American R&B singer Aliaune Thiam, professionally known as Akon, has long wanted to help Senegal, the country he grew up in. He started Akon Lighting Africa in 2014 to install cheap Chinese solar-powered lighting systems across the continent. He hoped to do something more significant for Senegal. But how to fund it? The answer turned out to be the same one adopted by a growing number of governments and entrepreneurs: a mixture of cryptocurrency and urban planning. It’s a combination that offers ...