Yellowstone Electric Co. based in Billings, Montana, awarded Siemens a contract for the delivery of 14 power transformers. The transformers, which contain environmentally friendly ester as an insulating fluid and coolant, are expected to be used for the Glen Canyon Dam power plant, part of the National Recreation Area in Page, Arizona. The operator of the power plant is the U.S. Bureau of Reclamation. The new transformers will replace the technology installed when the hydroelectric power plant first went into operation and will provide for a greater real power transmission capacity. With the upgrade in the energy infrastructure, the dam and the Glen Canyon hydroelectric power plant will be able to produce approximately five billion kilowatt hours of power annually and will supply electricity to 5.8 million customers. Siemens will begin delivering the transformers in late 2017. The units are expected to be installed and begin operation in 2018 and 2019.

The ester fluid transformers supplied by the Siemens factory in Linz, Austria and with a rated capacity of 125 MVA (10 units designed for 345 kV and 4 units for 230 kV) will connect the Glen Canyon power plant to the transmission grid and increase the transmission power capacity to provide stable, reliable electricity to customers. This project is the first time the Bureau of Reclamation will use ester fluid transformers of this size for a hydroelectric power plant. The synthetically produced ester fluid offers significant environmental benefits compared to the petroleum-based mineral oil counterparts typically used in power generator step-up (GSU) transformers. The ester fluid is fully biodegradable, operates at a much higher flash point which results in a lower fire risk and can dissipate in water quickly if necessary.

“Yellowstone Electric is very proud to have been selected by the U.S. Bureau of Reclamation to execute this project with Siemens. Together, Yellowstone and Siemens are partnered to provide the Bureau with the latest in environmental technology to solve a potential problem that has existed on the Colorado River since 1964,” said George Haddenhorst, vice president of Yellowstone Electric Co. “Siemens leads the pack in ester filled transformer technology, and this project will showcase how environmental concerns can be eliminated using the best currently available technology, while at the same time, upgrading system capacity and reliability.”

“Hydroelectric generation is our nation’s largest producer of renewable power, so we need to ensure the systems that support this integral resource are operating efficiently and reliably while keeping environmental and sustainability concerns at the top of our minds,” said Richard Boyd, vice president of Siemens Transformers U.S. “Our goal in working with the Bureau of Reclamation and Yellowstone Electric Co. was to address these issues, and we’re proud that our new ester fluid transformers will enhance the integral power infrastructure for the dam and do so in the most environmentally conscious way possible.”

Siemens is a global leader in alternative oils in power transformers, manufacturing and installing the environmentally-friendly units for electrical infrastructure projects around the world.

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