence
• Higher Nitrogen Oxide (an air pollutant) emissions than petrol

Summary:
More environmentally friendly and economical for long distance drivers.

Liquid Petroleum Gas (LPG)

Commonly known as autogas, LPG is cheaper than petrol and converting a car to run on it is reasonably painless.

It’s possible to get your engine converted to run on LPG. To find out more about conversions, and which petrol stations provide LPG, visit our LPG Cars advice page.

Pros:
• Less emissions than petrol and diesel
• Half as noisy as diesel
• Cheap

Cons:
• You need to convert your engine
• Not all cars can be converted to run on LPG
• LPG isn’t available at every garage

Summary:
Good for long term savings on fuel and it's environmentally-friendly.

Biofuels

Fast becoming an alternative to petrol and diesel, biofuel uses renewable energy sources to power vehicles. Some of these vehicles have flexi-fuel engines, which allow both bioethanol and petrol in the tank.

There are two types of biofuel:

Bioethanol

Produced from everyday farm crops, bioethanol is an environmentally-friendly fuel type with a high octane rating for better performance.

Pros:
• Lower CO2 emissions
• High RON
• Low fuel consumption

Cons:
• Not as widely available as leaded
• Difficult to find

Biodiesel

Made from animal fats, sugar beet and vegetable oils, biodiesel fuel is less toxic than normal diesel and is swiftly growing in popularity with greener diesel drivers.

Pros:
• Lower CO2 emissions
• Lower engine wear
• Can be used in most normal diesel vehicles
• Can be gathered from restaurants and chip shops

Cons:
• May require engine modifications
• Not as readily available as normal diesel

Summary:
Good for long distance drivers who like both high performance and being environmentally friendly.

Use this Energy Saving Trust page to locate biofuel refuelling stations in the UK.

Electricity

These vehicles can be recharged at a charging station, in garages or at home. Charge time varies from make to model.

Pros:
• No emissions from the vehicle
• No car tax
• Exempt from London congestion charge*
• Very quiet
• Good acceleration

Cons:
• Requires a lot of electricity
• Indirect emissions from power station when charged
• Many have a short range (approximately 50 miles)
• Most have a lower top speed of around 40-50mph

Summary:
Perfect for the inner city driver who makes short journeys at low speeds.

Hybrids

Hybrid vehicles combine a rechargeable electric system with a fuel-based engine. Usually the car battery is recharged by the internal combustion engine or from kinetic energy absorbed when braking. This results in impressive fuel economy and better efficiency.

Pros:
• Lower fuel consumption
• Lower CO2 and other pollutant emissions
• Quick acceleration
• Quiet drive

Cons:
• Expensive
• Not as readily available as petrol and diesel cars

Summary:
Great for those who use both the city and the motorway - without the need for high performance.

Hydrogen

Hydrogen vehicles convert the chemical energy of Hydrogen into mechanical energy to give the car power.

Pros:
• No CO2 or other emissions
• Environmentally-friendly

Cons:
• Hydrogen is highly flammable
• Hydrogen fuel cells are fragile
• Hard to obtain and store

Summary:
A good choice for the eco-conscious driver who thinks about the future and has some extra money to spend on it.

Solar power

These types of cars are a less common sight on the roads, due to high production costs.

Pros:
• No CO2 or other emissions
• Great renewable energy source makes them cheap to run
• Very quiet

Cons:
• Cloudy and rainy weather will affect their speed
• Not ideal for night time driving
• Good idea, but difficult to implement and obtain

Summary:
For anyone who lives in a bright sunny location and likes their cars covered in solar panels.

 

*Talks regarding the congestion charge price changes on October 27 are still ongoing between the Mayor and Transport For London. To register your car for exemption, call TFL on 0845 900 1234 or visit Transport for London’s registry page.

 

 

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