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Guide to Gas Oil

Learn more about gas oil by reading our short guide. We can also supply you with the gas oil you need today! Call our dedicated fuel team now on 0330 123 1444, for our very best price.

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Gas oil is a commercial fuel used as an alternative to road diesel. It has a lower tax duty and thus comes coloured red (leading to the name, red dye diesel) to help identify it’s usage by Customs & Excise (HMRC).

If a vehicle is suspected of using gas oil illegally, such as in vehicles used on public roads. The red dye will stain the fuel tank giving away its prior use within the vehicle.

You may hear people refer to the fuel as gas oil, but it is also known as red diesel as well due to the colour of the dye that’s added to gas oil. There may also be times when you hear it referred to as 35-second oil, tractor diesel and agricultural diesel which are some of the other more common names it often goes by. But gas oil and red diesel are the two most common names you’ll hear it being called.

Who can legally use Gas Oil?

There are regulations surrounding who can both buy and use gas oil in the UK. In general terms, it’s used by commercial customers and some households to heat up their businesses and homes. However, another more suitable option is to use heating oil for homes and industrial heating oil for businesses.

The other main uses are as a replacement for road diesel in non-road vehicles such as agricultural and construction vehicles. It is also used as the main source of fuel for diesel-powered machinery and equipment, such as generators.

Of course, there are many other uses as a replacement to regular white diesel, so long as you adhere to current regulations on its legal usage.

Which industries use Gas Oil?

There are a variety of different industries using gas oil such as; agriculture, horticulture and construction. It is used off-road, for machines and vehicles such as tractors and ride-on lawn mowers

For construction machinery, it is available to operators of excavators, dumper trucks, generators and pumps. It is also commonly used in diesel generators, manufacturing equipment, by councils and for some oil-fired heating systems. In more recent years, it has been used within data centres and hospitals, as fuel for backup generators.

What can Gas Oil be used for?

Gas oil cannot be used for road vehicles and does have rules which must be adhered to. You can take a look at our red diesel faq for a list of typical questions relating to rebated fuel or find a list of legal applications for red diesel fuel below.

  • Tractors, Diggers and Cranes
  • Backup Generators
  • Ride-On Mowers
  • Heating Fuel

The law was changed to allow agricultural vehicles to use red diesel when they’re gritting the roads. Other than this scenario, an agricultural vehicle can only travel a specified distance on public roads using rebated fuel, usually to go from one field to another when no other route is possible.

You can receive further advice from our advisors on 0330 123 1444 – call now for the latest gas oil prices, advice and availability.

Can you legally use Gas Oil in diesel-powered vehicles on the road?

As already stated, there are some restrictions and guidelines surrounding its usage, for instance, it is NOT a substitute for road diesel. Using it in a diesel-powered vehicle on a public road is an offence.

Although it is considerably cheaper than regular diesel due to the lower tax duty, the potential fines or prosecution incurred from using gas oil illegally could be much higher than any savings made.

Where does Gas Oil come from?

Gas oil is commonly created from petroleum. It is a fossil diesel which is derived from the fractional distillation of crude oil. When crude oil is added to a large chamber (fractionating column) and distilled in this way, the lower part of the chamber has a much hotter atmosphere which cools as it rises to the upper part. At various height levels in the column, temperatures vary from the bottom to the top whereby the atmosphere cools towards the upper part. There are several condensers fitted at different height levels which capture the vapours of different substances produced under the corresponding conditions.

Gas oil is one of the heavier substances which are created and it is collected near the lower level of the column, just above marine fuel oil and just below aviation fuel. Below marine fuel oil, a substance called bitumen is produced, which isn’t suitable as fuel and is commonly used for road surfaces instead.

The lower part of the fractionating column produces substances which have a higher boiling point and lower volatility, whereas towards the top of the chamber substances with a lower boiling point and higher volatility are produced.

We explain fractional distillation in greater depth in our dedicated guide on the subject – read it here.

Fractionating Column - How fuels and substances are made by fractional distillation - What is gas oil/how is it made? | Crown Oil

Click the image below to enlarge: Example of fractional distillation in the fractionating column.

What does Gas Oil cost?

The price of gas oil is much cheaper than regular road diesel which you pump into a diesel car because its purpose is for off-road use. The idea is to give relief to those using it for business rather than pleasure and recently, owners of pleasure craft; yachts and boats were refused the right to use gas-oil for propulsion. Although, gas oil can still be used onboard as fuel for light and heat.

With daily changes to gas oil prices, it’s difficult to put an actual price on rebated fuel, however, as a rebated fuel supplier, we check against competitors prices daily to ensure our gas oil prices are the most competitive in the UK.

Where can Gas Oil be purchased?

You can buy gas oil from registered gas oil suppliers such as ourselves! You don’t need a license to purchase rebated fuel, but you must adhere to the legal use of it or you could end up with a huge fine or even imprisonment. The supplier of your gas oil must be registered with HMRC.

As a nationwide gas oil supplier, Crown Oil can supply you with gas oil wherever you are in the UK at very competitive prices. Our priority focus is on customer care and timely deliveries although our oil is of the highest quality and our availability is second to none!

Ready to learn more about Gas Oil and request a quote?

Hopefully, we’ve been able to answer many of your questions about gas oil. But should you want to find out more, we have further information on our frequently asked gas oil (red diesel) questions and answers page. You can also view the full range of fuel and oil products we can supply if you have further requirements.

If you have any further questions or would like to discuss your own requirements, our gas oil experts will be able to assist you by calling us today on 0330 123 1444. You can also request a quote and purchase gas oil by calling the same number.

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