Six Cat Gas Gen-Sets For S.D. Power Plant Repower

Caterpillar Inc. announced an agreement with NorthWestern Energy to supply an integrated power solution that includes six Cat G20CM34 gas generator sets for a 58 MW power plant near Huron, S.D.

The Cat G20CM34 gas generator sets will replace combustion turbines currently operating at the Huron Generating Station. By providing fast start capability and highly efficient energy production at varying load levels, Cat said the G20CM34 generator sets will deliver the capacity needed for reliable, safe, and affordable service while accounting for intermittent energy supply from renewable resources.

Caterpillar is also supplying selective catalytic reduction (SCR) emissions systems, switchgear, exhaust stacks, and control solutions for the new facility, which will be built on the current site. Additionally, the power system will be equipped with Cat Connect services, which will enable the operations staff to optimize the performance and maintenance of the plant.

Construction activities began in July, with commercial operation expected at the end of 2021. When complete, the new facility will have a smaller footprint and a larger setback than the current building.

NorthWestern provides electricity and natural gas to approximately 734,800 customers in Montana, South Dakota, and Nebraska. It has generated and distributed electricity in South Dakota and distributed natural gas in South Dakota and Nebraska since 1923, and has generated and distributed electricity and distributed natural gas in Montana since 2002.

“Caterpillar offers equipment with a successful history of quality and performance, and the generator sets will meet the energy needs of our South Dakota customers for decades,” said Jim Williams Jr., NorthWestern Energy’s director of thermal & wind generation.

Cat dealers will play a prominent role in the design and construction of the power plant. Ziegler Cat will support Fagen, Inc. of Granite Falls, Minn., which was selected as the engineering, procurement, construction (EPC) contractor. Fagen, Inc. will collaborate on engineering services with Commonwealth Associates, Inc. of Jackson, Mich., with assistance from Michigan Cat.

The Huron Generation Station is the fourth application of Cat G20CM34 generator sets in the U.S. More than 150 GCM34 engines are installed in the U.S. and Canada, representing over 1000 MW of installed capacity in power and gas compression projects.

“NorthWestern Energy is an industry leader in reshaping and diversifying its electric generation portfolio, with nearly 58% of its energy currently provided by renewable resources,” said Claudio Martino, Caterpillar’s sales manager for medium-speed reciprocating technology in the Americas. “With a fast start time, short ramp-up and ramp-down times, and low operating costs, Cat gas generator sets will help NorthWestern Energy provide reliable and efficient power to its grid.”