While diving with his family in Greece, 16-year-old Boyan Slat was shocked to see so much plastic in the sea. Millions of tons of plastic have littered the world’s oceans over the last few decades, and Slat was shocked to learn that there was no clear solution for cleaning up the sea. He became determined to do something about it. Rather than attempting to clean the ocean by picking up the litter, which would take thousands of years, Slat designed a system that would allow the litter to come to him. By creating an array of floating barriers anchored to the seabed, Slat’s invention would catch and concentrate floating debris, while allowing sea life to pass through it. The collected plastic could then be recycled or made into oil. Having already raised over $2 million, in 2017 Slat is set to deploy a pilot device near the Japanese island of Tsushima.