You Do Need power plug adapter while traveling from Uruguay to Grenada.

Here is Why You Need An Adapter

The outlet and plug type used in Grenada is G and in Uruguay are C, F and L. This is how they look like.

Uruguay

In Uruguay, outlets of type C, F and L are in use.

Type C

Type F

Type L

Grenada

In Grenada, outlets of type G are in use.

Type G