Scientists from Sandia National Labs have successfully field-tested a machine that uses solar energy to convert CO2 waste from power plants into fuels such as gasoline, diesel, and jet fuel.
Cylindrical in shape, the device has both a hot and cold chamber with 14 Frisbee-like rings in the middle. The rings’ outer edges–made of iron oxide–are solar heated to 2,700 degrees which forces the composite to lose oxygen atoms.
As the rings rotate (one revolution a minute), they move in towards the cool chamber. There, carbon dioxide is added and the iron oxide composite takes back its missing oxygen atoms. The resulting carbon monoxide would be used in creating a synthesized liquid combustible fuel.
Invented by Rich Diver, we first discussed the device in January of last year. Until recently, it had only been tested in a laboratory. But a fully hand-built, and much larger, version was just successfully tested. “This is a first-of-its-kind prototype we’re evaluating,” Diver explains.
The device is called the Counter-Rotating-Ring Receiver Reactor Recuperator or the CR5 for short. I think we’ll stick to that shorter title for now. This method of forced-photosynthesis was initially designed for creating cheap abundant hydrogen fuel.
“In the short term we see this as an alternative to sequestration,” SNL Advanced Materials Laboratory chemical engineer James Miller, who has also been part of the research, adds.
This type of CO2 recycling could take trapped carbon waste from power plants and then returned for production, instead of releasing it to the air. Though, the resulting syngas does just burn right back into CO2–not exactly ideal.
Regardless, we’re looking at 15-20 years before the tech is market ready. Researcher’s hope to achieve an efficiency of a few percent which is about double that of real-world photosynthesis.
“Ultimately, we believe we have to get in the range of 10% sunlight-to-fuels, and we’re a long way from doing that,” said Miller.
A few places we could use this tech now, the biggest CO2 polluting power plants in the U.S. (annually):
- The Scherer plant in Juliet, GA — 25.3 million tons
- The Miller plant in Quinton, AL — 20.6 million tons
- The Bowen plant in Cartersville, GA — 20.5 million tons
- The Gibson plant in Owensville, IN — 20.4 million tons
- The W.A. Parish plant in Thompsons, TX — 20 million tons
“People have known for a long time that theoretically it should be possible to recycle carbon dioxide, but most still think it cannot be made practical, either technically or economically,” says Ellen Stechel, the program manager for the Sandia team.
A liquid hydrocarbon fuel is significant as it fits our current gasoline and oil infrastructure. It can be easily transported via the pipeline or hauled to a gas station. And, it would work in ordinary petro-based engines.
Source: Popular Science