Biofuels are one form of Bioenergy, are generally ethanol and biodiesel, and are an alternative to fossil fuel - produced by using some form of organic material, like plants, wood by products, animal waste, animal fats and algae to produce fuel. According to Arena, biofuels production is projected to increase 10-fold globally by 2060, making it potentially a major player in decarbonisation of the fuel worldwide.
Most people are aware of biofuels in connection with their cars and for transport fuels, there are two main types of biofuels used in Australia: ethanol and biodiesel. It can be a little confusing because the fuel seen at petrol stations is a mixture of more traditional fossil-fuel based fuel and biofuel.
Most of us are familiar the common Ethanol blended petrol (EBP) or E10 fuel as it is the one you see at the petrol bowser. It is a blend of unleaded petrol and up to 10 per cent ethanol. You might also have seen E85 fuel, which contains up to 85 per cent ethanol, but is generally only suitable for purpose-built vehicles.
Biodiesel contains a blend of diesel and either 5 or 20 percent of fatty acids from vegetable or animal tallow. These blends are called B5 or B20. Not all diesel vehicles are compatible with biodiesel, and you should check with the manufacturer if your vehicle is suitable for use with biodiesel.
While biofuel is seen as a major player in the decarbonisation of the transport sector, the issue of its sustainability is dependent upon what it is derived from, how it is harvested and manufactured and what is displaced in order for it to grow. Where biproducts are used in its manufacture, the debate is more straightforward, as much -of this rescued material would have been destined for landfill. (Molasses, for instance, is used extensively to make biofuel in Australia and it is a by-product of sugarcane.)
APART FROM SUGARCANE, OTHER FOODS COMMONLY USED FOR BIOFUELS ARE PALM OIL, RAPESEED OIL (CANOLA), WOOD AND SOYBEANS.
PRETTY MUCH ANY PLANT CAN BE TURNED INTO A BIOFUEL, ALBEIT AT DIFFERENT COSTS PER UNIT OF FUEL OUTPUT.
Plants for fuel seem like an ideal solution – carbon sequestration, preservation of unrenewable fossil fuels and mitigating the issues that go with mining. But the issue with plant-based biofuels is that the plants have to be farmed in the first place. The use of plants like sugar cane and corn to feed our appetite for fuel means we’re talking about lots of land and that starts to bring the sustainability question into account as land is cleared to grow crops like palm oil.
There are other impacts of using traditional food sources for fuel:
In the end, biofuels are still substantially more sustainable than fossil fuels. For some time, algae was seen as a potential new, low impact biofuel, but it's utility has proven to be elusive.
The marine algae seaweed (giant kelp) however, is emerging as a strong contender. Growing kelp doesn’t require land, fresh water or fertilizer. Giant kelp can grow over a foot per day under ideal conditions is also an excellent CO2 sequesterer.
For more information on the scale up of the environmentally responsible commercial farming of seaweed to provide food, feed and bioproducts, check out the Australian Sustainable Seaweed Alliance (ASSA).