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Photo: Olivier Coste
How One Man Uses Solar Engineering to Defy Human Limits

Olivier Coste dares to do what few have done before.
Crossing a desert by oneself, on foot, and with minimal equipment may sound like an impossible mission… but Olivier Coste of Sisyphe Explorer takes this challenge on excitedly. Olivier likens the desert landscape to flames in a fire pit—though harsh and unforgiving, it exudes pure beauty. In between the hills and valleys of torched sand, there’s a thrilling sensation of “living every moment in between fear and ecstasy.”

Olivier first began his treks through the desert with his brother. After reaching the limits of their bodies under the weight of supplies, they began wondering how to carry necessities to hike longer distances. “For thousands of years, man has traveled the world carrying resources on his back, with animals and, most recently, with motorized vehicles. However, these all have limits—food, water, fuel,” Olivier says. The solution, they realized, was shining down upon them. Inexhaustible solar energy could be the solution to how they push more than 200 kilograms (440 pounds) of gear up and over rolling sand dunes.

Olivier explained his task to Jean Pascal and his company OZO, a Sunforge partner that manufactures electric engines and batteries. Jean explained that Olivier’s primary problem would be fully charging his battery—because he is constantly bumping along uneven ground, the orientation of his solar panel would never be optimal.

Jean’s solution? “We have a new product, the GVB-8 Boost Controller from Genasun that can charge your 36V battery with your 12V panel,” he told Olivier. “It’s also the only MPPT charger that can calculate the optimal power point 15 times per second. Even if you momentarily pass through shade, no power will be cut.” Genasun controllers are also a prime candidate for Olivier’s needs because of their reliability and high performance despite harsh conditions.

Three years later, Olivier’s first rolling solar cart prototype reached completion. The solar cart is not designed to operate completely autonomously, but greatly reduces the effort needed as Olivier attaches it to his body and pulls.

In winter of 2015, Olivier traveled to Morocco to test his contraption. The Sahara desert, the largest in the world, has sparse vegetation and little animal life. Temperatures can become freezing at night. As Olivier faced the vastness of this harsh landscape, he was preoccupied with one question: “Would the solar panel be able to charge the battery enough while he moved throughout the day?” If not, he wouldn’t be able to pull all his equipment alone.

The results were immediate. “No matter what orientation the solar panel was in, the battery was constantly charging,” Olivier wrote. “I could even take advantage of the last rays of the sun to charge. On flatter ground, where the battery required little energy to move the solar cart, the battery was still fully charged at the end of the day—despite only having a 12V/ 8A panel for a 36V, 25000AH battery. It was a total success!”

In February 2018, Olivier again managed the impossible by crossing from the south to north side of the Badain Jaran desert in China. Badain Jaran is home to dunes that tower at more than 500 meters (1,600 feet)—some of the largest on Earth. Olivier Coste became the first person to ever cross the third tallest dune in the world with a solar device.

As Olivier sat back to rest after a long day, he looked over at his solar cart. “After having pitched my tent shortly before sunset, drinking my coffee facing the last of the sun’s rays before the cold night, I knew even then in the dying light that my battery was still charging a little for the next day,” he wrote. “The blinking of the Genasun MPPT Boost controller indicated that it was operating until the last drops of sunlight. And in a few hours, it would exploit the first light of dawn. Every moment counted, and the Genasun controller used each of them.”

We’re proud to be part of journeys like these that test the limits of human determination and imagination. Follow along with Olivier’s adventures on his website, https://sisyphe-explorer.com/. He plans to tackle Madagascar next, with a portable GVB-8-powered solar bag in place of his trusty solar cart.

Olivier Coste selfie with his solar-powered cart with genasun controllers
Photo: Olivier Coste