Bio Jet 1
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It's largely a show, but alternative fuels are hugely important to aviation's future. We are lucky that turbine engines can accept and work well with a variety of fuels. It will probably be shown that jets can uplift jatropha based fuel from New Zealand on one leg then an algae based fuel from Australia on the next. And they're a lot easier to store than the hydrogen we'll one day use.
Join Date: Dec 2001
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Interesting but possibly impractical...
Green fuel for the airline industry - tech - 13 August 2008 - New Scientist
Green fuel for the airline industry - tech - 13 August 2008 - New Scientist
With over 20 years' production experience, Ben-Amotz is convinced that the maximum practical yield is 25 grams of biomass per square metre per day, of which 40 per cent might be oil. That equates to about 36 tonnes per hectare per year, meaning that to replace current jet fuel consumption would take about 65,000 km2, roughly the area of Ireland.
Join Date: Jul 2005
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Is there any realistic way that Members of the European Parliament (MEP's) could be productively converted to Bio Fuel? They produce more hot air than a current high bypass engine anyway! Plus it would dove tail in nicely with the convert Belgium plan. 
P.S. Could we re-instate Mandelson into the EU parliament before implementation? Please?
P.S. Could we re-instate Mandelson into the EU parliament before implementation? Please?
Join Date: Oct 1999
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Putting the yield and sustainability debates aside (cwatters is not wrong), there are several key technical issues - the most important in my opinion being cold flow properties for FAME/biodiesel and various other issues such as sticking on standing and effect on catalytic converters for Bioethanol. While the biofuel beads and sandals brigades would have you believe otherwise, there are very real technology limits for the use of biofuels - one of the reasons that Volvo believe that B7 (7% Biodiesel in Diesel) is currently the practical limit with normal engines even though B100 is happily on sale in some parts of Europe.
For aircraft paraffins I suspect that the limiting factor will be lubricity - and that is related to the very low levels of Sulphur in Biofuels. There have already been fleet fuel pump failure incidents (NZ comes to mind) when severly hydrotreated conventional kero caused failures in the domestic fleet (but not the longhaul fleet which of course fills up all over the world).
Another big issue is going to be jet fuels from the Middle East (eg the Qatar Shell/Pearl Gas To Liquids GTL project). The fuels are of extremely high quality but because Sulphur has to be removed from the gas (because it poisons the catalyst used to convert to a liquid) the resultant fuel is very low in Sulphur. Seals corrosivity/swelling/shrinking is also an issue.
None of the above issues are insurmountable with the use of additive packages.
Yusuf Danet hits on an important point - whatever ends up being used it will have to be a "drop-in" replacement. The problem is going to be not that the fuel meets a particular standard but that the compatibility issues between fuels derived from different biomass sources are fungible. While this happens to some extent with conventional fuels (refined from very different crudes around the world) the resulting hydrocarbon fuel is remarkably consistent and compatible. This is not the case at all with biofuels and the immaturity of the industry and the lack of understanding of compatibility issues is a huge concern. There are echoes of BA 038 in this whole debate: we thought we knew conventional Jet inside out - turns out that we don't at all.
For aircraft paraffins I suspect that the limiting factor will be lubricity - and that is related to the very low levels of Sulphur in Biofuels. There have already been fleet fuel pump failure incidents (NZ comes to mind) when severly hydrotreated conventional kero caused failures in the domestic fleet (but not the longhaul fleet which of course fills up all over the world).
Another big issue is going to be jet fuels from the Middle East (eg the Qatar Shell/Pearl Gas To Liquids GTL project). The fuels are of extremely high quality but because Sulphur has to be removed from the gas (because it poisons the catalyst used to convert to a liquid) the resultant fuel is very low in Sulphur. Seals corrosivity/swelling/shrinking is also an issue.
None of the above issues are insurmountable with the use of additive packages.
Yusuf Danet hits on an important point - whatever ends up being used it will have to be a "drop-in" replacement. The problem is going to be not that the fuel meets a particular standard but that the compatibility issues between fuels derived from different biomass sources are fungible. While this happens to some extent with conventional fuels (refined from very different crudes around the world) the resulting hydrocarbon fuel is remarkably consistent and compatible. This is not the case at all with biofuels and the immaturity of the industry and the lack of understanding of compatibility issues is a huge concern. There are echoes of BA 038 in this whole debate: we thought we knew conventional Jet inside out - turns out that we don't at all.
Last edited by Pinkman; 10th Feb 2009 at 09:07.
Join Date: Jan 2008
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Why risk it?
Just wondering what everyone thinks about the first transcontinental jet flight using only BIO FUEL. All comments welcome
From a public perception, if the industry is having problems, after 50 years experience of using existing fuels then stop mucking about with adding another "unknown" to the situation.
Yes chuck it in your car but keep it out of the sky ?
