S&P Global Market Intelligence presents a periodic rundown of selected ratings actions on energy companies. The changes, confined to upgrades, downgrades and changes in outlook, are listed by announcement date in reverse chronological order.

Dec. 11

* Enbridge Inc. may see its credit ratings and those of several subsidiaries upgraded by Moody's as the Canadian pipeline operator moves to simplify its corporate structure.

Dec. 10

* S&P Global Ratings affirmed the ratings of Hydro One Ltd. and Avista Corp., after the Washington Utilities and Transportation Commission denied the approval of Hydro One's $5.3 billion proposed acquisition of Avista.

Dec. 6

* Moody's is maintaining its stable outlook for the U.S. public electric utility sector in 2019, citing the industry's self-regulated cost recovery mechanisms, strong financial metrics and a competitive product.

* Moody's upgraded NRG Energy Inc.'s corporate family rating to Ba2 from Ba3 and its senior unsecured rating to Ba3 from B1, with a positive outlook. The rating agency also affirmed the company's senior secured rating at Baa3.

Dec. 5

* S&P Global Ratings revised its outlook on Emera Inc. and its subsidiaries to negative from stable.

Dec. 3

* Moody's revised the ratings outlook for Edison International and subsidiary Southern California Edison Co. to negative from stable. The rating agency also affirmed the Baa1 issuer rating of Edison International and the A3 issuer rating of SoCalEd.

* S&P Global Ratings assigned an issuer credit rating of BB to Equitrans Midstream Corp., following the latter's announcement to acquire full ownership of EQGP Holdings LP in a bid to simplify its midstream family of companies. The outlook is stable.