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Article updated on 18/02/20 by Kerry Taylor-Smith
Biofuel is a fuel produced from renewable biomass material, commonly used as an alternative, cleaner fuel source to burning fossil fuels. Biofuels are low in carbon intensity so they don't directly affect global warming in fact, it is suggested that biofuel formulations can remove materials like logging waste and cooking oil from the waste stream.
As of 2010, the worldwide production of biofuel reached 105 billion liters, which is a 17% increase from the year previous. Biodiesel contributed to nearly 2.7% of total fuel consumption for road transport in 2010, which is mainly due to the contribution of biodiesel and ethanol.
The total amount of ethanol produced was 86 billion liters in 2010 with Brazil and the United States being the world's largest producer accounting for 90% of production. The European Union is the world's largest producer of biodiesel accounting for 53% of production worldwide.
Types of Biofuels
The two most common types of biofuels used today are ethanol and biodiesel.
Ethanol – is a flammable and renewable liquid produced by the fermentation of grain or from advanced technology such as agricultural waste, wood chips, and waste paper. Ethanol can also be prepared through gasification which uses high temperatures or low-oxygen conditions for the conversion of biomass into synthesis gas. The synthesis gas can then be converted into ethanol.
Ethanol is combined with gasoline for increasing octane and reducing carbon monoxide emissions. Certain vehicles run on E85 which is an alternative fuel with high ethanol content. Ethanol releases around 15% less greenhouse gas emissions when burnt than gasoline. Recent developments in cellulosic ethanol enable the production of ethanol from waste cellulose such as food by-products, scrap wood and non-food plants like switchgrass.
Biodiesel - Biodiesel is produced through a combination of alcohol with recycled cooking grease, animal fat or vegetable oil. Recently, scientists have genetically engineered algae and bacteria strains to generate biodiesel. It is a highly combustible liquid that burns readily upon mixing with petroleum-based diesel fuel. During the production of biodiesel, glycerin is produced as a by-product, which is highly combustible. Biodiesel can be used as a renewable alternative for diesel engines - however, some studies show that biodiesel produces more harmful emissions like carbon monoxide and particulates.
Biobutanol - is another type of fuel which is less known, but is a promising alternative. It is an isobutanol derived from algae or bacteria just like biodiesel, or by fermentation of biomass like ethanol. This fuel can be directly used in standard gasoline engines without any modifications. Due to its high octane levels, biobutanol reduces any loss in fuel mileage.
Benefits of Biofuels
The following are some of the advantages of biofuels:
- Unlike fossil fuels, biofuels are produced from renewable resources.
- There are less pollutant emissions from biofuels. Ethanol reduces carbon monoxide emissions as it ensures complete combustion.
- Biofuels do not contribute to global warming as carbon dioxide released, is taken up by their feedstocks.
- Biofuels are cost-effective when compared to fossil fuels.
- Unlike other alternative energy sources like wind and solar energy, a relatively small amount of biofuels can produce a significant amount of energy, which is best suited for transport applications.
Applications of Biofuels
Some of the applications of biofuels are listed below:
- Transportation including engines in chainsaws and lawnmowers, diesel cars and trucks, aviation and off-road equipment like those in heat production, construction, forestry, mining, and agriculture.
- Biofuel cells have great potential to power implantable medical devices such as glucose biosensors.
- It can be used to remove organic compounds from the waste stream without costing a fortune.
- It can be used as a heating fuel commonly referred to as “bioheat” for heating buildings.
Future of Biofuel
Biofuel is a safe alternative for existing vehicle engines. Biofuel technology is capable of reducing greenhouse gas emissions and for the usage of fossil fuels. It can create job opportunities that could significantly improve the local economy. A rapid increase in biofuel production over the past few years has prompted an international policy to encourage low carbon policies.
Studies show that the production and consumption of biofuel will likely double with increasing biofuel demand from $82.7 billion in 2011 to $185.3 billion by 2021. Researchers hope that the massive increase in the production of biofuels could change the geopolitical and industrial landscapes by meeting consumer needs in ground, maritime and aviation fuel markets. Furthermore, increasing feedstock consumption will likely boost the global biofuel trade.
References and Further Reading