Finnish engineer Lukas Sjöman built a DIY solar-powered yacht called Helios 11 for approximately $20,724, then sailed it more than 3,000 nautical miles without

Finnish engineer Lukas Sjöman built a DIY solar-powered yacht called Helios 11 for approximately $20,724, then sailed it more than 3,000 nautical miles without using any fuel. The 11-meter vessel took 200 days to construct from marine plywood and fiberglass. Equipped with 10 rooftop residential sol…