UK ocean carbon capture trial scrapped over viability concerns

A controversial ocean carbon capture experiment in St Ives Bay, Cornwall, in the UK has been cancelled by the company involved as commercially unviable.

Planetary Technologies, a Canadian firm, had aimed to add diluted magnesium hydroxide (an antacid compound) into the bay via a wastewater outfall to neutralise ocean acidity and enhance carbon dioxide absorption from the atmosphere.

The approach, known as ocean alkalinity enhancement, was tested in a 2022 trial, showing potential to safely reduce CO2 levels in seawater.

An independent audit by the UK’s Environment Agency later found the method posed a very low risk to marine life at the trial scale.