You Do Need power plug adapter while traveling from Western Sahara to Chad.

Here is Why You Need An Adapter

The outlet and plug type used in Chad are C, D, E and F and in Western Sahara are C and E. This is how they look like.

Western Sahara

In Western Sahara, outlets of type C and E are in use.

Type C

Type E

Chad

In Chad, outlets of type C, D, E and F are in use.

Type C

Type D

Type E

Type F