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First Flight of Jet Powered By Algae-Fuel
s31523 writes "Today a US airline carrier conducted a 90 minute test flight with one of its engines powered by a 50/50 blend of biofuel and normal aircraft fuel. This was the first flight by a US carrier after other airlines have reported trying similar flights. In February 2008, a Virgin 747 flew from London to Amsterdam partly using a fuel derived from a blend of Brazilian babassu nuts and coconuts. At the end of December, one engine of an Air New Zealand 747 was powered by a 50/50 blend of jatropha plant oil and standard A1 jet fuel."
Bio-fuel from algae is going to be an interesting field. It's easy to grow, difficult to harvest, and takes a lot of it to make into fuel. But it doesn't take up valuable cropland like corn does and really can be grown anywhere you're willing to build tanks. Solix (http://www.solixbiofuels.com/) is one such company working on the issue who see the potential of building tanks by power plants and then using the CO2 emissions to feed the algae.
Due to the low Energy Return on Energy Invested inherent to biofuels, you can't really make the stuff too far from its point of use, as the transport of the material would exceed its energy value. Jet aircraft are insanely inefficient and guzzle fuel at prodigious rates, and require fuel that has a high energy density. As a consequence I do not see biofuel for jets as anything but a stop gap measure.
I suggest you move to where you like to live, so you can plan out your future, because in a few short decades, you're not going anywhere cheaply or quickly.
RS
Shoes for Industry. Shoes for the Dead.
It is well known that biofuels can (at a cost) be refined to meet most specifications. Providing there is some mineral fuel in the blend to prevent microbial contamination and growth, using this should cause no problems apart from cost. But since jet kerosene is generally untaxed, it is harder to subsidise biofuel replacements than it is for road fuels.
This would not be pursued to the extent that it has been if those questions have been laid to rest already. Most chemists and chemical engineers out there are familiar with ecology nowadays and performing such Life Cycle Analysis is routine.
For an actual example, see for instance "Environmental, economic and energetic costs and benefits of biodiesel and ethanol biofuels", Hill et al, PNAS, vol 103, no 30, 11206-11210.
The net energy gain (over the energy costs of production) is about 25% for corn ethanol, almost 100% for soybean biodiesel (probably higher for algae) and promises to be upwards of 300% for cellulosic ethanol.
Algae and cellulosic ethanol do not displace food crops. Land (and forest) do not sequester carbon to any significant extent - the decomposition process of dead plant matter releases the carbon back into the atmosphere.
In many ways liquid hydrogen would be an ideal aviation fuel. It is clean, has a high energy/weight ratio, it has already been demonstrated ( The Russians developed a Hydrogen passenger Jet during the first Oil crisis ), it scales and because airlines have much more predictable traffic patterns than does your home car, you don't need to store it for days or weeks, meaning the cooling and insulation systems can be much simpler.
The catch is the cost of producing hydrogen in an environmentally friendly manner. Renewable and nuclear energy sources can produce it from electrolysis of water, but even the most advanced and experimental schemes only achieve an efficiency of about 50% using already expensive electricity, and that does not include the energy needed to compress and liquefy it.
They grow it in huge tanks that take up very little space compared to the mass they produce. It's actually one of the most viable sources of biomass that they have come up with yet, and the waste after extracting the oils can be used as fertilizer. So Algae is a win win bio fuel.
Why bother
>> Land (and forest) do not sequester carbon to any significant extent - the decomposition process of dead plant matter releases the carbon back into the atmosphere.
Actually, they do - however to a finite capacity. It's true that as plants die, the carbon goes back into the environment, but new plants grow to replace them. Once you deforest an area, or cut it down to grow crops, you've permanently released that carbon to the atmosphere - You're taking an existing carbon sink and destroying it.
If you compare that to farmland, it's not the same effect. You start with bare land, grow crops, then burn the results - net neutral except for the energy put into growing the crops (unless you chopped down a forest to create the farm land in the first place).
I agree that more advanced crops that are easier to convert to fuel are the answer, especially if we're not displacing existing carbon sinks to grow these. The fact that most ethanol comes from low-yield sources like corn today, competing with food crops, is worrying.
