I just saw on a Dutch TV programme ; Noorderlicht (http://noorderlicht.vpro.nl/) (meaning aurora borealis) that a yet unpublished and unreported discovery has been made where genetically changed bacteria made alcohol out of light and CO2. As you know, alcohol can be used as a fuel.

Taking into account that this news might be a hoax, or an incomplete science project or for whatever reason not true - If this happens to be true; do you think filling your tank with bacteria and basically driving on thin air be realistically possible ?

Probably not. Cars need a lot of power, more then they can get via solar radiation (which is why solar cars impractical), plus solar energy is unreliable.

It might be a good componant of an alcohol based fuel system, but it would probably needed to be implemented in larger structures.

So they actually strung together some CO2 into a chain, and then some H20 tacked on for an alcohol?

Interesting. Especially as this would be a potential carbon sink as well. Question, how efficient is it?

I'd put my bet on good old electric cars: nuclear power plants and other stuff show more promise to me than trying to find a replacement equivelant in use to gasoline. Technologies already there (or close enough) to power a common car for 150+ miles on electric charge, and it would be much easier converting the economy to that as opposed to redesigning infrastructure for hydrogen cells or another fuel. As for bacteria, I'll listen to perfy.

Wow, that would be great if it turns out to be true. And additionally, alcohol can not only be used as fuel for cars :D - get drunk and safe the world!

For those able to understand Dutch -> play this URL in your media player mms://cachemedia.omroep.nl/rambo01/0/id/VPRO/serie/AUTO_NOORDERLICHTNIEUWS/VPRO_1125159/bb.20080227.asf

Item starts at 10:34 and lasts till about 14:00.

do you think filling your tank with bacteria and basically driving on thin air be realistically possible ?
No.

Is this ethanol or methanol? I would actually expect that its more likely to be methanol.

Anyway - the problem with this would be that it still requires energy. There will have to be more energy put-in via light to the bacteria than will be stored in the alcohol.

Secondly, I'd imagine that a rich source of CO2 would be required to make this remotely efficient. For example, extracting enough CO2 form "thin air" to produce 1 kg of methanol would require nearly 2500 m³ of air (assuming the CO2 in the air was at 300 ppm).

There is then the problem of purifying the alcohol so that it will burn - which again requires energy to remove the water etc.

In summary - it may be viable in a large industrial scale, but certainly not in a car!

And in factories like we now have oil-refineries ?

CO2+light-->CH3OH

That doesn't add up. No hydrogen on the left side of the equation. And as stated above, the energy in sunlight, ~1kW/square meter, is not enough to power a car, even at 100% efficiency, which nothing can be.

And essentially, that's all such an idea could be, a way to convert sunlight to another form of energy. For any sizeable output, that means huge areas of solar collectors. Wherther you store the energy in hot water, electricity, or alcohol, the energy has to come from somewhere, in this case, sunlight.

Dubai,

Consider that as bacteria, they are almost guaranteed to require an aqueous environment, and therefore water and hydrogen ions.

Apparently some phototrophic (green) bacteria are able to fix carbon, but the caveat of course is they have to be exposed to the sun. So for instance your car would need a sun 'pond', and like Ainwood said, the metabolic waste would have to be purely alcohol fuel, or else filtered/purified before it entered the fuel line of the car. Amusing if CO2 from fuel combustion, and the driver's breath would fuel the bacteria.

Well, they can make car batteries out of bacteria, so there you go.

I'd stick with electric cars, biofuels simply don't cut it for it still will use gasoline. If we could make a 100% natural fuel, then we can talk. ;)

Apparently some phototrophic (green) bacteria are able to fix carbon, but the caveat of course is they have to be exposed to the sun.
Indeed. It's a very promising technology too:

The process could use a photosynthetic bioreactor supplied with exhaust gasses from a fossil fuel combustion source to grow algae. As smokestack emissions are delivered to the algae bioreactor, carbon dioxide and other pollutants are absorbed and utilized by the algae to grow at an exponential rate. Once harvested, the algae is processed to produce a variety of solids such as protein and bioplastics, gasses such as methane, and biofuels such as ethanol and bioDiesel. (...) The biofuel yield using the GreenFuel technique is 30 times higher per hectare compared to the yield of oil derived from conventional terrestrial crops.
Source (http://en.wikipedia.org/wiki/GreenFuel_Technologies_Corporation)

IMO this seems to be a very promising approach. Storing CO2 from power plants is in many cases difficult/impossible, depending on the location etc. If you can use this CO2 to grow algae which in turn produce fuel, it's as if we get fuel "for free" -- one tonne of oil gives X kWh of energy in the powerplant AND Y litres of biofuel in addition. Sure, the CO2 is lost into the atmosphere in the end, but the energy-pr-unit-CO2-released improves drastically.

