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Have you ever stood at a petrol pump and wondered what all the different types of fuel are? Perhaps you’re interested in finding out what other fuel your car is able to take or are buying a new vehicle and unsure what it takes. You can find all about the various types in Australia, as well as how to determine what fuel your car takes, right here with Savvy today.
First of all, what do the numbers mean?
In Australia, the numbers you see next to petrol types at the pump indicate the Research Octane Number (RON). This number tells you the fuel's knock resistance, which is its ability to resist igniting prematurely inside your car's engine.
For example, unleaded 91 petrol represents the minimum RON available in Australia, with unleaded 98 being the maximum. This means that 98 has the greatest knock resistance and may be well suited to engines with high compression ratios.
How do I find out what fuel my car takes?
There are a few ways to find out what fuel your car takes in Australia:
- Look inside the fuel flap: many cars in Australia have a label on the inside of the fuel flap that indicates the recommended fuel type. This might be a simple text statement like “use unleaded petrol only” or simply “Unleaded 91”.
- Check your owner's manual: this is the most reliable and definitive source of information. Your car's owner's manual will clearly specify the recommended fuel type, including the required RON for petrol options.
- Check your car's model information online: you can search online using your car's make, model and year to find technical specifications that include the recommended fuel type. Reliable websites include manufacturer sites or reputable automotive information sites.
- Consult your mechanic: if you're unsure after trying the methods above, a qualified mechanic can help you determine the correct fuel type for your car. They can access technical information specific to your vehicle model.
What is unleaded 91 petrol?
Unleaded 91 petrol, also known as Standard Unleaded Petrol (ULP), is the most common type of fuel you'll find at service stations. It’s generally the cheapest pure petrol option available, making it a more budget-friendly choice for many Australians, and is suitable for most everyday vehicles on the road in Australia.
What is unleaded 95 petrol?
Unleaded 95 petrol, commonly known as Premium Unleaded Petrol (PULP), is a premium unleaded fuel option with a higher octane rating compared to the standard unleaded 91. As a result, it’s more expensive but can offer greater fuel efficiency. Certain high-performance and imported vehicles are designed to take premium 95.
Standard unleaded 91 vs premium 95 unleaded
| ULP (91) | PULP (95) | |
|---|---|---|
|
Price |
Cheaper |
More expensive |
|
Fuel efficiency |
Lesser |
Greater |
|
Often required in... |
Most standard passenger vehicles |
High-performance and imported vehicles |
|
Usable in opposite engine |
Not recommended |
Yes |
While standard 91 is cheaper and is designed for most passenger cars today, premium 95 can offer more fuel efficiency and may be a requirement if you’ve purchased one of the vehicles mentioned above. Additionally, while 91 isn’t recommended in a 95 engine, 95 can be used in a 91 engine, potentially offering improved fuel efficiency and a smoother performance.
What is unleaded 98 petrol?
In Australia, unleaded 98 petrol, also known as Ultra Premium Unleaded Petrol (UPULP), is the top-shelf option when it comes to unleaded petrol, boasting the highest octane rating readily available.
Unleaded 98 is ideal for cars with powerful engines, particularly those with features like turbochargers or superchargers. It can help optimise performance and prevent knocking. Similarly, cars that have undergone modifications for increased power might require or benefit from unleaded 98 to maintain optimal performance.
Unleaded 95 vs unleaded 98
| PULP (95) | UPULP (98) | |
|---|---|---|
|
Price |
Cheaper |
More expensive |
|
Fuel efficiency |
Lesser |
Greater |
|
Often required in... |
High-performance and imported vehicles |
Turbo-charged or modified engines |
|
Usable in opposite engine |
Not recommended |
Yes |
In the same way that 95 was an improvement on 91, 98 is an improvement on 95. However, if you’re deciding whether to use 98 or 95 in your car, it’s important to note that you may only see a marginal improvement in performance or fuel economy.
What is E10 petrol?
E10 is another type of unleaded petrol commonly available in Australia. It's a blend of regular unleaded petrol and ethanol, an alcohol typically derived from Aussie crops like wheat or sugarcane. The mix is typically 9% to 10% ethanol, with 10% being the cap implemented by the Australian Government. It can generally be used as an alternative to 91.
You may also come across E10 being marketed as 94 RON fuel, as the ethanol increases the RON by three when mixed with unleaded 91. Because of the way ethanol is created (in New South Wales, this is often done by fermenting leftover starch from the wheat to flour process), it’s considered a renewable biofuel.
