Sandia National Laboratories  [Printer-friendly version]
December 5, 2007


Albuquerque, N.M. -- Using concentrated solar energy to reverse
combustion, a research team from Sandia National Laboratories is
building a prototype device intended to chemically "reenergize" carbon
dioxide into carbon monoxide using concentrated solar power. The
carbon monoxide could then be used to make hydrogen or serve as a
building block to synthesize a liquid combustible fuel, such as
methanol or even gasoline, diesel and jet fuel.

The prototype device, called the Counter Rotating Ring Receiver
Reactor Recuperator (CR5, for short), will break a carbon-oxygen bond
in the carbon dioxide to form carbon monoxide and oxygen in two
distinct steps. It is a major piece of an approach to converting
carbon dioxide into fuel from sunlight.

The Sandia research team calls this approach "Sunshine to Petrol"
(S2P). "Liquid Solar Fuel" is the end product -- the methanol,
gasoline, or other liquid fuel made from water and the carbon monoxide
produced using solar energy.

Sandia is a National Nuclear Security Administration (NNSA)

CR5 inventor Rich Diver says the original idea for the device was to
break down water into hydrogen and oxygen. The hydrogen could then
fuel a potential hydrogen economy.

The Sandia researchers came up with the idea to use the CR5 to break
down carbon dioxide, just as it would water. Over the past year they
have shown proof of concept and are completing a prototype device that
will use concentrated solar energy to reenergize carbon dioxide or
water, the products of combustion. This will form carbon monoxide,
hydrogen, and oxygen, which ultimately could be used to synthesize
liquid fuels in an integrated S2P system.

Coresearchers on the project are Jim E. Miller and Nathan Siegel.
Project champion is Ellen B. Stechel, manager of Sandia's Fuels and
Energy Transitions Department.

Stechel says that researchers have known for a long time that
theoretically it might be possible to recycle carbon dioxide, but many
thought it could not be made practical, either technically or

"Hence, it has not been pursued with much vigor," she says. "Not only
did we think it was possible, the team has developed a prototype that
they fully anticipate will successfully break down carbon dioxide in a
clever and viable two-step process."

Stechel notes that one driver for the invention is the need to reduce
greenhouse gases.

"This invention, though probably a good 15 to 20 years away from being
on the market, holds a real promise of being able to reduce carbon
dioxide emissions while preserving options to keep using fuels we know
and love," she says. "Recycling carbon dioxide into fuels provides an
attractive alternative to burying it."

Providing funding for Sunshine to Petrol is Sandia's internal
Laboratory Directed Research and Development (LDRD) program. The
research has also attracted interest and some funding from DoD/DARPA
(Defense Advanced Research Projects Agency).

"What's exciting about this invention is that it will result in fossil
fuels being used at least twice, meaning less carbon dioxide being put
into the atmosphere and a reduction of the rate that fossil fuels are
pulled out of the ground," Diver says.

As an example, he says, coal would be burned at a clean coal power
plant. The carbon dioxide from the burning of the coal would be
captured and reduced to carbon monoxide in the CR5. The carbon
monoxide would then be the starting point of making gasoline, jet
fuel, methanol, or almost any type of liquid fuel.

The prospect of a liquid fuel is significant because it fits in with
the current gasoline and oil infrastructure. After the synthesized
fuel is made from the carbon monoxide, it could be transported through
a pipeline or put in a truck and hauled to a gas station, just like
gasoline refined from petroleum is now. Plus it would work in ordinary
gasoline and diesel engine vehicles.

Miller says that while the first step would be to capture the carbon
dioxide from sources where it is concentrated -- e.g., power plants,
smokestacks, and breweries -- the ultimate goal would be to snatch it
out of the air. A S2P system that includes atmospheric carbon dioxide
capture could produce carbon-neutral liquid fuels.

"Our overall objective with this prototype is to demonstrate the
practicality of the CR5 concept and to determine how test results from
small-scale testing can be expanded to work in real devices," Miller
says. "The design is conservative compared to what might eventually be

Diver says the prototype should be completed by early next year. He
hand-built the precision device in a shop at Sandia's National Solar
Thermal Test Facility and is now waiting on a few parts to finalize
it. Initial tests will break down water into hydrogen and oxygen. That
will be followed by tests that similarly break down carbon dioxide to
carbon monoxide and oxygen.

Besides having a nearly completed prototype, the research team has
already proven that the chemistry works repeatedly through multiple
cycles without losing performance and on a short enough cycle time for
a practical device.

"We just now have to do it all in one continuous working device,"
Siegel says.


Sandia is a multiprogram laboratory operated by Sandia Corporation, a
Lockheed Martin company, for the U.S. Department of Energy's National
Nuclear Security Administration. With main facilities in Albuquerque,
N.M., and Livermore, Calif., Sandia has major R&D responsibilities in
national security, energy and environmental technologies, and economic

Sandia news media contact: Chris Burroughs,, (505)

Copyright 2007 Sandia Corporation