That is, of course, if they manage to get it working correctly. I read an article in Time magazine before Christmas which discussed this and other sources of biofuels. Apparently they have some problems in going big-scale with this, but hopefully that can be overcome. I'm a technology optimist. :)

As for the "fuel of the future": I have three things to say:


Biofuels might be part of the solution (see above).
The bigger the combustion engine, the easier it is to filter out CO2. Therefore small mobile engines, such as in cars, will be very hard to filter. I believe that no matter what happens, we will use up all our natural gas/oil resources. Maybe it would be best to use these resources for powering those mobile units (cars etc), where they will be needed for the longest, and focus on filtering- and storage technology as well as new energy sources (fusion etc) for the big power plants?
Personally I believe that we'll see a revolution in battery technology within a few years. I'm studying nanotech myself, and the possible applications of nano in this field are vast. If in 10 years we'll have batteries that weigh 1 kilogramme that can hold enough energy for you to drive your car from Miami to Seattle, wouldn't that be great? If this "battery revolution" comes, we can eliminate all mobile combustion engines, which are the ones that are most difficult to cleanse (as pointed out above). Then we can have a few centralized power plants that supply power to whole regions.

I think bacteria in a gas tank would not be sufficient for the car demands quite a lot of fuel.

But if that bacteria-thing really exist, then it might be good news.

As Dubai Vol alluded to, energy doesn't come for free. Completely aside from the logistics of getting enough CO2 to manufacture a reasonable amount of fuel, you need energy to turn it into fuel, and the amount of energy required is always more than ends-up in the fuel in the first place.

Ie - conversion of CO2 into methanol via bacteria is more analogous to a battery than to (say) oil. It is converting energy in the form of sunlight into stored energy (the methanol) - it does not create energy.

Of course it doesn't create energy. But it makes the sun's energy available to us without the use of solar cells or other energy-intensive techniques. It's like a greenhouse for algae.

Essentially, exhaust gas from the power plant is bubbled through cylindrical upright tanks full of algae-laden water. The algae extract the CO2 from the exhaust and convert it to sugars via photosynthesis. Via further metabolism these sugars are then converted to oils and proteins.

Portions of the algal soup are continually removed and dried into algae cakes. The cakes are then repeatedly washed with solvents to extract the ‘algal oil’. This oil is then converted to biodiesel via transesterification and the remaining biomass is treated with enzymes, thereby converting starches into simple sugars. Ethanol can then be produced via the fermentation of these simple sugars.
Source. (http://www.ecosherpa.com/news/algae-co2-biofuel/)

For those who have access to New Scientist online, here (http://technology.newscientist.com/channel/tech/mg19225725.600-biofuel-made-from-power-plant-cosub2sub.html) is the full article.

Absorbing 40% of the CO2 (which seems to be where the technique is most effective) from a 1000 MWh powerplant would require 8-16 square kilometers. That would yield as much biofuels as you'd get from growing rapeseed on a area 33 times that size. Some algae have an oil content of 75% their dry weight.

A big 1 square kilometer test facility will open in 2009. Hopefully we'll get more answers then. I'm not saying there won't be problems -- I'm just saying that it looks very promising and something that should definitely be looked into. With soaring grain- and corn prices the incentive for further research should definitely be in place.

What if we run out of C02?

Ainwood: It doesn't matter if the energy required to turn CO2 via algae and bacteria into an alcohol is more than alcohol gives while burning it if the energy used is unused otherwise. As The Fionis points out; sunlight will be the source of energy to turn CO2 into an alcohol.

I agree that this process doesn't create energy. And I'm glad I have never claimed that. That would be a violation of the 1st law of Thermodynamics.

Al_da_Great: CO2 is re-formed by burning Alohol.
Or: C2H6O + 3 O2 -> 2 CO2 + 3 H2O

At the very least this must require water in addition to CO2 and light, as a hydrogen source, and if the bacteria can't get that from atmospheric water vapour (which is very unlikely), you'll therefore need to keep filling a water tank.

This is never going to work on such a small scale as a car. For starters you've got to expose all this bacteria to sunlight and air, which is going to be rather tricky. The surface area of a car isn't that large, and you'd need a colossal amount of bacteria to produce a significant amount of fuel.In any case, surely solar panels are more efficient than this approach, and perform the same overall conversion of sunlight to motion.

It might be some use on a much larger scale - alcohol is a better energy store than batteries. A way of getting biofuels which didn't require vast amounts of vegetable matter would actually make them worth considering.

This already is possible sorta but not quite....beer, and wine. Yeast eat sugar and give off alcohol.

However to go from single carbon to multi carbon molecules would require more energy. The bacteria would have a net loss of energy from the process since you arent breaking many carbons down to lower carbon strands but instead making carbon carbon bonds. While the process would be like photosynthesis, it would not produce a molecule that the bacteria could use.

Co2 + water results in O2 waste, sugar for plant use. This process would be CO2 plus water and alcohol waste...wheres the benefit for the bacteria. Nothing stays behind.

Ainwood: It doesn't matter if the energy required to turn CO2 via algae and bacteria into an alcohol is more than alcohol gives while burning it if the energy used is unused otherwise.

Point was it would not be viable to put CO2 in your car, and have the bacteria create energy with it.

Because the process would likely create methanol in water you would then need to distill the methanol out, which is quite an energy intensive process.

In summary - I agree that it is a possible means of using sunlight to create stored energy, but I think there are more efficient means.

