Tucson Electric Power Co. completed several upgrades to its transmission system to improve service reliability and help meet future energy needs.

The Fortis Inc. subsidiary completed a $14 million project to build the 138-kV Orange Grove substation. The substation houses a transformer that will reduce the voltage of electric current from the transmission system and also connect the existing 138-kV transmission lines.

The utility also completed a $10 million upgrade of Vail Substation that includes new breakers, electrical switches, protective devices and communications equipment, a $2.4 million upgrade of the Rancho Vistoso substation, a $1 million upgrade of an existing 138-kV transmission line that connects its Irvington substation to the 22nd Street substation, and a $2.8 million upgrade of the 138-kV transmission line that connects the North Loop substation to the Rancho Vistoso substation.

Elsewhere, Tucson Electric is upgrading new overhead and underground lines as part of an approximately $1 million project in the Midvale Park neighborhood.

The company plans to invest about $260 million in 2018 to upgrade its electric transmission and distribution facilities and other resources.

Tucson Electric Power serves approximately 424,000 electric customers in southern Arizona.