Xcel Energy this year plans to invest about $353m to build 277 miles of new transmission lines in eastern New Mexico and South Plains in Texas, a move that will facilitate wind development and energy exports in one of the US industry’s main growth regions.

The expansion will include 128 miles of heavy-duty 345kV lines in New Mexico, a $186m investment, that Xcel subsidiary Southwestern Public Service Company targets to have in service by 30 June 2018.