( CNN ) -- When it comes to the environment , aviation has a rather dirty reputation . The industry produced 689 million tons of CO2 in 2012 , according to Air Transport Action Group ( 12 % of global transportation 's carbon dioxide emissions ) -- a number that is sure to grow as global demand for flight continues to skyrocket . `` Aviation will double in size worldwide in the next two decades , and if we 're not able to provide a sustainable means to fly , we will create a ceiling for growth in the industry , '' says Ignaas Caryn , director of innovation at KLM Royal Dutch Airlines . As a result , it looks like the aviation industry is ready to green up its game . In January , Boeing announced a new initiative to build a biofuel supply chain in the United Arab Emirates , as well as research it 's conducting into biofuels made from salt water-consuming desert plants . Airbus has similarly partnered with local producers and airlines to sniff out sustainable alternatives to fossil fuels . To name just a few partnerships , the airplane manufacturer teamed with Virgin Australia Airlines to to produce sustainable aviation fuels from eucalyptus mallee trees in Australia . Airbus has also joined other aerospace companies in launching the ITAKA initiative , a collaborative project funded by the European Union to produce and test the use of sustainable jet fuel . Frederic Eychenne , Airbus ' head of new energies , notes that no single crop will do the job for biofuels , and that to achieve true sustainability , biofuel -- like food -- is best when it 's locally-sourced . `` Different countries grow different crops . They have different refineries in place . Sustainability is n't just about reducing emissions in the air . We have to consider the whole life-cycle in terms of production , '' he notes . Going the distance . Long-haul flights make up 80 % of aviation 's CO2 emissions . As a result , cutting down the carbon footprint for these flights is extra important . In May , KLM took the first step and launched a new series of flights traveling between Amsterdam and Aruba that use a 20 % biofuel blend . The flight is part of KLM 's short-term goal to integrate 1 % of biofuel into all its flights by 2015 . The main barrier to using biofuel on a larger scale , says Caryn , is the price . `` Today , bio jet fuel is still three to four times more expensive than fossil fuel , because there 's no continuous production . There 's a demonstrated hole in the value chain , '' he notes . To solve the problem , in 2010 KLM became a joint founder of SkyNRG -- a major supplier of eco-efficient jet fuel . `` We believed the development of bio jet fuel was important , and that we could n't keep it within the boundaries of KLM , so we decided to come up with a new company . In the last five years , SkyNRG have supplied approximately 25 airlines , '' he says . SkyNRG is also working with airlines and airports around the world to create bioports -- or supply chains of sustainable jet fuel -- in a bid to ultimately bring down the price . `` With an increase volume , we could see price parity within the next ten years , '' says Caryn . Other steps . Depending on the source of jet fuel and how it 's cultivated , Caryn estimates using biofuel could reduce carbon emissions between 50 and 80 % , depending mainly on the feedstock and conversion process . He notes that there are other methods currently in use to drop that percentage even further . `` The way of taking off , the way of landing , and the route you choose to fly can all impact emissions , '' he notes . Planes that make a continuous ascent or descent when landing or taking off -- instead of the more traditional `` step-down '' approach -- he says burn less fuel . Eychenne also notes that Airbus is slashing emissions by switching to more innovative materials . `` We use a lot of composite materials now , which are lighter , and by bringing the weight down , you bring fuel consumption down , '' he says .
KLM recently flew from Amsterdam to Aruba using sustainable jet fuel . The 10-hour flight was the longest to ever use biofuel . KLM is founding partner of SkyNRG , a supplier of sustainable jet fuel .