Cerium – turning sun light into fuel

Published 15 MAY 2014 on KITCO News

The future of fossil energy resources, exploitation and geo-political importance have been a focal point since mankind invented automobiles and aero planes. A new invention promises independence from geological availability by creating kerosene from sunlight.

Explaining the technology to Tech Metals Insider were Valentin Batteiger and Christoph Falter, researchers at Bauhaus Luftfahrt (BHL) of Germany. BHL was founded in 2005 as a think tank on future technologies and the ecology of aviation by Airbus Industries, IABG, MTU, Liebherr and the Bavarian Ministry of Ecology and Transportation. Together with prominent partners including the ETH Zurich, the German Center for Air and Space Travel (DLR), Shell and ARTTIC, SOLAR-JET was born to develop a technology for the sustainable production of kerosene.

3The SOLAR-JET process consists of two stages: naturally occurring carbon dioxide and water are converted into a hydrogen/carbon monoxide mixture using sunlight and a reactor. The center piece of the reactor is made of cerium dioxide, allowing the cerium to be part of the reaction while preventing it from melting or evaporating at the high reaction temperatures that occur.

In a second stage, the gas is converted to kerosene using the Fischer-Tropsch process that is already in use.

At this point, “proof of concept” was achieved by successfully producing kerosene using a laboratory reactor of 10cm diameter (pictured) capable of absorbing 4kW of solar power. Its next stage, scheduled to be available by 2017, will absorb 50kW of solar power under actual operating conditions using “real” sunlight, explained Batteiger. It would also integrate the two production steps into one functional unit. A full scale rollout of the process will take much longer. The researchers expect that this will happen around the year 2040.

To achieve industrial viability, the system would have to be able to produce at least 1,000 barrels of fuel per day. “At this point it is not clear whether an array of reactors mounted to solar dish concentrators or a tower-like structure will be used”, said Batteiger.

The main advantage of the alternative fuel is that it can be used interchangeably with conventional kerosene meaning that already approved propulsion systems can be used. And while it does not remove the issue of fuel burning turbine engines it will contribute to more sustainability, and a reduction of greenhouse gases.

“The availability of ceria is an issue”, Batteiger added. “If we assume that our technology will completely replace conventional kerosene in the future, which will not happen soon but which is possible, then we will need considerable amounts of cerium oxide. In this scenario of a large scale rollout ceria in the amount of the current annual production volume would be required”. Luckily, the ceria is not consumed or lost in the reaction so this would be a temporary event.

(Picture: SOLAR-JET)