While there is considerable controversy regarding the Greenhouse gas emission-related benefits of biofuels, a number of air lines, notably United, are starting to use a “natural” jet fuel produced by a process patented by UOP. The fact that this biofuel is produced from waste rather than from crops is significant as no hydrocarbon-related fuels or chemicals are used for the specific purpose of making the fuel. While carbon dioxide is, of course, emitted into the atmosphere when the biofuel burns, this carbon can be assumed as again being absorbed into plants through photosynthesis, completing the cycle, so that no net carbon dioxide is emitted as would be the case for crude oil-based jet fuel. UOP claims that use of its bio jet fuel can reduce GHG emissions by 65-80 percent
The UOP Green Jet process had its origins in DARPA-conducted research to produce military jet fuel from renewable sources. In the basic process. natural oil or greases and deoxygenated and isomerized to produce green Diesel. With selective cracking, jet fuel is produced.
AltAir Fuels will retrofit part of an existing petroleum refinery to make 30 million gallons per year of advanced biofuel from non-edible natural oils and agricultural wastes. This fuel can blend up to 50% with fossil kerosene. Fulcrum Bioenergy has developed a process that turns municipal waste (household trash) into sustainable aviation fuel and will supply United Airlines, which has invested in Fulcrum’s refinery. Fulcrum’s president claims it can produce bio jet fuel for around one dollar per gallon – half the cost of what United paid for jet fuel last year. British Airways is in a joint venture to build a biofuels refinery near Heathrow airport. Cathay Air Lines and Alaska Airlines are likewise engaged in a plan to make and/or blend natural jet fuel into traditional fuel.
A Middle East firm Petrixo Oil and Gas claims it will use the UOP process to produce one million tons per year of biofuels at a cost of $ 800 million in the United Arab Emirates. (Feedstock source not identified).
Behind these developments is a government push to reduce airlines’ carbon emissions. The Obama administration has set out guidelines to achieve key reductions, recognizing that airline GHG emissions are rising at a fairly rapid rate.
So, let’s put this in context. The good news is that it is now apparently possible to make blendable jet fuel economically from natural materials and, more interestingly, from municipal waste and crop wastes. And there is a net carbon benefit in doing this. There is really no bad news, except for the fact that there are immense logistical challenges in making biojet fuel production a major industry. While it was quite easy to develop a “gasohol” industry from corn, given the fact that corn was already available in huge quantities in silos and could easily be diverted to fuel instead of foodstuff use. This would be impossible to do with municipal waste or even agricultural waste, where many thousands of tons would have to be collected from many sources and brought to refineries. greatly increasing the production costs and the carbon emissions. For specific locations and situations, however, there is an economic and carbon footprint-related reason to build a certain amount of biojet fuel capacity.