Power was out for much of St. Thomas early to mid-Wednesday, stretching from about 1 a.m. until nearly 10 a.m. for customers on several feeders, the latest in a string of blackouts tied to limited generation capacity at the Randolph Harley Power Plant.
With power restored by noon, Virgin Islands Water and Power Authority CEO Karl Knight said there was finally some better news: a long-dormant generating unit had been repaired and returned to service, adding 20 megawatts of capacity and giving WAPA what he described as “more than adequate generation” to meet demand.
Knight explained that the recent outages stem from a design flaw in Phase II of the Wartsila power units. The four engines, each rated at nine megawatts, are linked by shared systems. When a compressed air line failed last week, one unit tripped and automatically shut down the others. “They function individually, but there are common systems that tie them together, and in this case one failure took out all four,” Knight said. “That’s something we are now working with Wärtsilä to correct, so they operate completely independent of each other.”
The loss of those units left the utility scrambling to keep up with demand and forced rotational outages across St. Thomas-St. John, that began Sept. 11, when WAPA issued a series of alerts warning that feeders 7B, 8A, 8B, 9C, 6A and others would be cycled off until additional generation came online. Wednesday, WAPA confirmed that Unit 27, one of the older Harley plant generators that had been offline for months due to deferred maintenance, was restored after a rebuild of its fuel pumps and other key components.
“Unit 27 isn’t one of the ones slated for retirement, and getting it back was critical,” Knight said in a call with the Source. “It strengthens our base. With all available units except Unit 23 now online, we have more than adequate capacity.” He added that customers should expect more stability beginning Wednesday evening, though he cautioned that reliability also depends on the success of ongoing maintenance and system upgrades.
WAPA has maintained that the outages in recent weeks were necessary to keep the grid stable, especially during peak hours.
Knight, after a briefing with his team Wednesday, said progress is being made. “We’ve been running really thin on generation, but with this repair, we are in a much better position than we were last week,” he said.