I think the other big concern is, how will developing biofuels that use grains effect the world grain prices. By pushing them up we will cause increasing famines and growing numbers of people who can't afford food. It seems like a high cost so we can drive our cute cars.

I think algae looks like the best options as it at least isn't a food that people normaly use, and it uses less space.

That would yield as much biofuels as you'd get from growing rapeseed on a area 33 times that size. This is what's interesting in this matter. It would be an amazing breakthrough if it succeeds. Perhaps it would even be viable to produce electricity this way?

I think the other big concern is, how will developing biofuels that use grains effect the world grain prices. By pushing them up we will cause increasing famines and growing numbers of people who can't afford food. It seems like a high cost so we can drive our cute cars.
Not only do they drive food prices up but they destroy the Amazon rainforest and worsen GW

The problem with this process is the water consumption. Supposing methanol is formed, we would have to realize that the reaction would require 2 moles of water for every one mole of methanol. Unless we fix our water shortage problems, we need to stick to refining our battery systems.

Edit: Complete mental lapse. 2 moles of water.

The problem with this process is the water consumption. Supposing methanol is formed, we would have to realize that the reaction would require 4 moles of water for every one mole of methanol. Unless we fix our water shortage problems, we need to stick to refining our battery systems.
H2O mole = 18 grams
H3COH mole = 32 grams

4H2O -> 8H 4O
2CO2 -> 2C 4O

8H 8O 2C -> 2H3COH + 3O2

My calculations give just 36 grams of water to 32 grams of methanol

I agree that some sort of biological photocell like algae is a very logical choice---it's a natural solar panel.

Corn is a really bad choice since it's expensive to produce regardless. I wouldn't completely rule out crop plants being used to generate fuel, but I seriously doubt it will be corn, or any plant that is a major food staple. Most likely we will see research on food staples for biofuel purposes quickly diverted to other areas in the near future, and the arguement that "biofuel = starving the poor" will quickly become a strawman arguement.

I think the other big concern is, how will developing biofuels that use grains effect the world grain prices. By pushing them up we will cause increasing famines and growing numbers of people who can't afford food. It seems like a high cost so we can drive our cute cars.

I think algae looks like the best options as it at least isn't a food that people normaly use, and it uses less space.

H2O mole = 18 grams
H3COH mole = 32 grams

4H2O -> 8H 4O
2CO2 -> 2C 4O

8H 8O 2C -> 2H3COH + 3O2

My calculations give just 36 grams of water to 32 grams of methanol

Sorry, I meant a two to one molar ratio. But still, think of the water reacted to produce said fuel. We are already beginning to strain water resources.

Sorry, I meant a two to one molar ratio. But still, think of the water reacted to produce said fuel. We are already beginning to strain water resources.
If it works on salt water there's not a single problem. If not, even then the water will become water again when the methanol burns, which eventually will return to the water sources. Not that it couldn't make problems before it goes back.

But do the bacteria thrive in a saline solution?

Well, all freshwater resources aren't strained only certain ones. We don't have a worldwide freshwater shortage or anything.

But do the bacteria thrive in a saline solution?
That is the problem, as I guess no. As Perfy said, there are places with ample freshwater but if all sources are utilised there's going to be a problem.

I couldn't open the link so I didn't see the program but there are micro-organisms that already produce alcohol (like yeast, obviously) so I expect they genetically modified those or at least used there genes. Also, most micro-organisms produce ethanol (CH3CH2OH) So I expect thats the alcohol they produce.

Off Topic: Hey Rik, we live in the same city :p

It'll be batteries that save us, it's not optimal now but they'll only get better and cheaper...
btw batteries actually have better energy density than compressed hydrogen gas.

nuclear fusion of H -> He yields about ~7% efficency, maybe one day we can make the process stable.

Batteries are already pretty good!

http://www.gizmag.com/britains-lightning-gt-electric-supercar/9059/

250-mile range, ten minutes for full charge, sounds pretty awesome, oh yeah, and the car does 0-60mph in 4 seconds.

I think the other big concern is, how will developing biofuels that use grains effect the world grain prices. By pushing them up we will cause increasing famines and growing numbers of people who can't afford food. It seems like a high cost so we can drive our cute cars.

I think algae looks like the best options as it at least isn't a food that people normaly use, and it uses less space.


Not only do they drive food prices up but they destroy the Amazon rainforest and worsen GW

Biofuels affecting food prices?

LIES. And they don't destroy the Amazon Rainforest. Please, I live in Brazil. In a area of Amazonic Region. Get yer nonsense outta here, please.

Biofuels affecting food prices?

LIES. And they don't destroy the Amazon Rainforest. Please, I live in Brazil. In a area of Amazonic Region. Get yer nonsense outta here, please.

Well as Brazilian ethanol is made out of sugar whatsits (socker rör in Swedish) and not grains they do not compete with food production other than using agricultural land for fuel in stead of food, but still Brazil could never produce enough ethanole for the whole world.

The main problem with Brazilian ethanol is ethical, that the sugar barons steal land from poor peasants and that the plantation workers work under wery bad conditions, and people who protest get murdered.