The terms biofuel and biodiesel are often used as though they mean the same thing. They do not.

For businesses, farmers, transport operators and other fuel users in the UK, understanding the difference matters because choosing the wrong fuel can affect engine compatibility, storage, fuel performance, emissions, operating costs and regulatory requirements.

The simplest way to think about it is this:

Biofuel is the broad category. Biodiesel is one type of biofuel.

But that simple definition only tells part of the story. Biofuels include several different fuels made from renewable biological materials, while biodiesel specifically refers to diesel-type fuel produced from biological oils or fats and processed for use in suitable diesel engines.

There is also another fuel that increasingly causes confusion: HVO (Hydrotreated Vegetable Oil). HVO is a renewable diesel fuel, but it is chemically different from conventional biodiesel.

For UK fuel buyers, knowing these distinctions can make a significant difference when deciding which fuel is appropriate for a vehicle, generator, agricultural machine, heating application or commercial operation.

What Is Biofuel?

Biofuel is a general term used for fuels produced from renewable biological materials rather than exclusively from fossil resources.

These biological materials, often called biomass, can include:

• Vegetable oils
• Used cooking oil
• Animal fats
• Agricultural crops and residues
• Forestry materials
• Organic waste
• Other renewable biological feedstocks

Biofuels can be produced in different forms depending on the feedstock and manufacturing process.

Some biofuels are designed for diesel engines, while others are used in petrol engines, heating applications, industrial processes or energy generation.

This is why referring to every biofuel simply as "biodiesel" can create confusion.

Common Types of Biofuel

The biofuel category can include:

• Biodiesel
• HVO
• Bioethanol
• Biogas
• Biomethane
• Other advanced and emerging renewable fuels

Each fuel has different chemical properties, production methods and applications.

For example, bioethanol is commonly associated with petrol fuel blends, whereas biodiesel is designed around diesel applications.

What Is Biodiesel?

Biodiesel is a specific type of biofuel intended primarily for diesel engines.

Unlike conventional diesel, which is produced from crude oil, biodiesel is manufactured from renewable biological oils and fats.

Common feedstocks can include:

• Rapeseed oil
• Soybean oil
• Used cooking oil
• Animal fats
• Other vegetable oils and waste-derived oils

The oils or fats are processed through a chemical conversion process known as transesterification. This produces fatty acid alkyl esters, commonly referred to as FAME (Fatty Acid Methyl Esters).

This is an important distinction because biodiesel is not simply vegetable oil poured into a diesel tank.

Is Biodiesel the Same as Vegetable Oil?

No.

Straight vegetable oil and biodiesel are not interchangeable terms.

Vegetable oil has different physical and chemical characteristics from properly manufactured biodiesel. Using untreated vegetable oil in an engine that has not been designed or modified for it can create operational problems.

Biodiesel, on the other hand, is processed to meet fuel specifications and can be used in compatible diesel applications.

Biofuel vs Biodiesel: The Main Difference

The easiest way to understand the relationship is to consider biofuel as the umbrella term.

Biodiesel sits underneath that umbrella.

So asking whether biofuel is better than biodiesel is slightly misleading.

A more useful question is:

Which type of biofuel is suitable for your particular application?

Is Biodiesel a Biofuel?

Yes.

Biodiesel is a biofuel.

The relationship is similar to saying that a particular car is a vehicle. "Vehicle" is the broader category, while the specific car is one example within it.

The same principle applies here:

Biofuel → broad category

Biodiesel → one specific type of biofuel

HVO → another renewable diesel fuel

That distinction becomes especially important when comparing biodiesel with HVO.

Biodiesel vs HVO: Why Are They Often Confused?

Biodiesel and HVO are both renewable alternatives to fossil diesel, but they are produced differently and have different chemical characteristics.

Biodiesel is generally made through esterification or transesterification and produces FAME.

HVO is produced through a hydrogenation process that removes oxygen from the original oils or fats, resulting in a hydrocarbon fuel that is much more chemically similar to conventional diesel.

This difference can influence:

• Fuel storage
• Cold-weather performance
• Fuel stability
• Engine compatibility
• Blending requirements
• Long-term fuel management

HVO should therefore not simply be described as "another name for biodiesel".

