Once the two main elements are fully assembled and online, the unit will weigh approximately 2.5 million pounds.
Because of its size, it was transported in two pieces. Each transformer piece made its way to Monticello on a 30-axle, 413-foot-long, 20-foot-wide transport vehicle with 240 tires that was pulled by one or two trucks and pushed by five other trucks.
The first piece arrived on October 27 and the second shipment arrived in Monticello on November 20, after traveling for more than one week on public highways from a rail transport center near Gallup, NM. The transformer was manufactured in China and traveled by ship through the Panama Canal and to Houston, TX. The massive equipment was on rail lines from Houston to Gallup.
It will help transport power generated at the 27-turbine Latigo Wind Farm, which is under construction north and west of Monticello.
“Planning and development of this project began in 2012,” said Deb Dull, Rocky Mountain Power regional business manager. “The new transformer will increase the capacity on the system and enhance electric service reliability for our customers. This is a phase-shifting transformer that will give the company more control and flexibility for the entire system.”
The 400-megavolt transformer is the third transformer to be placed in the Pinto substation and will allow more electricity to be transferred within the system. In addition, the new design of this transformer will better accommodate the variable nature of renewable generating resources that are seeking to interconnect to the electrical grid.
Preparing for the installation of the transformer, a concrete foundation three feet thick was constructed inside the substation. The transformer will measure 58 x 57 feet and 32 feet high and took seven months to construct.
The two sections will be put in place on the foundation and joined together using a third piece and about 40 crates of parts and pieces. Once the units are attached together, they will be connected to the electrical system.
“We expect to have the initial connections made and some preliminary testing done during December,” Dull said. “Work will continue for a few weeks and final integration onto the system is scheduled for mid-February.”
The Pinto substation was built in the mid-1970s and has been serving Monticello and southeastern Utah since that time as an integral part of the overall electric system.
“This substation upgrade enables the company to continue its commitment to reliable customer service throughout the six-state service area,” Dull said.