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Generating Alcohol Fuels From Electrical Current and CO2

Posted by Soulskill on from the we-have-those-things dept.

New submitter AcMNPV writes "A news release from UCLA describes a new process for producing biofuels using microorganisms, electrical current and carbon dioxide (abstract). Quoting: 'Liao and his team genetically engineered a lithoautotrophic microorganism known as Ralstonia eutropha H16 to produce isobutanol and 3-methyl-1-butanol in an electro-bioreactor using carbon dioxide as the sole carbon source and electricity as the sole energy input. Photosynthesis is the process of converting light energy to chemical energy and storing it in the bonds of sugar. There are two parts to photosynthesis — a light reaction and a dark reaction. The light reaction converts light energy to chemical energy and must take place in the light. The dark reaction, which converts CO2 to sugar, doesn't directly need light to occur. "We've been able to separate the light reaction from the dark reaction and instead of using biological photosynthesis, we are using solar panels to convert the sunlight to electrical energy, then to a chemical intermediate, and using that to power carbon dioxide fixation to produce the fuel," Liao said.'"

5 of 82 comments (clear)

  1. Now this could be potentially game changing.... by Ogi_UnixNut · · Score: 5, Interesting

    Butanol is an excellent replacement for petrol, because it can be used in cars with minimal/no modification to the engine (unlike running on ethanol) making it more akin to the petrol equivalent of biodiesel.

    It is also one of the highest density methods of storing energy, and can make use of existing infrastructure (which also doesn't need modification to store, like with ethanol)

    However I clicked a few links down and could not find the paper itself, anyone got a link? The ability to generate butanol without sunlight (and by removing CO2 from the atmosphere) sounds too good to be true quite frankly, as this could potentially solve a lot of problems (without needing to take up huge amounts of land, compete with food production, etc...).

    TFA mentions using solar panels, but the thing is that it uses electricity, you could just as easily generate it from Nuclear, Hydro or any other power source. The potential in future of people being able to generate their own fuel if they so desire could really be a game changer IMO.

    1. Re:Now this could be potentially game changing.... by Solandri · · Score: 5, Interesting

      To put it in perspective, gasoline contains about 34 MJ per liter (129 MJ per gallon). Even if you assume an internal combustion engine vehicle has an abysmal 15% efficiency (fuel to wheels), its usable energy density is 5.1 MJ/l (19.3 MJ/gal). If you spend 3 minutes at the pump filling up 50 liters (13.2 gal), you're transferring energy at a rate of 1.42 MegaWatts.

      If you then assume the electric vehicle is 100% efficient (socket to wheels), to reach 1.42 MW with the 220 V circuit found in most homes, you'd need 6440 Amps. More than 40x the amperage which feeds into the typical home and enough to melt pretty much any wiring most people commonly deal with. This is the big problem with the idea of capacitors as batteries - unless you switch to extremely high voltages (meaning a steep step-down transformer needs to be on board the car with associated weight and efficiency losses), you're not gonna be able to use a cable in place of a gas pump hose to charge them up in a few minutes. The current will need to be transferred by something much more substantial.

      Or if you like the idea of kinetic batteries (flywheels), 1.42 MW is about the same energy dissipation rate as two 2000 kg vehicles traveling 96 kph (60 mph) colliding and coming to a complete stop within 1 second. If you imagine 180 of such crashes happening in the span of 3 minutes, that's how much usable energy you're pumping into your gas tank every time you fill up.

      Liquid chemical fuels contain a helluva lot of energy; so much that it's going to be very difficult for other technologies to supplant them for transportation. I really think the energy storage medium for vehicles in the future will turn out to be alcohol-based biofuels generated like in TFA.

  2. Re:Basically a battery by JazzHarper · · Score: 5, Informative

    Not really. This is a reverse fuel cell. Liquid fuels have higher energy density than batteries.

    ARPA-E has funded a whole bunch of these electrofuels projects.

    Here's one at Harvard, using a different species of bacteria: http://arpa-e.energy.gov/ProgramsProjects/Electrofuels/EngineeringaBacterialReverseFuelCell.aspx

    And yet another one at Columbia: http://arpa-e.energy.gov/ProgramsProjects/Electrofuels/BiofuelsfromCO2UsingAmmoniaOxidizingBacteria.aspx

  3. Re:Sure like to see some info about efficiency... by NoNonAlphaCharsHere · · Score: 5, Funny

    In general, I'm leery of using bioreactors as a production tool. They're expensive, cranky of maintenance and tend to smell bad.

    -> insert ex-wife joke here <-

  4. This beats war any day by cryfreedomlove · · Score: 5, Interesting

    Our current energy policy subsidizes pumping crude oil from the ground. The subsidy consists of a massive influx of American military forces into the Middle East. Imagine life without that. Before you say it is too expensive, make sure you are comparing the cost of this promising new technology to the current costs of war.