It is a different renewable diesel fuel.

What Is HVO Fuel?

HVO stands for Hydrotreated Vegetable Oil.

Despite the name, modern HVO production is not limited to fresh vegetable oil. Depending on the producer and fuel supply, renewable waste and residue feedstocks can also be used.

HVO is often described as a renewable diesel because its chemical structure is much closer to conventional diesel than FAME biodiesel.

This makes HVO increasingly interesting to UK businesses looking to reduce the fossil component of their fuel use without immediately replacing diesel-powered equipment.

However, suitability should always be checked against the equipment manufacturer's requirements and the relevant fuel specification.

Biodiesel and HVO: Which One Is Better?

There is no universal answer.

The better option depends on the equipment, fuel specification, availability, storage arrangements, operating conditions and environmental objectives.

Biodiesel May Be Appropriate When:

• Equipment is approved for the relevant biodiesel blend
• A FAME-based fuel is suitable for the application
• The fuel meets the required specification
• The operator has appropriate fuel storage and management procedures
• The business wants to incorporate renewable content into its diesel supply

HVO May Be Attractive When:

• Equipment is approved for HVO
• A renewable diesel replacement is being considered
• Long-term fuel storage is important
• Cold-weather operation is a consideration
• The operator wants a fuel with properties closer to conventional diesel

Neither fuel should automatically be considered suitable simply because it is marketed as "green" or "renewable".

Fuel compatibility comes first.

Why Are UK Businesses Looking at Biofuels?

The UK's transition towards lower-carbon energy is encouraging businesses to examine alternatives to conventional fossil fuels.

This is particularly relevant for sectors where replacing diesel equipment entirely is difficult.

Agriculture, construction, logistics, backup power and industrial operations can involve machinery that needs dependable liquid fuel.

For these users, changing the fuel can sometimes be more practical than replacing an entire fleet or equipment base.

Biofuels can therefore form part of a wider strategy involving:

• Fuel efficiency
• Renewable energy
• Lower-carbon operations
• Equipment modernisation
• Alternative fuels
• Better fuel management

The right approach depends on the individual operation rather than a one-size-fits-all solution.

Can UK Farms Use Biodiesel?

In suitable equipment, biodiesel can be an option for agricultural operations.

However, farmers should not assume that every tractor, telehandler, generator or other diesel-powered machine is automatically compatible with every biodiesel product or blend.

Before changing fuel, check:

1. The equipment manufacturer's guidance.
2. The required fuel specification.
3. Whether the engine permits the proposed biodiesel blend.
4. Storage requirements.
5. Warranty conditions.
6. Any applicable UK fuel regulations and tax requirements.

This is particularly important for farms because fuel may remain in storage for extended periods and equipment may be used intermittently.

A fuel that works well in one application is not necessarily the right choice for another.

Can Biodiesel Be Stored?

Yes, but fuel storage management matters.

Biodiesel can behave differently from conventional mineral diesel during storage. Factors such as temperature, exposure to air, water contamination, tank cleanliness and storage duration can influence fuel quality.

Good fuel management should include:

• Keeping tanks clean
• Preventing water ingress
• Inspecting storage tanks regularly
• Using appropriate filters
• Monitoring fuel condition
• Avoiding unnecessary long-term storage
• Following supplier and equipment recommendations

For businesses that rely on stored fuel, purchasing the right quantity at the right time can be just as important as selecting the fuel itself.

Does Biodiesel Work in Diesel Engines?

It can, but engine compatibility is essential.

Some diesel engines are approved for particular biodiesel blends, while others may have restrictions.

Older equipment can be particularly important to check because seals, hoses and fuel-system components may not have been designed with modern biodiesel blends in mind.

Do not assume that because a vehicle has a diesel engine it can automatically run on any biodiesel product.

Always follow the manufacturer's instructions and the fuel specification applicable to the equipment.

Is Biofuel Better for the Environment?

Biofuels can offer environmental advantages compared with fossil fuels, but the answer depends heavily on how the fuel is produced and what feedstocks are used.

It is too simplistic to say that every biofuel is automatically sustainable.

