Biofuels: Advantages and Challenges

A biofuel is produced from biomass. It comes from the transformation of vegetable or animal’s raw materials. Since biomass can technically be used directly as a fuel (e.g., wood logs), some people use the terms biomass and biofuel interchangeably.

The use of biofuels has many advantages, including environmental ones. Primarily, biofuel serves as a complement - and longer-term substitute - for fossil fuels. According to some studies and estimations, biofuels allow to decrease transportation environmental effects and thus improve air quality by reducing greenhouse gas (GHG) emissions, mainly carbon dioxide (CO2).[1] Indeed, cultures serving to produce bioenergy can reduce or offset GHG emissions by eliminating CO2 from air when growing. Biomass allows to store CO2 in crops and soil.[2]

However, this information must be considered carefully for multiple reasons such as:

The different generations of biofuels. Indeed, GHG emissions decrease is highly dependent on the type of land used to produce biomass for biofuel.
The effect of using land for biofuel production on food security, malnutrition, etc.
The intensive agriculture production to ensure biofuel manufacturing leading to intensified acidification, eutrophication and/or ozone depletion compared to fossil fuels production.

In this post, we will start by presenting the biofuels types and generations then we will finish by discussing the challenges facing biofuels production, their effect on climate change, and the certifications to be implemented to optimize these effects.

Biofuels types

Three generations of biofuels can be distinguished:[3]

The agrofuels:

This is the first generation of liquid biofuels produced from agriculture (beet / sugar cane, wheat, corn, potato, rapeseed and sunflower oils). These biofuels are now manufactured on an industrial scale. For instance, the majority of biofuels produced and consumed in France are agrofuels.

The main agrofuels produced and used are:

Biodiesel made from rapeseed, sunflower, soybean or palm oil: Mixing the oils with an alcohol in the presence of a catalyst (NaOH or KOH) allows to obtain fatty acid esters (FAE). These esters are then incorporated into the diesel at different percentages ranging from 7% (B7 diesel) up to 30% (B30 diesel). In 2018, B100 diesel (100% fatty acid methyl esters) was approved. In France, the Avril group recently launched a B100 diesel called Oléo 100 made from rapeseed oil.

Bioethanol resulting from an industrial process involving the fermentation of sugars contained in plants (sugar beet, wheat or corn starch, grape marc). Bioethanol is incorporated into gasoline, directly or in the form of ethyl-tertio- butyl-ether (ETBE). In 2017, in France, 7.5% of the energy contained in gasoline was of renewable origin, 3.4% in the form of bioethanol and 2.3% in the form of ETBE.
Biomethane: This is a gaseous biofuel. It is obtained through an anaerobic digestion process from organic waste (livestock effluents, wastewater, agricultural / industrial / municipal waste) under the action of microorganisms (bacteria) in the absence of oxygen.

The majority of studies have found that the production of first-generation biofuels from crops led to GHG emissions reduction by 20 to 60% compared to fossil fuels and depending on the crop type. The implemented Life Cycle Assessments (LCA) consider that the most efficient systems are used and exclude carbon emissions from land use.[4]

The advanced liquid biofuels – Second and third generations

They can come from animal fats (1.2% of FAME/Fatty Acid Methyl Esther integrated into diesel in France in 2017) or used edible vegetable oils (4.3% of FAME integrated into diesel in France in 2017). This type of biofuel is the subject of relatively modest industrial exploitation to date.

The second-generation of biofuels:

These are fuels made from thermally or biochemically transformed lignocellulose.
The production of these biofuels has still not reached the industrial stage.

The third-generation biofuels:

These are fuels made from algae.
The manufacture of these biofuels is still at the research stage.

Even if their use at commercial level remains insignificant, the second generation of biofuels generally allow to reduce by 70 to 90% GHG emissions in comparison to fossil diesel and gasoline. It must be noted, that also in this case GHG emissions related to land use are excluded in the LCA.[4]

Biofuels – The challenges

Despite the advantages of biofuels and their capacity to replace fossil fuels, serious inconvenient and challenges face their production and industrialization: [5]

Abuse of biomass production and mismanagement.
Burning peatlands to prepare biomass which generates considerable GHG emissions.
Biofuel production may also compete with food production. Indeed, the growing use of food crops as a source of fuel may lead to malnutrition and hunger intensification.[6]

To answer these challenges, the European Union implemented a biofuels directive in 2003. This directive was followed by a comprehensive biofuels’ legislation in 2009 - the "Renewable Energy Directive - RED" and the "Fuel Quality Directive" amendments.[7],[8]

Also in the United States, the Renewable Fuels Standard, created under the Energy Policy Act of 2005, has provided a powerful policy driver for the adoption of biofuels by the US market.

European directives have defined sustainability criteria for biofuels as well as tools for monitoring compliance with these criteria by economic operators. EU Member States can only consider certified sustainable biofuels. In European law, 2 categories of sustainability criteria are taken into account:

Quantitative criteria linked to GHG emissions: biofuels and bioliquids must reduce GHG emissions by at least 50% over the entire "well-to-wheel" cycle.
Qualitative criteria linked to cultivated land: the production of raw materials used to produce biofuels is subject to the aid allocation rules of the Common Agricultural Policy (CAP) and to good agri-environmental conditions. Raw materials cannot come from land rich in biodiversity or with high carbon stock.

In this context, several challenges must therefore be met:

The production of fuels from plant or animal products should therefore not be synonymous with environmental and societal damage (food and water scarcity, deforestation, climate change).
In addition, multiple types of raw materials should be used to feed the biofuel market to avoid over consumption of only one type of raw material / crop.

All of the above criteria apply to the entire production and distribution chain of biofuels. The economic operators concerned by these rules are many and diverse (farmers, traders, refineries, service stations, etc.):

Producers or collectors of raw materials.
Actors participating in the storage and / or marketing of raw materials.
Raw materials transformers.
Producers and sellers of biofuels.
Actors who incorporate biofuels into final fuels.
Importers of fuels (containing biofuels) and those who distribute them / put them for consumption.

All these actors must be able to demonstrate that the sustainability criteria are met. For this purpose, they have the choice between 3 systems:

A bilateral or multilateral agreement concluded by the European Union with third countries.
A national system set up by a European Member State.
A voluntary labeling or certification system. It is set up by economic operators with other interested parties. This system is validated by the European Commission. Royalty as well as certification fees are paid by the producers adhering to this system. The certificate issued by a voluntary scheme recognized by the European Union is valid and sufficient in all Member States. The latter do not have the right to demand further evidence of compliance with the sustainability criteria.

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