Making chemicals in an electrochemical cell is not new. What is new is Liquid Light’s process for converting carbon dioxide, water, and solar energy into a precursor for plastic water bottles.

Electrochemistry has been practiced for decades to make chlorine and caustic soda from salt-laden water. Like the chlor-alkali process, Liquid Light’s system is an aqueous-based system, points out Emily Cole, chief science officer and a Liquid Light founder.

But in a twist on the old technology, Cole and her colleagues at the Princeton University spin-off are taking a gas implicated in climate change—CO₂—and a clean energy source to make environmentally friendlier replacements for industrial chemicals. For its first commercial product, the firm is seeking to make ethylene glycol, one of two monomers used to create polyethylene terephthalate (PET) for water and soda bottles. The other monomer is terephthalic acid.