Wärtsilä is to help Loup River Public Power District reduce its lifecycle costs at its Monroe powerhouse by converting the oil lubricated seals and bearings to water-lubricated equipment.

The conversion of the first turbine shaft will take place this summer, with the remaining two turbines to be converted in 2017, together with the installation of a Water Quality System.

Loup Power, located in the US state of Nebraska, is a public utility that produces hydropower for four counties via its two power plants, the Monroe and Columbus Powerhouses, which produce a total of 56MW. Both are located on a canal system which diverts water from the Loup River.

Loup Power has experienced challenges with its existing turbine seal solution. It has been prone to grooving leading to water entering the guide bearing, mechanical failure and turbine downtime. A move to a more reliable seal and bearing solution is of significant interest to the Loup River Public Power District.

"Wärtsilä offered a complete package that we could not find anywhere else: seals, bearings and services from the same provider," said Brad Morton, Hydro Superintendent from Loup River Public Power District. "The Water Quality System will provide lubricant water for the three turbines conveniently from the canal. All-in-all, this is a great combination that will improve reliability and reduce downtime as well as future maintenance costs."

Limited space and costs associated with a complete tear-down required the turbine and shafting to remain in place. Wärtsilä needed to come up with a solution that would allow the shaft to remain in-situ for the conversion. The challenge was solved by choosing seals and bearings with a split design. The bearing and seal segments can be easily installed in small spaces, facilitating installation and maintenance operations, it said.