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Biocombustibles para volar más limpio

Biofuels for cleaner flying

The Aviation Industry has set itself the target to halve air travel CO2 emissions, which currently account for 2% of the world’s total emissions, by 2050. Biofuels are going to play a key role in achieving this. Biofuels are already being developed using non-food crops such as camelina. In the near future, we will see large-scale production of biofuels using microalgae.

Every year, the aviation sector transports 2,200 million passengers across the globe which is an essential element of a global society. According to IATA (The International Air Transport Association) estimates, in 2050 there will be 16,000 million passengers. The constant growth of traffic is presenting the aviation industry with the challenge of catering for this growing demand whilst also cutting emissions.

The formula for achieving cleaner flying will come from more efficient planes with improved engines and turbines, the use of lighter materials for aircraft construction so as to cut consumption, as well as from the intensive use of biofuels which mitigate carbon footprint. Airlines, aircraft manufacturers and energy companies are all involved in this technological innovation effort.

First Spanish Biokerosene Flight

Primer vuelo español con bioqueroseno
In Spain, Repsol and Iberia took the initiative and last October conducted the first biokerosene-powered flight. An Airbus 320, which Iberia normally uses for flights between Madrid and Barcelona, was fuelled with a combination of 25% biofuel and 75% regular kerosene.

The biokerosene used for this flight was based on camelina oil, an inedible oilseed plant. Repsol was responsible for the fuel sourcing, high production yield analysis, distribution and logistics. Flying using this biofuel did not require any adaptation of the jet engines and it achieved an estimated 1,500 kg reduction of CO2 emissions.

"The biokerosene that we are using is capable of achieving optimal performance from the propulsion of the plane", announced Pedro Fernández Frial, Repsol's Executive Director of Downstream at the first biofuel flight, who believes that "the work being done on biofuels is opening up a very promising future".

At the same biofuel flight event, Manuel López Colmenarejo, Iberia's Director of Corporate Affairs explained that airline companies need biofuels "that are sustainable, competitively priced, produce far lower net CO2 emissions throughout their entire productive cycle and can be used with most jet engines without needing any adaptations. The biofuel derived from camelina used in the flight "fulfils all these criteria".

Sustainable Biofuels for Aviation

Camelina is an herbaceous oilseed crop that produces a large amount of oil and that "can be grown in temperate and cold climates such as the Spanish climate", says Fernando Temprano, Repsol's Director of Technology. Its ability to adapt to marginal agricultural land and its resistance to frost and drought "mean we will have a greater range of raw materials to use to produce bioenergy".

Second generation biofuels such as camelina-based biofuel are considered sustainable because they are made from plants that do not compete with food crops, either for land or for resources such as water.

Another plant that is being developed to produce 2nd generation biofuel is jatropha. Some airline companies have already conducted flights powered with this biokerosene and Repsol has plans for large scale development of this crop. "We envisage an estimated timeframe of 3-4 years to produce large quantities of this oil because this plant obviously takes a long time to grow", explains Temprano.

The oil extracted from these plants is processed through a refining process known as hydrotreating, which involves subjecting these vegetable oils to a chemical reaction with hydrogen and a catalyst at high temperatures to create hydrocarbons that have exactly the same chemical composition as fossil based kerosene. This means it is possible to fuel jet engines without the need to make any alterations and its plant origin means that overall CO2 emissions can be cut.
The second generation biofuels do not compete with food crops, either for land or for resources such as water

From trial flights to large scale production

Carga de biocarburantes
"The most important challenge is ensure that these current experimental productions become elaborate industrial processes that can supply the market", says José Antonio García Cabañas, Head of Aviation Technical Assistance at Repsol.

To date, in most flights conducted worldwide, the biofuels used were blends of varying proportions of biofuel and traditional kerosene. However, there is no technological reason that aviation fuel could not be 100% biofuel. To date, demand has not justified production on an industrial scale.

García Cabañas considers Iberia and Repsol's biofuel flight as the "first step towards a new market that is opening up in Europe as of 2012, following the introduction of new standards to limit aviation CO2 emissions" As of 1st January, airline companies have to purchase and submit emission allowances for all flights departing from or arriving at EU airports, which means that "there will be widespread demand from airline companies for this type of fuel".
"It's still too soon to say when this type of product will be widely available", continues García Cabañas, "although prospects look bright for the coming five years". The IATA, an umbrella organisation of the main airline companies across the globe, claims that in 2015 biofuel will account for 1% of the total fuel used and by 2020 this will reach 15%.

Microalgae: The new generation of biofuels

The growing demand for biofuel will not be met by extracts from crops such as jatropha or camelina alone. Experts are predicting that the bulk of reserves for aviation biokerosene will come from algae. "We are also developing 3rd generation fuels such as microalgae-based fuel, which are living systems of plant origin that grow faster, produce more oil and yield more than soil", says Fernando Temprano.

Repsol has an ambitious biofuel production programme using microalgae. Based on research conducted at The Repsol Technology Centre, it will start to be produced on a semi-industrial scale in the near future.

Although progress in this field is fast, Temprano points out however that there are still some challenges to be overcome. "We are making a huge commitment in terms of technology to master the cultivation of this crop and control the production of energy so that it is economically competitive".
Repsol has an ambitious biofuel production programme using microalgae
Last updated: January 2012