As lights went off at night across Seoul landmarks in celebration of Earth Day 2019, darkening the glitzy, gleaming South Korean capital, the Seoul Metropolitan Library lit up brightly with projections powered by the Hyundai Nexo.

Undulating footages highlighting the whole water-electrolysis cycle - water turning into hydrogen and oxygen, then to kinetic energy, and finally back to water - were beamed onto the building facade.

This was done using five units of the Nexo, the world's first fuel cell electric SUV from Hyundai.

The four-minute imagery was projected repeatedly for an hour, offering a new vision for future energy.

The demonstration in the heart of Seoul marks the world's first instance of its kind using hydrogen fuel cell technology. It also exemplifies an environmentally friendly method of energy generation, as the five Nexos used were charged at Sangam Hydrogen Station, which uses biogas produced from a nearby landfill to produce hydrogen.

The fuel cell stacks in these SUVs were converted to generators to supply electricity to beam projectors, which were themselves individually equipped with power inverters. According to the Seoul Metropolitan Government, the event is designed to catalyze and heighten societal discussions on environmental issues, particularly reducing fine dust and carbon footprint while accelerating decarbonisation.