By Harriet McLeod
CHARLEST0N, South Carolina (Reuters) - The sailors finishing the fourth leg of a grueling, solo yacht race around the world arrived in Charleston, South Carolina, this week with sunburned faces and tales of trials on the open seas.
That's typical fare for participants in the Velux 5 Oceans Race. But sailors making the current journey have tried something new: powering their boats' high-tech electronics systems with sustainable energy from the sun, wind and water.
"The goal, of course, is not to use any fossil fuel at all," said Derek Hatfield, 58, of Nova Scotia, after placing second in the latest leg on Wednesday.
Dubbed "the world's ultimate solo challenge," the race has been held every four years since 1982 and amounts to an eight-month endurance test.
Since launching from La Rochelle, France, in October, four sailors have slept in 20-minute increments, eaten dehydrated food and tried to keep their 60-foot boats intact in some of the Earth's toughest conditions.
For the first time, they are sailing "Eco 60s" -- old Open 60 yachts that have been rebuilt and refitted with machines to capture renewable energy.
Solar panels on deck, wind generators on sterns and hydro generators in the water power the sophisticated autopilots, navigation electronics such as GPS, and wind sensors, radar, satellite phones and laptops.
"The idea of this eco concept is to make the boats economical and to use sustainability practices for making electricity on a boat," said race leader Brad Van Liew, 43, who crossed the finish line on Tuesday afternoon.
"But actually, the most eco-friendly thing is that we're recycling boats," said Van Liew, a South Carolina resident who has competed in the race twice before. "Imagine the carbon fiber that goes into building one of these boats."
The yachts still have engines on board for safety reasons and to get in and out of port, sailors said.
"So everybody carries this big, clunky diesel engine to propel the boat, but in reality you don't need it," said Hatfield, also a race veteran.
The race has been sponsored since 2006 by Velux, a Copenhagen-based company that makes energy-efficient skylights, windows and solar hot water products.
So far, the "green" boats have carried the sailors through the Atlantic Ocean to Cape Town, South Africa, then across the Indian Ocean and South Pacific and into the stormy Southern Ocean, where waves can top 30 feet.
They sailed below Australia to Wellington, New Zealand, and then through remote waters to round Cape Horn and land in Punta del Este, Uruguay.
The fourth leg took them up the coast of Brazil and past the Caribbean Islands to Charleston.
Third-place finisher Chris Stanmore-Major of Britain was expected to arrive in Charleston late Thursday.
Polish sailor Zbigniew "Gutek" Gutkowski broke a rib at sea soon after the March 27 start from Uruguay and had to go into port at Brazil. He is expected to restart the race this week.
The final leg begins on May 14 and finishes in La Rochelle in June.
Armchair sailors can follow the boats on an interactive satellite map of the world that shows their position and speed at www.velux5oceans.com. Videos and audio interviews by the skippers also are posted on the race website.
Those who have sailed the race before reported seeing a changed ocean environment with warmer waters and fewer dolphin and whale sightings.
"The sea is becoming like a desert," Hatfield said. "It really is very barren."
"I'm not an environmentalist, or I don't thump it too hard, but I am there," Hatfield said. "Things have changed a lot more than we think. I hope it's not too late. I hope that we can make a difference."
(Editing by Colleen Jenkins and Jerry Norton)