The Mica hydroelectric plant is one of the largest earth-fill dams in the world, operating since the mid-1970s with a generating capacity of 2,805 megawatts (MW). It is one of British Columbia’s (BC) largest power generation facilities accounting for about 22 per cent of the generating capacity of the provincially-owned power utility, BC Hydro, and producing power for more than 650,000 homes each year.

Some of the ultra-high-voltage equipment in the Mica underground powerhouse is reaching the end of its useful life and as part of an upgrade, leading Canadian utility BC Hydro has decided to replace the plant’s Generator Step-Up (GSU) transformer banks with ABB’s flexible tank technology to mitigate the risk of tank rupture. GSU transformers provide a critical link between the power station and the transmission network.

The GSUs of the Mica powerhouse are located is an underground facility with very limited space – so minimal equipment size is critical. ABB’s unique solution provides superior safety features in a smaller footprint than similar units fitted with alternative protection systems.

“We are pleased to continue our longstanding collaboration with BC Hydro. This project enables us to support our customer in their ongoing efforts to bring safe and reliable power supply to consumers,” said Markus Heimbach, Managing Director of ABB’s Transformers business unit, a part of the company’s Power Grids division. "It also reaffirms our commitment to creating differentiated value for our customers through our state-of-art technologies."

ABB’s scope of supply for the $28 million order includes the design, manufacture and supply of single phase, 176-megavolt ampere (MVA) 500-kilovolt (kV) transformers, to be manufactured at ABB’s transformer facility in Varennes, Quebec. ABB’s transformer portfolio includes HVDC and power transformers rated up to 1,200 kV, dry- and liquid-distribution transformers, traction and special application transformers as well as related services and components.

Transformers are integral components of an electrical grid and essential for the efficient and safe conversion of electricity between different voltage systems. Transformers are crucial pieces of equipment that are primarily used to step up or step down single- or three-phase line voltages to desired levels and keep power flowing smoothly.