Types of biofuels
Biofuels usually come in the form of biodiesel (as an alternative to diesel) and bioethanol (as an alternative to petrol). Biofuels are normally used as a blend with ordinary diesel or petrol.
On this page:
Biodiesel: what it is, and how to use biodiesel blends
Bioethanol: What it is, and how to use bioethanol blends
Biodiesel
What is biodiesel?
Biodiesel is similar to ordinary diesel but is made from vegetable oils or animal fats. Blended with ordinary mineral diesel, it makes a biodiesel blend.
Biodiesel has been in use overseas for nearly 20 years. Countries that currently produce and use biodiesel include most of the European countries, the United States, Canada, Brazil and Australia.
In New Zealand biodiesel will be available for retail sale as a blend comprising up to 5% biodiesel and 95% ordinary diesel. A 5% blend is the maximum allowed for retail sale.
Using biodiesel
Most people who use diesel will be able to use biodiesel blends without noticing any difference.
- Biodiesel and ordinary diesel are fully compatible, so it doesn't matter if you swap between them each time you fill up
- Engine modification is not needed
- Engine performance is not compromised.
Fuel quality
You can be confident about the quality of bidiesel blends available for retail sale in New Zealand, as they must meet government-regulated fuel specifications.
Vehicle compatibility
Most people who use diesel engines will be able to use biodiesel blends without noticing any difference, and without any engine or fuel system modifications. You can fill up with a biodiesel blend or ordinary diesel, and have a mix of both in your tank at the same time.
Helps engine performance
Biodiesel has good combustion and lubrication properties, making it a good option for your engine.
Useful tips
When first using a biodiesel blend, follow these simple tips. To make it as easy as possible, you can get these done when your vehicle is next serviced.
Check your fuel system
If your fuel system is old or in poor condition, it may be worth flushing it out before using biodiesel blends. A mechanic can easily do this for you.
Change your fuel filter
Because biodiesel blends have stronger cleaning properties than diesel, they can loosen dirt and carry it through to the fuel filter. If your fuel filter hasn't been changed recently, it should be changed after the first few fills of biodiesel blends.
Summer and winter conditions
In winter, avoid parking in the mountains or overnight in very cold areas if the biodiesel blend has not been purchased locally. Simply driving through these areas is not a problem. There are summer and winter versions of both normal diesel and biodiesel blends. These are used at different times in regions of New Zealand, according to the weather.
Storage and handling
Biodiesel blends should be cared for in the same way as ordinary diesel. They should be stored in closed containers in dry, cool and dark spaces.
They should be stored for no longer than three months, otherwise they may absorb moisture from the air. If you have any doubts, check the vehicle or equipment handbook or with the supplier.
Avoid ‘backyard biodiesel'
It is illegal to sell biodiesel or bioethanol that does not meet the Engine Fuel Quality Regulations.
EECA recommends only purchasing biodiesel from established fuel retailers, once it is commercially available - i.e. the same places you would normally purchase petrol or diesel from.
‘Backyard' biodiesel may not meet quality specifications and may result in engine damage, so is not recommended.
More information on specifications and regulations concerning biofuels.
What is bioethanol?
Bioethanol is a biofuel that is made from wastes, by-products and plants that contain sugars and starches. Bioethanol is usually available as a blend, mixed with petrol.
In New Zealand bioethanol-blended petrol is available in blends of up to 10%. A 10% blend means 10% bioethanol in ordinary petrol. Likewise, a 3% blend means 3% bioethanol in ordinary petrol.
Bioethanol blends are often referred to as E3, E5, or E10. These names relate to the percentage of bioethanol in the petrol mix.
You can switch between using bioethanol-blended petrol and ordinary petrol in your vehicle at any time.
Using bioethanol-blended petrol
Fuel quality
You can be confident about the quality of bioethanol-blended petrol for retail sale in New Zealand, as it must meet government-regulated fuel specifications.
Vehicle compatibility
Most new and many older vehicles can use bioethanol-blended petrol.
The Automobile Association (AA) website has a list of vehicles that support the use of bioethanol-blended.petrol.
To find out if your vehicle supports the use of a bioethanol blend visit the AA website. You can also contact the official representative of the vehicle manufacturer in New Zealand.
Read about the results of corrosion testing of bioethanol blended fuel on aluminium engine components (July 2009).
Where else can I use bioethanol-blended petrol?
Bioethanol-blended petrol can be used in almost any petrol engine, from lawn mowers to generators. There is one precaution you need to take: don't leave bioethanol-blended petrol in the tank for longer than two months, as it may absorb moisture from the air. Looking after the fuel this way is just the same as you should do with ordinary petrol. You can also check the vehicle or equipment handbook, or check with the supplier.
When NOT to use bioethanol-blended petrol
Bioethanol-blended petrol must not be used in:
- Aviation applications, such as microlights (due to cold temperatures and condensation risks at altitude)
- Marine applications, such as boats (due to the higher risk of contamination with water).
Useful tips
When first using bioethanol-blended petrol in your car, follow these simple, low-cost tips to get the best out of your car. To make it as easy as possible, you can get these done when you next take your car in for a service:
Check for water
Older vehicles should be checked for excessive water at the bottom of the fuel tank. A qualified mechanic or other authorised person can easily check this for you.
The first fill should be a big fill
Make your first fill with bioethanol-blended petrol a big fill to absorb any existing water in your tank.
Change your fuel filter
If your fuel filter hasn't been changed recently, it should be changed after the first few fills of bioethanol-blended petrol. Bioethanol-blended petrol cleans your fuel tank so changing the filter will help remove any debris allowing your car to run as smoothly as possible.
More information
- Using biofuels in New Zealand: where to buy them and how to know if they are sustainably produced
- Download the biofuels factsheet
- More information on specifications and regulations concerning biofuels.
- Technical information, including research into biofuels [EECA website]