MC
I used to have a sig, but I set it free and it never came back.
Weight is at a premium in an airplane and batteries are quite heavy compared to the energy they have stored.
It's even worse than that. Even if a battery had the same energy density (by weight) as fuel, it would still be worse because the batteries do not get lighter over the course of the flight, so the aircraft must constantly expend energy to carry that mass. By burning fuel you lighten your load over the course of the flight which makes flying progressively cheaper.
Also, many aircraft can't (safely) land with a full tank of fuel. They are designed such that the landing weight will be lower (due to burning fuel) than the takeoff weight. This is why planes making emergency landings sometimes need to dump fuel.
Sewage. Sewerage is what sewage flows through.
Jets typically run on a naptha/kerosene blend
Only in very cold climates where the naptha keeps it from getting gooey. That stuff, called Jet-B, is widely banned elsewhere because it will ignite too easily in a crash landing. The rest of the civil aviation world uses Jet-A (in the USA) and Jet-A1 (elsewhere). Apart from having the solid crap filtered out of it, and some microorganism and corrosion inhibitors added, it's plain old kerosene -- your grandfather's coal oil.
rj
Look up Solix for a company that is investigating this. Algae are really the only long-term viable source of bio-diesel.
Those who can, do. Those who can't, sue.
Actually, I started out at -1. My karma was Terrible. This is apparently what happens if you have a couple of +5 Funny comments. Now, thanks to this Informative post, my karma went up to Bad.
/. karma system that has yet to make sense to me. I just have those moderators who actually read -1 comments to thank.
So there are no morons who modded me down, only a
Nice trolling.
If you have ever been to countries such as Japan, Germany or France, you would have been able to see that fast rail is a very good thing. Just because it has been extremely poorly implemented in the United States does not mean it can't be done well.
To note:
1. airplanes can afford a single failure just as much as train. In fact, the design standards are about equal although typically the trains have higher requirements for safety. (I am a reliability and safety engineer)
2. Trains exist already that can go upward of 300 km/h- look at TGV, ICE, Thalys or upward of 400 km/h - see maglev trains. The limiting factor for rail based trains is mainly the electric powerlines. The french speed record was achieved only by extra tension in the cables. Therefore the maglev trains have higher potential where there limits are only air resistance. These trains are more 21st century than todays civil airliner designs that are a basic WWII design with improved engines.
3. Trains are not as easy to attack as you think. High speed trains pretty reinforced rails, usually are fenced in like airports and if you mess about the tracks to much, you won't be around for too long.
4. Horses for courses. Within a landmass, trains can be much faster than planes as you don't have to deal with traffic and circulation patterns, weather, security control, getting out of the city to the aiport, getting suitcases, etc.
So please get realistic and get to know the technology first before you knock it
The most productive source of bio oil is hemp, which has many non THC strains, but is illegal anyway.
Too bad the US gov is morons... Of course flying a hemp powered plane might not inspire confidence.
-Viz
Don't kid yourself. It's the size of the regexp AND how you use it that counts.
What you say isn't entirely true from what I have read.
The Algae is usually seperated from the water through filtration or skimming of some sort and then pressed to extract the oil. The waste product can then be dried out and broken up to be used as food stuff for the algae that you still have growing. So while the algae isn't generating as much waste as the other options it's not 100% production either.
The big difficulties I seem to remember were in getting useful amounts of oil out of the strains of algae they could easily grow. While there are millions of different strains of algae there are only maybe a couple hundred that can produce enough oil to be worthwhile. They need to find a hardy strain of algae that won't easily be displaced by an invading strain that doesn't produce enough fuel. And at the same time that won't wipe out all other algae strains in the area.
Yes, I know, I work on them for a living :) I wouldn't exactly call them "simpler", though. The basic concept is simple enough, but large jet-turbine engines are anything but simple.
And yes, the fuel is considerably cheaper. There's no point spending extra money in processing the fuel when your engines can handle a high level of impurity. Basic economics.