Unleaded 91 vs E10
| ULP (91) | E10 | |
|---|---|---|
|
Price |
More expensive |
Cheaper |
|
Fuel efficiency |
Greater |
Lesser |
|
Often required in... |
Most standard passenger vehicles |
Most standard passenger vehicles |
|
Usable in opposite engine |
Not recommended |
Yes |
When tossing up between 91 and E10, it’s important to weigh up the cost against the fuel efficiency. Additionally, you may wish to consider the environmental impact; according to a CSIRO study in 2008, E10 reduces particle emissions by between 20% and 30% compared to standard unleaded petrol.
What is E85 petrol?
E85 is a type of fuel which uses a blend of 85% ethanol and 15% unleaded petrol. This is most commonly used by professional supercars, as well as those that have been modified to handle it, and comes with a RON of around 105.
Because of the high ethanol percentage, this fuel is capable of high performance, but its efficiency is lower than other types of petrol. However, according to NRMA, the availability of this type of fuel is limited in Australia for standard consumer vehicles.
What is diesel?
Diesel is a fuel source which is different from petrol. Although both are derived from crude oil, diesel has longer and heavier hydrocarbon chains compared to petrol, resulting in a difference in their chemical properties.
As well as being used in an increasing number of passenger cars, diesel is typically the fuel of choice for a wide range of commercial vehicles and equipment, from trucks and buses to farming equipment, trains, boats and more.
Petrol vs diesel
| Petrol | Diesel | |
|---|---|---|
|
Price |
Generally less expensive |
Generally more expensive |
|
Cars with matching engine |
Generally less expensive |
Generally more expensive |
|
Fuel efficiency |
Lesser |
Greater |
On the face of it, there are two clear areas of comparison between petrol and diesel cars: cost and efficiency. While diesel and diesel cars are generally more expensive, they can be up to 30% to 40% more fuel efficient, according to the RAC. However, working out which is better for the environment is a bit more complex.
A report by Paul Nieuwenhuis, Senior Lecturer and Co-Director of the Electric Vehicle Centre of Excellence (EVCE) at Cardiff University, for The Conversation outlines that while diesel engine CO2 emissions are lower than those of petrol engines, the nitrogen oxides (NO2) and particulate matter (PM) produced by the former can be extremely harmful to humans.
As a result, diesel engines typically use particulate filters, which can reduce PM emissions by up to 90% but can become clogged and require you to drive for longer periods to activate their self-cleaning systems.
What happens if I put the wrong type of fuel in my car?
The answer to this question depends on what the wrong fuel is. Consider the following scenarios:
91 in a 95 or 98 car
If you accidentally fill up your 95 or 98 car with 91 petrol, you’re unlikely to cause serious harm to your vehicle straight away. However, according to Shell, it will impact your car’s combustion cycle, which will result in a knocking sound in your engine. If you find yourself in this situation, Shell recommends using octane booster and/or fuel flusher.
Petrol in a diesel car or diesel in a petrol car
This mistake is a much more serious, and potentially costly, one. Driving with either petrol or diesel in your tank when your engine requires the other can cause significant damage, which can add up to thousands of dollars.
Avoid starting your car or pull over if you’re on the road when you realise. If you’re in a position to do so, call for roadside assistance to drain and refill your tank.
How to cut down on your fuel spend
- Drive smoothly: avoid harsh acceleration, sudden braking, and speeding. These habits can guzzle fuel. Aim for a smooth and steady driving style to maximise fuel efficiency.
- Maintain proper tyre pressure: underinflated tyres increase rolling resistance, which means your engine has to work harder and use more fuel. Check your tyre pressure regularly and inflate them to the recommended level (check your car's manual to confirm this).
- Reduce weight: the more weight your car carries, the more fuel it needs to move it. Avoid keeping unnecessary items in your car, such as removing roof racks or bike carriers when not in use.
- Use the right fuel: ensure you're putting the recommended fuel type in your car. To save on the cost, use the recommended type, rather than a higher, more expensive premium type.
- Consider E10 (if compatible): as mentioned, E10 can be a cheaper alternative to 91. However, ensure your car is compatible with E10 before using it (check your owner's manual).
- Shop around for fuel: petrol prices can vary between service stations. Use apps or websites to compare prices in your area and fill up at the most affordable station.
- Fuel rewards programs: some service stations offer rewards programs that give you discounts on fuel purchases or other benefits. Consider signing up for a program you frequent.
- Fuel efficiency features: if you're in the market for a new car, prioritise features that can improve fuel efficiency, such as start-stop technology or hybrid/electric options.
- Car maintenance: regular car maintenance, such as oil changes and air filter replacements, can help your engine run more efficiently and potentially save fuel in the long run.
If you're in the market for a new or used car, regardless of whether it takes 91, 95, 98, diesel or anything in between, you can compare a range of car finance options with Savvy today.
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