LONG BEACH, Calif. — The future is difficult to predict, but a boat that just docked in Long Beach is setting course on one potential path.

Powered with solar panels, wind and hydrogen generated from seawater, the Energy Observer — as it’s called — is entirely self-sustaining. It doesn’t use diesel or generate emissions. All the energy it needs is produced on board.

“The idea is to show that it works,” said Laurene Blotterre, communications director for the Energy Observer and the French team that created it.

The first vessel of its kind, the Energy Observer is making its U.S. debut this week. It docked in Long Beach on Earth Day following a month-long sea passage from the Galapagos Islands — one of 65 stopovers the catamaran has made four years into a seven-year, round-the-world exhibition. So far, it has traveled 30,000 nautical miles self sufficiently.

A floating laboratory that’s testing renewable technologies from companies large and small, the Energy Observer generates electricity using three types of solar panels covering every surface that receives sunlight. Among the 663 square feet of solar are flexible, textured tiles that can be walked on and two-sided panels that take in rays from the sky, as well as sun reflected from the water.

Wind not only helps propel the boat with a pair of sails, or ocean wings, as the team calls them. It also helps generate electricity. That energy is stored in batteries to be drawn upon when needed, as is the hydrogen gas that generates energy with a system of fuel cells.

“Hydrogen has an interesting unifying role in the boat,” said Keith Malone, spokesman for the California Fuel Cell Partnership, a public-private partnership that promotes hydrogen vehicles in the state. Not only does the boat use an electrolysis system to generate renewable hydrogen from sea water, it captures whatever excess energy is not being used for propulsion and gives it back to the batteries.

“Hydrogen has been described by many as a unifier for the renewable future. It’s able to link renewables in a way that most other things can’t. That’s very significant, so this boat really showcases that,” Malone said. “Plus, it’s just super damn cool.”