Security has become a top concern for voters across the region who are calling for iron-fisted measures. In Chile, the issue is pushing the country to the right.

© Sara Wayra for The New York Times

Jeannette Jara and José Antonio Kast are facing off on Sunday in a deeply polarized election marked by concerns over security and immigration.

An early grid battery was installed in the Atacama Desert in Chile 15 years ago. Now, as prices have tumbled, they are increasingly being used around the world.