The world's largest solar-powered vessel set sail from Monaco for an all around-the-world trip.

The 60 tonne ship, named 'Planet Solar', is 31-meters long and 15-meters wide and is decked with photo-voltaic modules.

The special batteries allow it to sail for about three days without fresh solar power. The ship cost 10 million euros and took fourteen months to build.

It can reach speeds of up to around 28 kilometers per hour. The point of this trip is to show that solar power is a viable source of energy for transport. The six crew hope to make it around the world in 160 days.