The overall environmental impact can depend on:

• Feedstock source
• Land use
• Agricultural practices
• Production methods
• Processing energy
• Transportation
• Waste and residue utilisation
• Fuel efficiency
• End-use application

Waste-derived and residue-based feedstocks can have a very different sustainability profile from purpose-grown crops.

For this reason, responsible fuel purchasing should consider the whole fuel supply chain, not just the label on the tank.

Are Biofuels Renewable?

Many biofuels are considered renewable because their feedstocks originate from biological resources that can be replenished.

However, "renewable" does not mean that every biofuel has the same environmental impact.

A renewable fuel can still involve significant energy use, transportation or agricultural inputs during production.

The quality of the feedstock and production pathway matters.

This is why modern discussions around renewable fuels increasingly focus on sustainability, waste feedstocks, lifecycle emissions and responsible sourcing, rather than simply whether a fuel is technically renewable.

Biofuel, Biodiesel and Fossil Diesel: What's the Difference?

For a straightforward comparison, consider the three categories separately.

Fossil Diesel

Traditional diesel is produced from crude oil.

It remains widely used across UK transport, agriculture, construction and industrial applications.

Biodiesel

Biodiesel is a renewable diesel-type fuel generally produced from oils and fats and converted into FAME.

It can be used in compatible diesel applications, subject to the relevant fuel specification and manufacturer's approval.

Other Renewable Diesel Fuels

HVO is an important example.

It is manufactured differently from FAME biodiesel and has properties that make it a potential alternative to conventional diesel in approved applications.

Understanding this distinction prevents businesses from treating all renewable fuels as interchangeable.

What Should UK Fuel Buyers Consider Before Switching to Biofuel?

Changing fuel should be treated as a fuel-management decision, not simply an environmental decision.

Before ordering a new fuel, consider:

1. Equipment Compatibility

Check the manufacturer's fuel requirements.

This should be the first step.

2. Fuel Specification

Do not purchase solely on the basis of a product name.

Ask which specification the fuel meets.

3. Storage Conditions

Consider tank cleanliness, water contamination, storage duration and fuel turnover.

4. Operating Environment

Agricultural and industrial equipment may operate in demanding conditions, including cold weather and irregular duty cycles.

5. Fuel Availability

A fuel strategy is only useful if you can obtain a consistent supply when required.

6. Total Operating Cost

Look beyond the price per litre.

Consider delivery, storage, fuel efficiency, maintenance requirements and operational reliability.

7. Environmental Objectives

If reducing carbon emissions is part of the reason for switching, investigate the fuel's feedstock and sustainability credentials rather than relying solely on the word "biofuel".

Is Biodiesel Cheaper Than Diesel?

There is no permanent price advantage that applies in every situation.

Fuel prices vary according to market conditions, feedstock costs, production costs, taxation, supply and demand, delivery requirements and other factors.

For commercial users, comparing only the pump or delivered price may therefore give an incomplete picture.

A more useful comparison considers the total cost of using the fuel.

For example, storage requirements, fuel consumption, equipment compatibility and supply reliability can all influence the real operating cost.

Should You Choose Biofuel or Biodiesel?

In most cases, this is not really an either-or decision.

Biodiesel is already a type of biofuel.

The more useful decision is to identify the specific renewable fuel that matches your equipment and operational requirements.

For a UK farm, that could mean investigating biodiesel blends or HVO.

For a commercial fleet, the decision could depend on vehicle approvals and fuel availability.

For a generator operator, storage life and equipment compatibility may be more important than the headline fuel price.

For an industrial user, dependable bulk supply may be a major consideration.

The best fuel choice is therefore the one that balances compatibility, performance, availability, cost, storage and environmental objectives.

The Future of Biofuels and Biodiesel in the UK

The UK's fuel landscape is becoming more diverse.

Businesses are increasingly considering alternatives to traditional fossil fuels while still relying on equipment that requires liquid fuel.

That creates an important role for renewable diesel options.

Biodiesel, HVO and other renewable fuels are likely to remain part of the wider transition, particularly in sectors where electrification is challenging or where existing diesel equipment has years of useful life remaining.

However, the future is unlikely to involve one single replacement fuel.

Instead, businesses may use a combination of technologies and fuels depending on the application.

