US-based electric utility FirstEnergy, through its subsidiaries Potomac Edison and Mid-Atlantic Interstate Transmission (MAIT), has secured transmission upgrade projects worth more than $800m in the US.

Regional transmission organisation PJM Interconnection (PJM) has awarded the projects in Maryland, Pennsylvania, Virginia, and West Virginia.

The projects are expected to enhance reliability, meet the growing demand for residential and commercial electricity, and connect new energy resources such as wind and solar.

The works would increase the electricity flow across the system, mitigating the 11GW of loss through power plant retirements, adequate to power 1.1 billion LED lightbulbs.

Earlier this year, Potomac Edison and MAIT submitted the projects when PJM solicited proposals to address the growing electricity demand, particularly in Northern Virginia.

Since May this year, PJM evaluated 72 proposals and recommended a short list of projects, and its Board of Managers approved three FirstEnergy-affiliated projects.

FirstEnergy transmission vice president Carl Bridenbaugh said: “At FirstEnergy, we are committed to doing our part to make sure that the transmission system delivers the power customers depend on, and we are pleased to have the opportunity to make these important upgrades that will enhance reliability and deliver long-term benefits for years to come.”

The projects include upgrading an existing 24-mile (38km) transmission line between Adams County in Pennsylvania and Carroll County in Maryland, with a new set of 230kV wires.

As part of the $135m project, MAIT will also undertake the rewiring of a 115kV transmission line located in the surroundings and complete additional equipment upgrades.

A $235m project includes upgrading a transmission line in Frederick and Montgomery counties in Maryland to accommodate side-by-side transmission structures.

The current 500kV and double-circuit 230kV lines will be replaced with structures featuring sets of 500kV wires over 230kV wires for a total of four circuits.

A $392m project involves upgrades to a 36-mile (58km) existing 138kV transmission line in Virginia and West Virginia to install a double-circuit line with 500kV wires over 138kV wires.

The project, which also includes substation upgrades, is part of a larger 160-mile (257km) transmission line project awarded by PJM to multiple transmission companies.