Combine water and ginger in a medium saucepan; bring to a boil over high heat.
Reduce heat to medium; simmer, uncovered, 20 minutes.
Remove from heat; remove and discard ginger slices.
Add sugar, stirring until sugar dissolves.
Add tea bags; steep 5 minutes.
Remove and discard tea bags; let cool.
Stir in peach nectar; cover and chill.