ExxonMobil has completed construction of a pilot direct air capture (DAC) plant with which it aims to test new technologies designed to remove the very low concentrations of carbon dioxide in the atmosphere.

A rather coy chief executive, Darren Woods, told analysts during today’s fourth quarter conference call that he could not say much about the prototype due to the proprietary nature of technology, but hoped it could result in lowering the current sky-high costs of DAC.