Three giant transformers - each valued at over $5 million and weighing over 175,000 kg when prepared for transport - hit the road recently, as they moved from their Winnipeg factory to their new home at Manitoba Hydro's Riel Station. The transformers are being installed as part of the utility's reliability improvements on its 500-kV line linking Manitoba to Minnesota.

A special 320-tire self-propelled modular trailer (SPMT) was brought to Manitoba especially for the move. The SPMT is similar to the unit used to recently move the space shuttle Endeavour through the streets of Los Angeles. A special route, designed to avoid tight city streets and narrow overpasses, has been planned for the move.

The Transformers

Ordered by Manitoba Hydro from Alstom Grid as part of the utility's development of Riel Station on the east side of Winnipeg, and built locally by CG Power Systems at its Fort Garry factory, the three transformers will play a critical role in enhancing the reliability of the 500-kV line that Manitoba relies on for the bulk of its power exports and imports. The utility is "sectionalizing" the line, which will allow electricity to be fed into or taken from the line at more than just one point, providing a significant measure of backup.

When disassembled for shipping, each transformer measures approximately 7 m tall by 4 m wide. However, when fully assembled with bushings, insulators, cooling units and other accessories to be added on site, each transformer will stand almost 12 m tall, and measure 9.6 m across. Each transformer requires over 112,000 litres of insulating oil. The weight of each fully assembled transformer will be almost 295,000 kg. For comparison, an empty 747-400 jumbo jet weighs only 179,000 kg.

The Move

It will take three days - or more accurately three nights - to move each of the transformers to their new home, following a route that is 144 km long. The SPMT used to move the transformer will measure just over 34 m in length and be approximately 7.5 m wide. The 320 tires on the SPMT allow the tremendous weight of the transformer to be distributed evenly over a large area of road, preventing damage to the concrete and asphalt. The move will be conducted at a speed of about 5 km per hour. It is believed that this is the first time SPMTs have been used in Manitoba.