Limiting global warming to 2 degrees Celsius will require not only reducing emissions of carbon dioxide, but also active removal of carbon dioxide from the atmosphere. This conclusion from the Intergovernmental Panel on Climate Change has prompted heightened interest in "negative emissions technologies."

A new study published June 25 in Nature Climate Change evaluates the potential for recently described methods that capture carbon dioxide from the atmosphere through an "electrogeochemical" process that also generates hydrogen gas for use as fuel and creates by-products that can help counteract ocean acidification.

First author Greg Rau, a researcher in the Institute of Marine Sciences at UC Santa Cruz and visiting scientist at Lawrence Livermore National Laboratory, said this technology significantly expands the options for negative emissions energy production.

The process uses electricity from a renewable energy source for electrolysis of saline water to generate hydrogen and oxygen, coupled with reactions involving globally abundant minerals to produce a solution that strongly absorbs and retains carbon dioxide from the atmosphere. Rau and other researchers have developed several related methods, all of which involve electrochemistry, saline water, and carbonate or silicate minerals.

Read more at University of California - Santa Cruz