Environment

Researchers generate liquid fuel using electricity

Researchers generate liquid fuel using electricity
UCLA researchers have generated isobutanol from CO2 using a genetically engineered microorganism with solar electricity the sole energy input
UCLA researchers have generated isobutanol from CO2 using a genetically engineered microorganism with solar electricity the sole energy input
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UCLA researchers have generated isobutanol from CO2 using a genetically engineered microorganism with solar electricity the sole energy input
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UCLA researchers have generated isobutanol from CO2 using a genetically engineered microorganism with solar electricity the sole energy input

While electric vehicles have come a long way in the past decade, they still have many disadvantages when compared to internal combustion engine-driven vehicles. The lithium-ion batteries that power electric vehicles have a much lower energy storage density when compared to liquid fuel, they take longer to “refuel,” and they lack the supporting infrastructure that has built up around conventional vehicles over the past century. Now researchers at the UCLA Henry Samueli School of Engineering and Applied Science have developed a process that could allow liquid fuel to be produced using solar generated electricity.

Using only electricity for the energy input, the team was able to convert carbon dioxide into the liquid fuel isobutanol. They did this by genetically engineering a lithoautotrophic microorganism (one that utilizes inorganic compounds as energy sources) known as Ralstonia eutropha H16 to produce 3-methyl-1-butanol and isobutanol, a colorless, flammable liquid that holds potential as an alternative to gasoline in combustion engines. The microorganism was placed in an electro-bioreactor and used only carbon dioxide as the carbon source and electricity as the sole energy input.

The team says storing electrical energy as chemical energy in higher alcohols in this way would allow it to be used as liquid transportation fuels.

"The current way to store electricity is with lithium ion batteries, in which the density is low, but when you store it in liquid fuel, the density could actually be very high," said James Liao, UCLA's Ralph M. Parsons Foundation Chair in Chemical Engineering. "In addition, we have the potential to use electricity as transportation fuel without needing to change current infrastructure."

The process developed by the UCLA team carries on from previous success in producing isobutanol by genetically modifying a cyanobacterium to consume carbon dioxide. Like that previous work, this new method also mimics photosynthesis, but with an important difference. Photosynthesis has two parts – a light reaction, which converts light energy to chemical energy, and a dark reaction, which converts CO2 to sugar and 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. "This method could be more efficient than the biological system."

While the CO2 conversion process in the lithoautotrophic microorganisms could theoretically be driven by hydrogen generated by solar power, the team chose formic acid as a substitute energy carrier due to the low solubility, low mass-transfer rate and the safety issues surrounding hydrogen.

"Instead of using hydrogen, we use formic acid as the intermediary," Liao said. "We use electricity to generate formic acid and then use the formic acid to power the CO2 fixation in bacteria in the dark to produce isobutanol and higher alcohols."

The researchers say the method they have developed also has the potential to allow the bioconversion of CO2 to a variety of chemicals. Additionally, Liao says the transformation of formate into liquid fuel will also play an important role in the biomass refinery process. Now that they’ve proven the process works, they are looking to scale it up.

The team’s study is published in the journal Science.

Source: UCLA

8 comments
8 comments
Robert Knapman
With all the hype over greenhouse gases and the oilsands CO2 storage, this sounds like a bonafide idea. Now, can we get it past congress.....
Facebook User
Well Robert- not while the US dollar is propped up by oil, the bank and oil lobby will kill it dead - unless it is used by the US marines in Afghanistan who can use the military industial complex to force technological changes like this into the mainstream. Nothing quite like reducing the number of fuel supply trucks being blown up by the taliban and saving American lives(introduced solar power in the supply chain). In the challenger disaster Mcdonald of thircol lobbied everyone but the right people to stop the doomed launch. A phonecall to the President or to Mr Armstrong would have meant the crew would have refused to board.
You have to talk to the right people who really have a fuel supply problem, or consider this a life or death issue.
Dave Andrews
Screw congress. Just do it!
Jim Parker
If you think of technology development like minor league baseball, this tech is in the developmental league. It's got to work through several more levels before it's ready for the show.
Slowburn
It looks like a better system than the electrically driven water to hydrogen + co2 to methane to liquid fuel system but only if it uses less electricity.
I would love to see either system produce the aircraft fuel on a nuclear aircraft carrier.
Slowburn
re; David Kendrick
The dollar is not propped up by oil in fact the opposite. The dollar is propped up by a strong economy and nuclear weapons.
Bruce Curtis
First, a CO2 source has to be found; atmospheric concentrations are measured in parts per million, far too small to be extracted economically. that leaves fuel-burning power plants and fixed livestock operations. Maybe outside the US...here, confiscatory tax policy and intrusive 'environmental' and business regulations make creative new energy impractical, given the current political climate.
NatalieEGH
1. Might not a possible method for making this more commercially feasible be down scaling to say private residence sized systems.
The recent reaction to Tiger Direct's April Fools Joke indicates there is an intense desire by tens if not hundreds of thousands of individuals to centralize energy production. From what I understand over 20,000 people called Tiger Direct seeking the ability to purchase the item listed before it was published all over the internet the advertisement was just an April Fools Joke and calls finally stopped. Had the technology really existed, I have no doubt that within 5 years, the utility companies would have devolved into only backup systems, charging a monthly fee to maintain infrastructure and for standby emergency service.
2. As to carbon dioxide concentrations in the atmosphere, it is true carbon dioxide makes up only .039445% of the atmosphere compared to nitrogen 78.084% and oxygen at 20.946%. However a semipermeable membrane that only allows the passage of carbon dioxide may make the system more efficient. This would result in the creation of a negative pressure inside the system that could only be equalized by the transport across the membrane of CO2. Such membranes are commonly used in physics, biology, and medical research and applications. They have been created to isolate many different types of molecules including CO2.