Africa's population is exploding.

By the United Nations' estimate, the continent will see its current population of 1.2 billion double by the year 2050. That's an expected growth of 42 million people — basically a brand-new Argentina — every year.

A number of important infrastructure projects are underway to make room for all those people, including railways, dams, and clean energy solutions such as solar arrays.

Here are some of the largest projects coming to Africa in the next several decades.