Northeast Utilities, Yankee merge: Northeast Utilities, New England`s largest electric utility system, and Yankee Energy System Inc., parent of Yankee Gas Services Co., the state`s largest natural gas distribution company, have completed their merger. Yankee`s unregulated subsidiaries will change as follows: Yankee Energy Services Co. will be integrated with NU`s unregulated subsidiary, Select Energy. NorConn, Yankee`s subsidiary that leases and manages real estate for Yankee Gas, will be transferred to NU. R.M. Services and Yankee Energy Financial Services will remain part of Yankee Energy System.