You Do Need power plug adapter while traveling from Greenland to South Africa.

Here is Why You Need An Adapter

The outlet and plug type used in South Africa are C, M and N and in Greenland are C, E, F and K. This is how they look like.

Greenland

In Greenland, outlets of type C, E, F and K are in use.

Type C

Type E

Type F

Type K

South Africa

In South Africa, outlets of type C, M and N are in use.

Type C

Type M

Type N