FREETOWN, Sierra Leone — Their house was gone. They weren’t at the hospital or the morgue. Even as he searched the news for their faces, the teenager knew: His adopted family — the people who’d given him a bed when he was sleeping under a bridge — didn’t survive the mudslide.

Three days of downpours, heavy for Sierra Leone’s rainy season, had given way to reddish brown muck streaming down the residential slopes of Sugarloaf mountain. Sinkholes opened. People in this hilly capital reported hearing a crack — like thunder, or a bomb — before the earth collapsed.

Alhaji Siraj Bah, now 22, might have been there that August morning in 2017 if his boss had not put him on the night shift. He might have been sharing a bedroom with his best friend, Abdul, who he called “brother.”

Instead he was sweeping the floor of a drinking water plant when 1,141 people died or went missing, including Abdul’s family.

“All I felt was helpless,” he said, “so I put my attention into finding ways to help.”

Four years later, Bah runs his own business with nearly three dozen employees and an ambitious goal: Reduce the felling of Sierra Leone’s trees — a loss that scientists say amplifies the mudslide risk — by encouraging his neighbors to swap wood-based charcoal for a substitute made from coconut scraps. Heaps of shells and husks discarded by juice sellers around Freetown provide an energy source that requires no chopping.

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His enterprise, Rugsal Trading, has now produced roughly 100 tons of coconut briquettes, which, studies show, burn longer for families who do most of their cooking on small outdoor stoves. One report in the Philippines found that a ton of charcoal look-alikes fashioned from natural waste was equivalent to sparing up to 88 trees with 10-centimeter trunks.

“My motivation is: The bigger we grow, the more we can save our trees,” Bah said on a steamy afternoon in the capital, chatting between coconut waste collection stops. “The hardest part is getting the word out about this alternative. Everyone loves charcoal.”

The view of a hillside outside the Mortormeh community. On August 14, 2017, rocks, debris and mud flowed from above, destroying hundreds of homes and killing more than a 1,000 people in Freetown, Sierra Leone.

Researchers weren’t sure what triggered the worst natural disaster in the West African country’s history, but some pointed to Sugarloaf mountain’s vanishing greenery. Deforestation not only releases more carbon dioxide into the atmosphere — it weakens slopes. Canopies are critical for soaking up rain and taming floods. Roots anchor the soil together.

But Freetown’s mounts were going bald as people collected timber to clear lots for housing and make charcoal, the top cooking fuel in a nation where electricity is often unreliable. Sierra Leone has lost 30 percent of its forest cover over the last two decades, according to Global Forest Watch, an international tracker.

Bah had noticed men in his neighborhood harvesting wood practically every day. Many burned it to produce bags of charcoal. Most people he knew cooked with it.

What if he could change that?

Alhaji Bah, 22, the chief executive of Rugsal Trading, walks to his factory in Newton, Sierra Leone, on Oct. 6. Meanwhile, employees sort through coconut waste at the factory.

Growing up, Bah fixated on inventors. His idol was Mark Zuckerberg, chief executive and co-founder of Facebook. When he was ten, according to his mother, he pledged to create the next big thing. His father, a driver, died two years later, and the family ran out of money to take care of Bah and his sister.

So at 12, he sneaked away from home in his eastern village, hitching a ride to Freetown.

“I saw it as the promised land,” he said. “I thought if I could make it here, I could support my whole family.”

Bah lived on the streets for four years, washing cars for food. Then he met Abdul on a soccer field and the pair became close. He moved in with the boy’s family for nine months before the mudslide struck.

“After that, he was always on YouTube,” said Foday Conteh, 23, who met Bah when they were both living on the street. “He became obsessed with looking for ways to stop deforestation.”

Bah, 17 at this point, saw a video of a man in Indonesia who crafted charcoal replacements from coconut shells. Others were doing something similar in Ghana and Kenya: Collecting coconut scraps, drying them out in the sun, grinding them down, charring them in steel drums.

He watched the makers mix the blackened powder with binders like cassava flour and then feed the dough into a machine that spits out matte loaves. Next came slicing the loaves into cubes. You could grill with them the same way — except a coconut aroma fills the air.

“It looked like a great business idea,” Bah said. “I could make fuel with stuff we find on the street.”

He kept researching the concept on his boss’s computer. The machine cost about $3,000, so Bah asked for more hours and a raise. (His boss’s wife, Ejatu Sesay, recalls: “He was so young, but he was determined.”)

