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Nationwide Fuels

Guide to Gas Oil

Learn more about gas oil, the low fuel duty alternative to white diesel. Read our FAQ for a detailed insight into its usage.

Learn More About Gas Oil, the Cheaper Alternative to Diesel

Whether you’re new to gas oil, or just want to learn more about how this fuel can be used, Nationwide Fuels have put together this short guide to provide you with a better understanding.

We’re a national gas oil supplier and can not only supply any quantity from 500 litres through to 36,000 (or more), as well as 205-litre barrels if required. Speak to our knowledgeable gas oil experts today and call 0330 678 0880 for your competitive red diesel quote.

What is gas oil?

Gas oil, also known as red diesel, is a low fuel duty variant of regular road diesel. It’s blended with a red dye marker to help signify illegal use; other than the colour, gas oil is exactly the same fuel as the road diesel you find at any UK petrol station.

Many industries and sectors currently make use of gas oil including agriculture, forestry and rail transport. Hospitals and some other non-commercial facilities can also use gas oil in backup generators too.

Which industries use gas oil in the UK?

The most well-known and widespread users of gas oil are within the farming industry, who make major use of the rebated fuel in their farm vehicles such as tractors, utility vehicles and combine harvesters.  This is why gas oil is often referred to as agricultural diesel.

Gas oil is also often used in grain dryers, but this isn’t the best or cheapest fuel available for the job. Industrial heating oil (IHO) is a far better option this purpose as it has been specifically designed for use in heating applications. You can find out more about IHO in our dedicated heating oil FAQs.

Beyond farming and agriculture, gas oil is also used by a number of commercial and industrial sector businesses to power machinery and other equipment, as well as in emergency generators for hospitals and non-commercial buildings.

At Budget 2021, the Chancellor announced that many sectors, including construction, will lose their entitlement to use gas oil from 1 April 2022. This change in legislation will pose a challenge for many businesses, mainly the high-cost implications that will follow as a result of switching to a higher duty fuel.

Read more about the 2021 budget here.

Which vehicles can run on gas oil?

There is a commonly-held belief that gas oil is a unique type of fuel, as it’s mostly known as a fuel for agricultural and horticultural vehicles.

However, gas oil is simply standard diesel that’s been blended with a red dye marker. This means that any engine that is designed to use diesel will technically be able to use gas oil – so long as the machine or engine has legal clearance to do so i.e. it does not travel on the road, and is being used by an eligible industry.

Is gas oil exempt from tax?

Gas oil is not completely exempt from tax, but it is taxed at a lower rate (11.14p per litre) than the white diesel you’ll find at petrol filling stations (57.95p per litre).

Compared to white diesel, gas oil has a considerably lower tax applied to it. If you need to receive a tax rebate for using gas oil, you will need to fill in an HO27 form and send it to HMRC.

Is it illegal to use gas oil on public roads?

It is illegal to use gas oil on public roads. At the time of writing, farmers have a specific exception and are able to use public roads to access to another piece of land within 1.5km, so long as both are owned by the same individual or business.

Vehicles used for gritting roads during cold weather are also allowed to use gas oil, strictly for this purpose only. You can find information on the HMRC website to make sure you’re using gas oil legally.

What happens if I use gas oil illegally?

Fuel fraud is a serious crime, and the number of prosecutions has risen in recent years.

If HMRC successfully prosecutes you for fuel fraud, you will be fined, given a criminal record and may even receive a custodial sentence. In most cases, you will also have to pay a fee for the following:

  • Returning your vehicle’s system to its previous state
  • Cleaning of the tank so all trace of the red dye is cleared away
  • The safe removal of the gas oil from your engine
  • Occasionally, they will charge you the price difference between gas oil and regular white diesel (DERV)

I do not use my car on public roads, can I use gas oil?

So long as your vehicle is solely used for the purpose of being driven on private land, you may be able to use gas oil in your vehicle.

It would also be advisable to register your vehicle as off-the-road with a SORN (Statutory Off-Road Notification). This should help ensure HMRC and other authorities are clear that the car is only for off-road usage.

However, if you intend to use your vehicle on the road in the future, it’s important to note that gas oil’s red dye stains the interior of your tank, fuel lines and engine. Therefore it must be cleaned, so no traces of the dye or chemical markers remain before you are able to drive on the roads.

If you are found to be driving on the road with traces of gas oil’s dye in your engine, you could be vulnerable to prosecution.

What can I do if I put gas oil in my car by accident?

First of all, you should ensure that your vehicle is capable of running on diesel fuel. If your vehicle is a petrol engine vehicle, then the same advice regarding using diesel in a petrol engine vehicle can be used. You can learn more about what to do by reading advice from the RAC and advice from the AA.

If you’ve put gas oil into your diesel vehicle then you should contact HMRC immediately. They will advise you on the next steps to take.

What if I have gas oil I no longer need?

There are many reasons why you no longer need gas oil, including:

  • Your sector has lost its eligibility
  • You’re switching to a renewable fuel such as HVO fuel
  • You’re moving premises

Storing fuels for excessive periods of time can often lead to them becoming contaminated, which can also affect any new gas oil that is added to existing stock. It will also likely cause issues for any vehicles or machinery which are powered by contaminated fuels.

As a fuel user, you are responsible for the safe and legal disposal of your fuel. Here at Nationwide Fuels, we provide a professional fuel uplift and transfer service to help with the issue of removing fuel you no longer need.

If you’d like to discuss the removal or transfer of your old or surplus gas oil or any other fuels, call our team on 0330 678 0880 today. They will be able to discuss your requirements and create a tailored action plan to ensure that your fuel is disposed of safely.

Is gas oil known by any other names?

As we’ve already mentioned, gas oil is commonly referred to as red diesel because of the presence of a red marker dye. However, gas oil is also known by several other names which can often add to the confusion for those new to using this type of fuel. Some of the names you may have come across may include:

  • Red diesel
  • Cherry diesel/cherry juice
  • Agricultural diesel
  • Tractor diesel
  • Marine diesel
  • Generator diesel

Why is it called red diesel? Is it actually red?

The low fuel duty diesel known as gas oil has been around for many years, but it wasn’t until the mid-20th century that it became a requirement to add red dye and chemical markers to the fuel to distinguish it from regular road diesel

The name red diesel became popular owing to the fact that red dye marker gave the fuel a distinctive red appearance, with regular road diesel often being referred to as white diesel as a consequence.

What will happen to the price of gas oil in 2022?

Government plans announced in the Budget 2020 mean that access to gas oil will be restricted from April 2022.

A number of sectors and industries will lose the legal right to use gas oil. They will instead have to use non-rebated white diesel or switch to renewable alternatives, such as HVO fuel.

We’ve created a short guide to the changes for red diesel users who are concerned they may lose their eligibility.

Call our team today on 0330 678 0880 for the latest gas oil prices.

Gas oil specification sheets

If you would like to know more about gas oil, take a look at our specification sheets below.

Where can I buy gas oil from the in the UK?

We can supply gas oil across the UK 365 days a year. We also have a 24-hour emergency fuel delivery service, ensuring that you can avoid the costs of forced downtime.

If you’d like to learn more or get a quote, call our fuel experts on 0330 678 0880 to place your order today.

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