Team creates fuel from sunlight

A team of researchers from UNSW Sydney has come up with a novel way to produce synthetic fuel — directly from sunlight. The process involves using light and heat to induce a reaction that creates synthetic methane from CO₂.

By leveraging renewable energy to power the conversion process, this method could help to reduce reliance on fossil fuels.

The research was led by a team from UNSW’s School of Chemical Engineering: Professor Rose Amal, Dr Priyank Kumar, Dr Emma C Lovell, Yi Fen (Charlotte) Zhu, Associate Professor Jason Scott, Dr Bingqiao Xie and Dr Jodie A Yuwono. It has been published in EES Catalysis.

“Methane is the major component of natural gas, and already widely used as a source of fuel, but is also a powerful greenhouse gas. Creating synthetic methane using only the natural resource of the sun is a cleaner and greener alternative for usage in heavy transportation, shipping and other specific industries where gas usage is essential,” Lovell said.

“By employing specific catalysts and support materials, we have demonstrated a new pathway for visible light to drive the conversion of CO₂ into methane. This not only contributes to the reduction of carbon emissions, but also adds value to the captured CO₂ by creating a valuable chemical product.”

A closed-loop system

The transformation of waste CO₂ into synthetic fuel creates a circular fuel economy — a closed-loop system that addresses environmental concerns while lessening reliance on fossil fuel extraction. The process also has the benefit of being relatively cheap, as the efficient utilisation of sunlight offsets power consumption and associated overhead costs for the reaction. This leads to reduced production costs for synthetic fuel, making it more economically viable and accessible.

“Being able to directly use sunlight reduces the costs required for energy generation to facilitate the reaction. This alleviates one of the major challenges in the pursuit and application of CO₂-derived fuel, which is contingent on the availability of low-cost, low carbon energy inputs,” PhD candidate Zhu said.

Beyond fuel production

The team is currently applying their research to the creation of other high-value chemicals, potentially benefiting a wide range of industries from fuel production to pharmaceuticals.

“One of the most promising aspects of this research is its potential impact on industries like fuel production, cement manufacturing, biomass gasification and pharmaceuticals. I would say it represents a more sustainable fuel alternative by closing the carbon loop,” Scott said.

“In terms of converting the CO₂ into value-added products, this represents a much cleaner alternative than products which currently rely on fossil fuel-derived precursors for their manufacture.

“Looking ahead, we are already envisioning a new future direction.”

Scott added that the biggest challenge lay in being able to effectively introduce the light into a larger-scale system to illuminate the particles completely. “We are exploring methods such as harnessing sunlight to drive multiple phenomena simultaneously, like solar-thermal alongside light assistance,” he said.

“Currently, we are conducting experiments at the lab scale, aiming to advance to demonstration/prototype scale within approximately a year. Following that milestone, our goal is to transition to pilot scale and ultimately to commercial/industrial scale.”

The research resulted from a collaboration between the UNSW School of Chemical Engineering and School of Photovoltaic & Renewable Energy Engineering, the University of Adelaide and CSIRO.

Image credit: iStock.com/bruev