Potomac Electric

(POM)

plans to acquire

Conectiv

(CIV)

, the holding company for

Delmarva Power & Light

and

Atlantic Energy

, in a cash and stock deal valued at $2.2 billion, or $25 a share.

Shares of Conectiv traded at a 52-week high of $22.05, up 5%, or $1.05, while Potomac Electric gained 24 cents, or 1.1%, to $21.59 in recent

New York Stock Exchange

trading.

The energy concerns expect to complete the merger in 12 months and plan to form a new holding company for their combined operations. The new company will serve 1.8 million customers in Delaware, Washington, D.C., Maryland, New Jersey and Virginia.

John M. Derrick Jr., Potomac Electric's chairman and chief executive, will be chairman and chief executive of the new holding company. Howard E. Cosgrove, chairman and chief executive of Conectiv, plans to retire after the completion of the merger.