Carbon dioxide found popularity as a refrigerant for comfort cooling in the 1920s, before being replaced by more convenient CFCs (chlorofluorocarbons) in the 1930s and then HFCs (hydroflurocarbons) in the 1990s. But with the Kyoto Protocol, an international treaty requiring industrialized nations to lower their collective greenhouse gases 5 percent below 1990 levels by 2012, carbon dioxide has come back into the limelight as a hope for a safe and effective refrigerant replacement.
Coca-Cola is in the testing phase of CO2 refrigeration, planning commercial rollout in selected countries later this year, as CO2 equipment becomes commercially available at cost competitive prices. "Our field tests of CO2 vending machines so far have included compressors from Sanyo and Danfoss, but we are aware that other compressor manufacturers are also planning to launch their own CO2 designs," says Salvatore Gabola, director of European public affairs for Coca-Cola.