You Do Need power plug adapter while traveling from Tuvalu to Turks and Caicos Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Turks and Caicos Islands are A and B and in Tuvalu is I. This is how they look like.

Tuvalu

In Tuvalu, outlets of type I are in use.

Type I

Turks and Caicos Islands

In Turks and Caicos Islands, outlets of type A and B are in use.

Type A

Type B