You Do Need power plug adapter while traveling from Saint Kitts and Nevis to Solomon Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Solomon Islands are G and I and in Saint Kitts and Nevis are D and G. This is how they look like.

Saint Kitts and Nevis

In Saint Kitts and Nevis, outlets of type D and G are in use.

Type D

Type G

Solomon Islands

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

Type G

Type I