MDU is moving forward on its plans to retire three aging coal-fired generators, replacing them with natural gas units.
The plants are the Heskett Station units one and two, near Mandan – and the Lewis and Clark plant in Sidney, Montana. MDU will be installing new natural gas turbines at those plants.
The North Dakota Public Service Commission has approved a certificate of "public convenience and necessity" for the plants as well as a determination of “advanced prudence” for the facilities. The "advanced prudence" declaration will make it easier for MDU to seek financing for the new gas turbines.
"I think one of the biggest things (for the retirement of the coal units) would be age," said PSC Chairman Brian Kroshus. "These are 50-plus years old. They wear out."
Kroshus said it's at a point where MDU had to make a decision on whether it was more economical, from a rate-payer standpoint, to put additional money into those units, or retire them.
MDU is planning to retire the Lewis and Clark Coal Unit at the end of this year, and the two Heskett units in 2021.