Driving Reliability in Southern California

SCE heavy transport drivers move a mobile substation to Trona, Calif. to help keep the power flowing.

It’s 6 a.m. and Mike Minar and Gilbert Ibarra, both heavy transport truck drivers with Southern California Edison, have a long day ahead of them. Their assignment today: transport a mobile substation up north about 137 miles to the city of Trona.

Weighing in at 92,000 pounds, the mobile substation — a specially constructed trailer which contains the transformers, connections and controls needed to get the job done — is hooked onto a truck at the utility’s Grand Terrace facility in the Inland Empire before making its journey along California’s 215 and 15 freeways.

As it finally makes its way onto U.S. Highway 395, cutting through the town of Ridgecrest, it will arrive in Trona about four hours later.

“We consider everything from the condition of the trucks and trailers, to making inspections of the equipment, to planning the route,” said Minar, a 26-year SCE employee, who is very familiar with the careful planning it takes to safely move such heavy loads.

Maintenance at a substation is usually routine work for SCE. Oftentimes power is rerouted to other local circuits while repairs or upgrades are made. While this changeover takes place, customers typically experience a short outage.

But doing maintenance work in remote or isolated locations, such as a small substation in Trona, is often a more complicated process. In some of these remote areas, rerouting power to complete repairs is not an option because there may be fewer circuits and substations in those locations.

In these cases, a mobile substation is often the answer so customers will experience shorter outage times while maintenance work takes place.

And safely bringing in these mobile substations requires expert drivers. Often, the size and weight of the trailer and truck are allowed only on certain roads. Two drivers can be required because of the nature of the load and the difficult terrain where it will be delivered. And for these drivers, hard work is the payoff.

“I still like coming to work every day,” said Minar, “especially as we get to work with some great people.”

mobile substation
SCE's Searles Substation in Trona, Calif.

In the early-morning hours Monday, Minar and Ibarra connect their truck to the mobile substation and conduct their pre-trip safety checks. This includes walking the exit route from the Grand Terrace facility to ensure traffic or terrain allows them to safely exit the facility.

Ibarra notes that this will be a day trip, though drivers will do overnights on longer hauls, such as weekly deliveries to remote facilities like Bishop. Safety regulations require long-distance drivers to get a certain amount of rest each day they drive to stay alert.          

Ibarra, on the job now for seven years, will make an overnight trip to SCE’s hydroelectric facility in the Sierra Nevada to deliver equipment and supplies after he drops off the mobile substation in Trona.

“This is the best job ever,” he said.