The wages alone weren’t enough, spurring him to follow the blueprint of another young entrepreneur he’d read about in Uganda who’d started a recycled bag business with $18. Bah saved up for scissors and glue. He visited shops around town, offering to sell bags fashioned from discarded paper for customers who would pay half up front.

One hotel manager agreed, and Bah suddenly had the capital to make a thousand bags. The order took five days to complete and netted him $100. More clients emerged. Within a few months, he bought the machine he needed to churn out the coconut briquettes.

Employees at Rugsal Trading work on Oct. 6. Rugsal Trading employees work on creating coconut briquettes. The company has grown from a one-room house to eight acres of land outside the city.

First Bah needed coconut waste. Lots of it. Juice vendors discarded the shells around the city. He bagged them up and studied instructions online.

The Indonesian man on YouTube said the briquettes would smolder twice as long as charcoal, and a study in Ghana backed up the claim. That was Bah’s selling point: A typical buyer, he knew, wanted to save cash — benefiting the environment would be an added bonus.

He pitched the product to his regular paper bag customers and eventually a restaurateur agreed to give them a try. Her verdict: They were duds that fell apart. She returned Bah’s product.

The young entrepreneur had to start over.

He reached out to a businessman in Ghana, who’d launched something of a coconut briquette empire. Sulley Amin Abubakar, 35, had been fed up with seeing coconut shells around his nation’s capital, Accra, so he dropped out of law school, thinking he’d build a waste management company before realizing the debris could be a cheap energy source.

An employee slices coconut briquettes at Rugsal Trading, while newly made briquettes dry in the sun.

“Alhaji seemed so passionate, like he actually wanted to make a difference,” Abubakar said, “and myself alone cannot supply all of Africa.”

He shared tips and critiqued Bah’s process. They discussed a shared belief: “When the last tree dies,” Abubakar said, “the last man dies.”

Bah’s second attempt proved successful. His roster of clients grew to include grocery stores around Freetown. He left the factory and built an aluminum shack on the outskirts of the capital. He named the operation Rugsal Trading — after his mother, Rugiatu, and his father, Salieu — and applied for grants across Africa and the United States.

The United Nations named him a “Young Champions of the Earth” finalist in 2019. He received an invitation the following year to pitch at a start-up conference at Harvard Business School, where he won a $5,000 prize. The money funded more equipment and employees, but he lacked teammates with expertise.

Bah paid for his friend from the street, Conteh, to attend university — there was his accountant — and linked up with his now-girlfriend, Adama Jalloh, a business student he met on Facebook. She became Rugsal’s director and won a Nigerian pitch-a-thon that netted them about $12,000.

Bah stands in a small chicken coop with his mother Rugiatu Bah. A sign outside of Rugsal Trading's building. A rooster stands at the entrance to Rugsal Trading.

Rugsal grew from one room to eight acres of land outside the city.

On a recent morning, Bah, sporting an orange jumpsuit, strolled through his property — through plots of tomatoes and bell peppers, and past chicken coops — to a clearing where two workers hauled coconut shells into steel drums.

His mother, Rugiatu, greeted him with a smile. Bah moved her here from the village.

Nearby, four other employees in a concrete shed manned three briquette machines, crushing husks into the grinder with a tool that resembled a baseball bat. Another man, squatting on the ground, sliced the loaves into cubes. After they dried in the October heat, Bah tested each one with a stomp. Anything that crumbled under his boot failed inspection.

The business churned out nine tons that month.

“I was a homeless boy,” Bah said, “and now, on a good month, we do $11,000 in revenue.”

“He was always like this,” she said. “He wanted to do something big.”

Deforestation still worries him. Charcoal remains king in Africa — the continent accounts for 65 percent of global charcoal production — and people haven’t stopped hacking down trees on Sugarloaf mountain. Sierra Leone’s president was among the 100 world leaders who vowed to halt deforestation by 2030 at this year’s United Nations climate summit in Glasgow, and Bah hopes he sticks to his word.

“We have a lot more to do,” Bah said.

He just ordered an assembly line from China, which would allow the company to make eight tons of briquettes an hour. It should arrive by February. Bah plans to expand into Guinea and Liberia. His neighbors also have endangered forests.

Abdul Samba Brima in Freetown contributed to this report

Photo editing by Olivier Laurent. Illustration animation by Emma Kumer. Copy editing by Brandon Standley. Design and development by Andrew Braford.