COLUMBIA, S.C. (AP) — After more than year of wrangling over competition concerns, federal regulators have cleared Duke Energy’s proposed takeover of Progress Energy, a deal that will create the nation’s largest electric utility.

The Federal Energy Regulatory Commission’s ruling, issued Friday, does impose some additional conditions on the merger, including requiring regular status updates on transmission upgrades. FERC stipulated that the upgrades must be completed by June 2015 and not charged to wholesale customers.