Greener & Cleaner

Necessity being the mother of invention, humanity is once again poised to take a giant leap in the field of aviation in respect of alternative sources of jet fuels in the form of sustainable biofuels

Difficult circumstances invariably result in ingenious solutions. Owing to unsustainable fuel prices and growing environmental concerns, two landmark developments have been witnessed in the recent past in aviation history. While Pratt & Whitney has developed the less noisy GTF engine that achieves higher thrust with substantially lower fuel burn and reduced emission, the National Research Council of Canada (NRC) flew its Falcon 20 on October 29, 2012, at 30,000 feet with 100 per cent unblended biofuel.

Analysis of the data collected during the flight revealed that biofuel was cleaner and was as efficient as conventional fuel. There was significant reduction in emissions, aerosol by 50 per cent and black carbon up to 49 per cent. The success of this historic flight is not only a significant milestone for the aviation industry but also a major step towards advancing sustainable sources of renewable energy.

An alternative for the aviation industry

The global aviation industry has grown rapidly over the last two decades. Today, it employs over 30 million people and contributes handsomely to the gross domestic product of the world. The global aviation fuel market is currently worth around $140 billion a year and growing. While the socio-economic benefits of the growth of the aviation industry have been enormous, the environmental costs in the form of carbon emissions have also been heavy. While the high cost of aviation fuel is a subject of major concern for aircraft operators, the aviation industry’s share of greenhouse gas emissions currently at two per cent is estimated to rise to three per cent by 2050.

Biofuels as an alternative to fossil fuels would be attractive as these would reduce carbon footprint and would be the preferred option for the aviation industry if the aircraft operating costs are low. Thus there is incentive for all stakeholders in the aviation industry to develop low-cost biofuels as an alternative to fossil fuels for the aviation industry.

Virgin Atlantic demonstrated the effectiveness of biofuel and jet fuel blend on a London to Amsterdam test flight in February 2008. KLM used biofuel in a commercial flight from Amsterdam to Paris in June 2011 carrying 171 passengers. The resolve in developing biofuels as an alternative to aviation fuel has only strengthened. The success of these efforts and endorsement from engine manufacturers led to biofuels being approved for commercial use in July 2011. While active testing of the differently sourced biofuels as an alternative aviation fuel is still being undertaken, some countries have set ambitious targets for 2020. The ‘Farm to Fly’ programme in the US has a target of producing one billion gallons of aviation biofuel by 2018. Boeing too is betting heavily on a bright future for aviation biofuels.

The aviation industry’s need for biofuels has also been accentuated by the fact that aviation is being increasingly included in carbon tax and carbon emission trading programmes. The European Union Emissions Trading System being the biggest such initiative, values biofuels as ‘zero emission source’. While the Internationd Civil Aviation Organisation (ICAO) has an ambitious target of carbon neutral growth (CNG) from 2020, a recent study by Professor David Lee of Manchester Metropolitan University, United Kingdom, stresses on the importance of market based mechanisms like emissions trading to achieve this goal.

Production of Biofuels

While first-generation biofuels are produced from renewable biological resources like plants and are used for various purposes including heating and cooking, sources of second-generation biofuels are those that can be used in aviation and do not compete with food supplies. Ethanol, derived from plants rich in sugars, can be used as an additive or petroleum substitute. These types of fuels are known as first-generation biofuels but they do not meet the performance and safety standards needed for modern jet engines. Also, these are produced at the expense of consumption-driven food crops and contribute to deforestation and depletion of groundwater resources. However, bio-derived oils are sourced from plants such as jatropha, algae, camellia and halophytes, which do not compete with human food crops and when processed into high quality aviation fuels, are called second-generation biofuels.

In order to develop sustainable second generation biofuels for the aviation industry, it has to be ensured that these crops are produced on a large scale and with negligible environmental impact. The crops should be fast growing plants and not adversely impact biodiversity. They should not be grown in productive arable land and must result in lower carbon footprint. Sustainably produced biofuels will provide enormous environmental benefits in terms of an estimated 80 per cent reduced CO² emissions in comparison with fossil fuels. Also, the unpredictability of crude oil price and geopolitical situation affect not only the operating costs but also has a potential to create production uncertainty or supply disruptions. Since biofuels can be produced across the globe as against the limited areas of availability of fossil fuels, the sustainable biofuels would be able to cater to the demand and supply in diverse geographic locations. As second-generation biofuel crops can be grown even in deserts and saltwater, the economic and social benefits are likely to be enormous especially for developing countries which have large unviable and non-arable land parcels.

Sustainability

While biofuels are crucial for the aviation industry and governments in terms of energy security and economic/environmental goals, there are concerns about the longterm sustainability as a result of land use change, biodiversity impacts, water consumption and food security. An important aspect in the sustainability of the biofuel industry is also the economic constraint faced by the airlines, thus impacting their ability to invest and support the biofuel industry. However, despite these constraints, aviation biofuel market is likely to develop at a faster pace to emerge as an alternative energy source for the aviation industry, mainly due to the inherent benefits and the sense of urgency. Nonetheless, despite the necessity as well as importance of biofuels for the aviation industry, viability of biofuel industry would depend upon sustainability of the technology, processes and methods including balancing of socio-economic considerations. Sustainability issues would have to be addressed by ensuring the use of non-food crop resources to produce aviation biofuels, without depriving the common man of valuable food, land and water resources.

Due to climatic conditions and suitability of the feedstock, production and supplies, it is most likely that aircraft in the future would be powered by a combination of biofuels and jet fuel. The challenges to the successful production and usage of biofuels in the aviation industry are in the regime of economic viability, technical compatibility and sustainability. It would also be necessary to ensure that biofuels meet safety requirements, withstand a range of operational conditions and enable the aircraft to operate efficiently over its complete performance envelop. The biofuel industry would have to respond to the challenges successfully for the acceptance of biofuels as alternative aviation fuel by the aircraft manufacturers as redesigning of engines to suit biofuels may not be a viable proposition.

Economic viability can be ensured with economies of scale and improved production technologies so as to be able to compete with the petroleum-based fuels. Biofuels can provide immense economic opportunities to many a developing country and marginal communities possessing large tracts of unproductive non-arable land. As per analysts, the viability of the biofuels can be ensured if one per cent of the world’s jet fuel is substituted by biofuel. Thus, with the current annual jet fuel consumption of around 70 billion gallons, as little as 0.7 billion gallons of biofuels (which may also be used in the ratio of ten per cent biofuel with 90 per cent jet fuel) would make it an economically viable proposition. While about 85 per cent of biofuel production costs relate to the cost of feedstock, this cost is likely to reduce drastically with the production of large quantities of feedstock with improvement in processing and harvesting technology. As discussed earlier, if the ambitious industry and country biofuel targets are to be achieved, the sustainable feedstock must be produced on a large scale. If everything goes as per the plan, it is estimated that by 2020, the cost of biofuels would be closer to the cost of jet fuel.

The history of mankind is witness to many milestones, which were unthinkable before. Necessity being the mother of invention, humanity is once again poised to take a giant leap in the field of aviation in respect of alternative sources of jet fuels in the form of sustainable biofuels. Governments as well as the aviation industry have an equal stake in ensuring a sustainable and economically viable biofuel industry for the common good of all stakeholders since fossil fuels are not only becoming scarce and expensive but also a major source of environmental degradation.