Carbon Dioxide Conversion to Ethanol

Default ARPA-E Project Image

Berkeley, California
Project Term:
06/16/2017 - 10/31/2018

Technology Description:

Opus 12 will develop a cost effective, modular reactor to electrochemically convert CO2 to ethanol in one step using water, air, and renewable electricity. Electrochemical reduction of CO2 has been demonstrated in laboratories to produce different fuels and chemicals, but these technologies do not provide efficient conversions and can only be executed in non-economical reactors. The Opus 12 team will integrate its novel cathode layer formulation, containing CO2 reducing catalysts and a polymer electrolyte, into an existing proton exchange membrane (PEM) electrolyzer architecture. Their unique polymer-electrolyte blend used in the cathode catalyst layer acts to minimize competing reactions by controlling the pH at the active sites. Currently, PEM electrolyzers are limited to hydrogen production, but the team's approach expands their use to include high-efficiency ethanol synthesis. PEM electrolyzers are also a well-established technology and integrating them into an existing reactor architecture reduces system capital costs and scale-up risk. PEM electrolyzers can also ramp quickly, allowing the use of intermittent, low-cost renewable electricity. They operate at high current density, leading to a small footprint, and they are operationally simple, with no need for specialized operators on site. The team's system will operate at less than 80°C and near atmospheric pressure with a coproduct of pure oxygen. The team's pilot reactor will be one of the first examples of a PEM electrolysis system used to generate a liquid fuel directly.

Potential Impact:

If successful, developments from REFUEL projects will enable energy generated from domestic, renewable resources to increase fuel diversity in the transportation sector in a cost-effective and efficient way.


The U.S. transportation sector is heavily dependent on petroleum for its energy. Increasing the diversity of energy-dense liquid fuels would bolster energy security and help reduce energy imports.


Liquid fuels created using energy from renewable resources are carbon-neutral, helping reduce transportation sector emissions.


Fuel diversity reduces exposure to price volatility. By storing energy in hydrogen-rich liquid fuels instead of pure hydrogen in liquid or gaseous form, transportation costs can be greatly reduced, helping make CNLFs cost-competitive with traditional fuels.


ARPA-E Program Director:
Dr. Grigorii Soloveichik
Project Contact:
Dr. Kendra Kuhl
Press and General Inquiries Email:
Project Contact Email:


Colorado School of Mines

Related Projects

Release Date: