A movie premiering in Berlin tells the true story of a young boy from a famine-stricken village in Malawi who studies books about energy then builds a wind turbine that enables farmers to irrigate their land.
Directed by Chiwetel Ejiofor, "The Boy Who Harnessed the Wind" tells the story of William, an engineering enthusiast who resorts to secretly using the school library to learn when he is expelled from school because his father - a poor farmer - cannot afford to pay the fees.
The farm land around the village gets flooded, ruining the crops, and then later dries out, leaving people with hardly any food. Desperate villagers steal food from William's family and they end up with just enough for one meal per day.
Less educated villagers doubt William's turbine idea will work and his father initially refuses to give him the bike - one of the family's few possessions - that he needs to make it, telling him to start helping on the farm instead of studying.
The father later gives in and William uses the bike, some wood and junk that he finds in a scrapyard to build the towering construction that powers a water pump. At the end of the movie, he climbs the turbine to see green plants shooting out of what was previously dry, cracked and barren land.
"I was struck and continue to be struck by just what an extraordinary achievement it was," Ejiofor said. "What his story represents is really living in the solution, not living in the problems."
The film is based on an autobiographical book with the same title written by the real-life William Kamkwamba. Kamkwamba said he hoped people who had not read the book would see the movie and learn about his story, adding: "They might get inspired by my work that I did, so I'm very excited."
Maxwell Simba, who plays William, said he was struck by William's determination to fight for what he believes in despite his difficult relationship with his father and despite being expelled from school.
"If you are really determined to go get what you want, then the universe has its own way of working out for you to achieve at the end of the day what you wanted to achieve," he said.