Photonic Technology Converts Greenhouse Gases into Clean Energy

The European consortium SPOTLIGHT is developing a process that uses sunlight and LEDs to turn carbon dioxide and green hydrogen into clean energy products such as methane gas and methanol liquid fuel. Using a photonic device, the SPOTLIGHT consortium is looking to process up to one megaton of carbon dioxide per year, with the technology complementary to existing large-scale carbon capture and utilization processes.

“Our goal is to develop and validate a photonic device and chemical process concept for the sunlight-powered conversion of CO₂ and green H₂ to the chemical fuel methane (CH₄, Sabatier process) and to carbon monoxide (CO, reverse water gas shift process) as starting material for the production of the chemical fuel methanol (CH₃OH),” said Nicole Meulendijks, project coordinator at SPOTLIGHT. “Both CH₄ and CH₃OH are compatible with our current infrastructure and suited for multiple applications such as car fuel, energy storage, and starting material to produce valuable chemicals.”

The photonic device will consist of a transparent flow reactor optimized for light incoupling in the catalyst bed, Meulendijks said. It will include secondary solar optics to concentrate natural sunlight and project it onto the reactor. Finally, it will feature an energy-efficient LED light source to ensure continuous 24/7 operation.

The device will use plasmonic catalysts that are capable of absorbing the full solar spectrum.

The chemical processes proposed by SPOTLIGHT can be upscaled to offset the CO₂ emitted by small to medium “point sources,” or places that emit carbon dioxide at rates lower than one megaton per year.

A photonic device consisting of a transparent flow reactor, solar optics, and an LED light source. It uses plasmonic catalysts capable of absorbing the entire solar spectrum and is the central component of a process that uses sunlight and LEDs to turn carbon dioxide and green hydrogen into clean energy products. Courtesy of Photonics 21.

Worldwide there are approximately 11,000 CO₂ point sources. Combined, they emit a cumulative total of about 2.7 billion tons of CO₂, which is approximately 16% of all CO₂ point sources globally.

“Potentially, the process we envision at SPOTLIGHT could convert 2.7 billion tons of CO₂ per year into useful chemical fuels,” Meulendijks said.

The consortium is coordinated in the Netherlands by Nederlandse Organisatie Voor Toegepast Natuurwetenschappelijk Onderzoek TNO. It consists of partners from the Netherlands, Belgium, Switzerland, Germany, Italy, and Spain.