Plymouth (United Kingdom) (AFP)

Two weeks cramped, eating freeze-dried food with a toilet bucket: Trans-Atlantic cruise of young climate defender Greta Thunberg on a small racing boat to rally New York will be low in carbon emissions but also in comfort .

But this Tuesday in Plymouth, the eve of her departure except weather, the 16-year-old Swede is ready for the crossing with the only non-polluting means of transport that can take her to the summit on the UN climate.

"I tried the yacht yesterday and it was a lot of fun, it's going to be a hell of a lot of adventure," she told AFP aboard the Malizia II, an 18-meter racing boat moored in the port of Plymouth, in the south of the United Kingdom.

It was her first experience aboard a sailboat and she was seasick. "That was to be expected," she comments.

Pierre Casiraghi, son of Princess Caroline of Monaco, has made the boat available for free for 3,000 nautical miles, and will manage it with the German skipper Boris Herrmann.

Malizia II, a racing monohull with foils that keep it out of the water, was built in 2015. It is equipped with solar panels and underwater turbines to generate electricity that powers the navigation instruments, the autopilot, watermakers and a laboratory to test the CO2 level of the water.

The interior is dark, narrow and functional. It has been slightly modified to accommodate Greta, his father Svante and a filmmaker, with two hammock berths, mattresses and curtains.

A small gas stove to heat the water needed for freeze-dried vegan food is the only consumer of fossil energy.

The toilet: a blue plastic bucket with degradable bio bag that can be thrown overboard.

"It's like when you're camping in the mountains, a mattress, a sleeping bag, a flashlight and that's it," says the skipper.

- A "crazy" trip -

He recognizes that it may seem "crazy" to board three novices for such a difficult journey, but ensures not to fear for their safety, only for their comfort.

Herrmann has traveled around the world three times and will be supported by a team on shore who will follow the movements of the boat and the weather.

The yacht can go up to 35 knots (70 km) per hour but the skipper intends to take it to 10 knots (20 km) per hour during the crossing. And he will take a road a little longer than usual to avoid the storms.

The Malizia II was designed for racing, but with a 4.5-meter keel there is little chance of it turning around.

"Safety is not a problem," says Herrmann, making final preparations. "It's mostly something that has never happened before, that someone without sailing experience crosses the Atlantic on such a boat".

"It says a lot about Greta - she does a lot of things that have never been done before," he adds.

The person concerned is not afraid - except to embarrass others. "I think I'm going to read a lot, and contemplate the ocean, and go for a ride on the boat," she says.

The sailboat has a rudder that can be used manually but the onboard technology makes its handling closer to that of an airplane.

"Once the autopilot starts, the boat goes ahead, we look at the weather forecast, the production and consumption of energy, we check that everything works, we have the eye to everything," says Herrmann.

"Everyone watches in turn, hour by hour, we alternate to sleep," he adds, concluding: "The goal is to arrive safe and sound in New York."

© 2019 AFP