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Biofuels: How "Green" and Sustainable Are They?
Once hailed as "green fuels", the first industrial-scale biofuels have come under scrutiny as people question the true amount of energy used in their production and their impact on food crops.

BiofuelsA fuel produced from plant or animal matter. There are currently two types of biofuel... were developed to meet a variety of objectives, such as promoting agricultural resources, increasing national energy independenceThe ability of a country or region to meet all its energy needs without having to import primary or final energy. and ensuring steady revenues for farmers. They first appeared in the 1970s in Brazil and the United States – both of which continue to be big producers and consumers – before migrating to Europe in the 1990s.
With growing concern over climate change toward the end of the 20th century, biofuels began to emerge as a less carbon-intensive alternative to petroleum-based fuels. In 2003, the European Union (E.U.) began encouraging Member States to set binding targets for the use of biofuels alongside their non-renewable counterparts. Then in 2009, it went one step further by requesting that by 2020 Member States source 10% of all energy used in the transportation sector from renewable sources (primarily biofuels but also "green" electricityForm of energy resulting from the movement of charged particles (electrons) through a conductor... and biogasA product of the methanation (anaerobic digestion) of organic waste... ).
However, experts and environmental groups soon began to question several aspects of the biofuel production process1, such as:
- Energy efficiencyIn economic terms, energy efficiency refers to the efforts made to reduce the energy consumption of a system... and CO2See Carbon Dioxid emissions. Every step in the biofuel production process requires energy, be it for the fertilizers and pesticides used on the crops, the machinery used for conversion, the vehicles used for transportation, etc. Each successive step increases the carbon footprintThe carbon footprint (also known as greenhouse gas inventory) of a good or service measures the impact human activities have on the environment ... , which must be taken into account at the end of the value chain.
- Food versus fuelFuel is any solid, liquid or gaseous substance or material that can be combined with an oxidant... , or the balance between food crops and energy crops. The more farmland used for biofuels, the greater the threat to food production, particularly in regions prone to shortages. Already more than two billion people worldwide live in poverty, and the global population is growing fast.
- Impact on land use. Allocating vast areas of farmland to biofuel crops can trigger rural flight, accelerate deforestation (as in Indonesia following the development of oil palms) or push farmers into what were previously forests and wetlands, thereby eliminating major sources of biodiversityRefers to the natural diversity of living organisms. It can be measured through the study of species, genes and ecosystems. and highly effective carbon sinks. This process is referred to as indirect land use change (ILUC).
E.U. Sustainability Criteria
Second-generation biofuels reduce the risk of competition with food crops.
In Europe, the debate was – and continues to be – particularly heated among elected representatives, environmental groups, farmers and industry representatives.
In 2009, the European Union introduced "sustainabilitySustainability indicates a state that is sustainable or reasonably manageable over the long term. criteria" for biofuels consumed within its borders. To comply, biofuels had to achieve greenhouse gas (ghg) Gas with physical properties that cause the Earth's atmosphere to warm up. There are a number of naturally occurring greenhouse gases... savings of 35% compared with petroleum-based fuels (rising to 50 % in 2017) and meet certain land use conditions2. A complete change of tack followed in 2012, when the E.U. proposed a 5% cap on crop-based fuels (i.e., first‑generation biofuels) in the transportation energy mixThe range of energy sources of a region. . Then in 2015, it introduced a new restriction by limiting biofuels produced from food crops to 7% within the E.U. Finally, in May 2016, the European Union abandoned its 2009 rule, replacing the 10% renewable energyEnergy sources that are naturally replenished so quickly that they can be considered inexhaustible on a human time scale... target for transportation with cross-sector, E.U.-level targets from 2020 onward. Under severe criticism from biofuel producers, the European Union will clarify its position on this highly sensitive issue some time in 2016.
Despite these difficulties, biofuels are still considered essential to reducing CO2 emissions in the transportation sector, particularly in the aviation and trucking industries. The International Air Transport Association (IATA) has vowed to increase the use of biofuels to 10% of total fuel consumption industry-wide by 2017. And the road transportation industry is currently looking for lower-carbon truck fuels – both biofuels and gaseous varieties.
On the same topic
Benefits of Second-Generation Biofuels
Second-generation or "advanced" biofuels, which are produced from lignocellulose or residual oil, would offer the indisputable advantage of not competing with food crops.
However, they do present some drawbacks, such as:
- Significantly higher production costs than first-generation biofuels.
- Appropriation of "residues" that are currently already used as fuels or in animal feed.
- Use of straw and other farming waste that is today buried to improve soil quality and store carbon.
Sources :
(1) See FAO report
(2) For an overview of application in France (French only)