It actually worked!

But in 2002, when William was 14, his farming family could no longer afford to send him to school when Malawi was hit with its worst famine in decades. He decided to continue studying on his own, however, and chanced upon a library book about wind power. Much to the amusement of his friends and neighbors, William began constructing a homemade wind turbine from wood scraps, plastic, and old bicycle parts. But their skepticism quickly turned to wonder when William demonstrated that his contraption could provide enough energy to power lights and radios in his family’s home, when only 2% of Malawi’s residents enjoyed household electricity.

The boy's windmill is certainly much better than the "zimcopter" contraption from 2003:

Enigmatic former soldier, convict, squatter and businessman
Barnabas Sibanda aims to make aeronautical history by building a
helicopter from junk and powered by a car engine.

His first project, a ZD17000 home-made "Zimcopter", was
condemned by Zimbabwe's aviation authorities before its first test

But, undeterred, the former Zimbabwe National Army infantry
commander has set about constructing a new ZD30,000 chopper out of
aluminium sheets and an engine cannibalised from an old French
Citroen motor vehicle.

"I am married to these helicopters; they are my wives because I
work on them from before sunrise till past sunset," he told Ziana
news agency as he tinkered with his project with the zeal of a
modern-day Orville or Wilbur Wright, the brothers who pioneered
flight in 1905.

Born Jackson Sibanda to a farming family in southern Zimbabwe,
the 37-year-old self-styled pilot and aeronautical engineer is
adamant he can turn his dreams into a flying reality.

One of Sibanda's wives:

Photo by William Kamkwamba.