Whitehorse and the rest of the Whitehorse-Aishihik Faro system were without power for a short while Tuesday afternoon, as Yukon Energy's problematic fourth wheel hydoelectric governor failed again.

Two weeks ago, the governor, which controls how fast the generator spins, failed and caused a power outage that lasted two hours in some regions.

At the time, Yukon Energy spokesperson Janet Patterson had said crews identified and fixed the problem with the governor.

'They thought they had fixed the problem, but obviously, they didn't,' she said this morning.

At 1:16 p.m. yesterday, a power outage occurred across the entire power grid, which services Whitehorse, Faro, Haines Junction, Ross River, Teslin, Carmacks and Mendenhall. Faro was forced to rely on diesel power for seven minutes.

Power was restored to most areas by 2:00, although some parts of the Marwell area had to wait until 2:20.

The wheel's governor or 'companion' part, said Patterson, failed again, which has left Yukon Energy workers scratching their heads. An expert has been called up from BC Hydro to assess the situation here, and to try and pinpoint the cause of the breakdowns.

'People are going through every inch of the system trying to find the problem,' said Patterson. The fourth wheel unit has been taken out of service, 'and won't be put back into work until it's fixed,' she said.

In the meantime, the power grid is running off the remaining three other hydroelectric turbines at the Whitehorse dams, which, when combined, equal the 20 megawatt power of the lost fourth wheel. In the event of a failure from any of these three generators, Whitehorse will still have backup power from the two generators at the Aishihik dam, which can handle 30 megawatts. The peak for summer energy usage is estimated to be between 20 and 35 megawatts, said Patterson.

As this is the second major power outage this August, many residents and businesses are wondering how reliable Whitehorse power really is.

'Consistency is really important for businesses,' said Whitehorse Chamber of Commerce president Rick Karp.

'It's really draining for the employees, the managers, wondering how long is the power going to be out for?' It's confusing.'

He said power outages lose business money because most stores can't complete transactions, and because the power surge can damage electronic equipment, adding repair costs to the mix.

'These power outages can turn out to be very expensive.'

Karp said some businesses rely on backup power, but not every one can afford that.