Caltech Reactor a Breakthrough for Sustainable Business


From wind turbines to solar photovoltaic cells, sustainable business ventures have produced a plethora of well-tested methods for converting renewable energy into electricity. Though much remains to be done when it comes to actually replacing coal and other fossil fuel-based electricity with a clean energy grid, there is little doubt that the technology to do so exists. A far greater challenge has been finding a truly renewable and sustainable energy source capable of replacing the petroleum-based liquid fuels used to power motor vehicles and aircraft. But scientists at the California Institute of Technology may finally be closing in on a solution.

According to an article in the peer-reviewed journal Science, experiments spearheaded by Professor Sossina Haile of Caltech have succeeded in combining carbon dioxide and water to produce a liquid fuel. The catalyst that facilitates the reaction is the element cerium, and the extremely high temperatures at which the reaction occurs are created by concentrating solar energy. In other words researchers have found a way to do something vaguely similar to what plants do every day: harness the energy of sunlight to convert carbon and water into a liquid fuel.

If cerium solar reactors were ever used on a large scale, it would be a breakthrough for sustainable liquid fuels. So far biofuels are about the best replacement for gasoline and diesel that sustainable business has been able to find. But biofuels—whether made from corn, sugar cane, or palm oil—come with a host of their own problems and questions attached. If their production involves energy-intensive farming methods or the clearing of large tracts of rainforest, the carbon footprint of biofuels may be equal to or even greater than that of gasoline. Though plant-based fuels may eventually be developed that make a real dent in climate change, it so far seems biofuels are no silver bullet solution to our energy problems.

Haile’s research suggests sustainable business could skip the extra step of growing plants that are then converted into fuel. Converting sunlight straight into fuel would do away with the need for chemical inputs and vast areas of land used to grow biofuel crops. Cars, trucks, and airplanes might someday run on a basically carbon-neutral liquid fuels source which avoids most of the problems that come with biofuels. A method for converting sunlight into liquid fuel instead of electricity would also help solve challenges connected to the intermittency of the sun’s energy, because liquid fuel can be easily stored for times when the sun isn’t shining.

All of this will be just theoretical until cerium solar reactors are actually sold and used on a commercial scale. Before that happens researchers will need to refine their methods and work on making the energy conversion process more efficient. Some venture capitalist will probably need to invest in the project, and commit to provide the money for large scale deployment of the technology. But while sustainable business is probably years away from providing solar-powered fuel stations across the country, the day may be coming when drivers can fill up on a tank of sustainable, solar energy-based fuel.

Article by Nick Engelfried, appearing courtesy Justmeans.

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  1. We haven’t figured out how to produce clean, affordable electricity and your article mis-states that fact. It’s fine to be a cheerleader, but we haven’t had that breakthrough yet. Wind and solar are 4-5X as much as coal/natural gas generated electricity and therefore will not replace them.

  2. As much as I’d like to get excited about this, after reading the Science article abstract I find the cleantechie article misleading. It looks like from CO2 and H20 you get H2 and CO and O2(?).. all gases. This is hardly liquid fuel as I think of liquid fuel. How hot does the reaction need to be? How much energy needs to be supplied to support reaction? The statement, “combining carbon dioxide and water to produce a liquid fuel” is not supported by what I read.

  3. Couldn’t access the Science article, but I suspect this suffers from the same snag as using algae: it will need concentrated CO2. Today that can come from coal-fired power-stations, but that doesn’t make for a zero-carbon economy. Turning the CO2 back into a fuel for transport is just a single recycling. The transport releases the CO2 into the air. The overall result is to slow the addition of CO2 to the main cycle, not to halt it.

  4. There will be a transition from fossil fuels to green however that road passes through a liquid fuel stage which allows vehicals that are designed to run diesel use bio-diesel.The vast majority of vehicles on the road today run on liquid fuels.Strictly,from a logistical perspective this is the path that will be taken in light of these new developments that simply skip a step in the process. I think that it is fantastic that the university has done remarkable job. At the end of the day weather you support wind, solar or bio-fuels ect, we should be thankful that there are leaving behind an energy industry that has gotten us into regional as well as world conflicts and has nearly destroyed the planet earth as we know it. The work that each of you contribute today may very well perserve the planet for generations to come. I thank each and everyone of you for your contributions as I am certain future generations of people all over the world will recognize your for the vexxing issues you confronted and were able to solve with hard work and determination. Thank You!

  5. James Stockdale on

    This is all very interesting, but isn’t water already predicted to replace oil in terms of what wars are waged over? It seems this will only expedite the transition. In the same way that biofuels were quite exciting until we realised that they compete for the vital resource of arable land, won’t this just serve to increase water stress?

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