For some operations, electrification may make sense.

For others, HVO or biodiesel may provide a more practical transition.

The key is to make the decision based on the actual operating environment rather than choosing a fuel simply because it sounds more sustainable.

Final Verdict: Biofuel vs Biodiesel

So, what is the difference between biofuel and biodiesel?

The answer is straightforward:

Biofuel is the broader category, while biodiesel is a specific type of biofuel designed for diesel applications.

HVO is another important renewable diesel fuel, but it should not be confused with FAME biodiesel because the two fuels are manufactured differently and have different chemical properties.

For UK farmers, fleet operators, businesses and industrial fuel users, the most important question is not simply "Which fuel is greener?"

It is:

Which renewable fuel is compatible with my equipment, suitable for my operating conditions, available from a reliable supplier and appropriate for my long-term fuel strategy?

Once those questions have been answered, comparing biodiesel, HVO and conventional diesel becomes much more meaningful.

Frequently Asked Questions About Biofuel and Biodiesel

Is biofuel the same as biodiesel?

No. Biofuel is a broad term covering fuels made from biological renewable materials. Biodiesel is one specific type of biofuel designed primarily for diesel applications.

Is biodiesel a renewable fuel?

Yes. Biodiesel is generally produced from renewable biological feedstocks such as vegetable oils, used cooking oils and animal fats. Its overall sustainability depends on the feedstock and production pathway.

Is HVO a biodiesel?

No. HVO and biodiesel are different fuels. Biodiesel is generally a FAME fuel, whereas HVO is a hydrocarbon renewable diesel produced through hydrotreatment.

Can biodiesel replace diesel?

It can in suitable applications, but compatibility depends on the engine, vehicle, equipment and fuel blend. Always check the manufacturer's requirements before switching.

Can farmers use biodiesel in agricultural machinery?

Potentially, yes. Many agricultural machines use diesel fuels, but farmers should check individual equipment specifications, approved fuel blends and manufacturer recommendations before using biodiesel.

Is biodiesel better than HVO?

Neither is automatically better for every application. Biodiesel and HVO have different production methods and fuel characteristics. The right choice depends on equipment compatibility, storage, operating conditions, supply and environmental objectives.

Is HVO better than biodiesel for storage?

HVO is often considered advantageous for applications where fuel stability and longer-term storage are important, but storage conditions still matter. The exact requirements should be confirmed with the fuel supplier and equipment manufacturer.

Does biodiesel reduce carbon emissions?

Biodiesel can reduce lifecycle greenhouse-gas emissions compared with fossil diesel, but the reduction varies considerably depending on the feedstock, production process and supply chain.

Can you mix biodiesel with diesel?

Certain biodiesel blends are specifically designed to be mixed with conventional diesel, but the permitted blend and equipment compatibility depend on the fuel specification and manufacturer requirements.

Is vegetable oil the same as biodiesel?

No. Vegetable oil is a raw feedstock that can be used to manufacture biodiesel. Untreated vegetable oil should not automatically be used as a substitute for diesel fuel.

What is the main advantage of biofuel?

One major advantage is that biofuels can provide renewable alternatives to fossil fuels. Depending on the fuel and feedstock, they can help reduce lifecycle greenhouse-gas emissions compared with conventional fossil fuels.

What is the main disadvantage of biodiesel?

Biodiesel has different fuel properties from conventional diesel, which can affect compatibility, storage and performance in certain applications. Proper fuel selection and storage management are therefore important.

Is biodiesel suitable for generators?

It can be suitable for compatible generators, but the generator manufacturer's fuel requirements should always be checked first. This is particularly important for standby generators where fuel may remain stored for extended periods.

Should I choose biodiesel or HVO for my business?

Start with the equipment manufacturer's approved fuels, then compare the relevant fuel specifications, availability, storage requirements, operating conditions, delivered cost and sustainability credentials. A reputable commercial fuel supplier can also help you assess the practical differences between available options.

What is the simplest way to remember the difference?

Think of it this way:

Biofuel = the wider family.

Biodiesel = one member of that family.

HVO = another renewable diesel option, but not the same as biodiesel.

That simple distinction can prevent a surprising amount of confusion when comparing renewable fuels in the UK.