You Do Need power plug adapter while traveling from Solomon Islands 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 Solomon Islands are G and I. This is how they look like.

Solomon Islands

In Solomon Islands, outlets of type G and I are in use.

Type G

Type I

Chad

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

Type C

Type D

Type E

Type F