Phycoerythrin extracted from Antarctic red seaweeds shows promising characteristics to be applied as an anode sensitizer in water-splitting photoelectrochemical cells. Under light irradiation and using an LED lamp, the red-colored protein shows an interesting ability to profit the incident light, as confirmed by the presence of oxygen bubbles next to the electrode surface without applying any external potential. Our results showed that the addition of iodide is helpful to allow the regeneration of the dye; nevertheless, oxygen evolution is not favored. Thermodynamics analysis of the involved semi-reactions is also helpful to understand the observed results. The exploration of Antarctic resources offers then an alternative for the development of green energies, with a particular focus on their use as sensitizers to profit from the sunlight in water-splitting as well as in photovoltaic devices.