Rolling blackouts continued on St. Thomas all day Thursday as the V.I. Water and Power Authority dealt with system-wide difficulties stemming from a surge created when a vehicle collided with a utility pole in Frenchman’s Bay Wednesday morning shortly after midnight.
"It has spiraled into other issues," WAPA spokeswoman Lynette Moreland said, when asked Thursday evening why rotating power outages continued more than 24 hours after a single utility pole was damaged. The precise causes are very technical, but the surge that occurred at the time of the accident caused feedback, which cause the feeder to go out, which then triggered the rotating outages, she said.
Moreland referred technical details to WAPA Chief Operating Officer Greg Rhymer, who could not be reached for comment. As to when things might return to normal, "hopefully it will end today," Moreland said.
While the details of this particular situation remain unclear at present, the pattern appears similar to that of rolling blackouts St. Thomas experienced in April and May and also last fall.
At a governing board meeting last October, WAPA Executive Director Hugo Hodge Jr. said a spate of rolling outages in the preceding weeks came about because the plant’s biggest generator was out of service, leaving a very small margin of power production. Without it, the rest of the system, which also needs more preventive maintenance, can only supply the full peak demand if nothing else goes wrong, Hodge said.
When there have been problems with other units, the distribution system has automatically triggered rotating power outages in order to prevent a longer, island-wide outage, Hodge said at the time. WAPA has not confirmed the same thing is happening now, and the current situation may have entirely different causes. But Hodge’s description from last October appears very similar to Moreland’s explanation Thursday evening.
A string of outages prior to Good Friday this year were also triggered by a generator being down at the wrong time. At a May board meeting, Hodge said one generator tripped offline just as WAPA was taking another offline, triggering rolling outages to protect the whole system from going down. Parts of the grid became unstable under unusual circumstances, where equipment was not behaving as expected, Hodge said at the time.
In both those prior spates of outages, Hodge pointed to overhauling and bringing more units back online as the way to stabilize the system. A similar dynamic may be occurring currently, although in the absence of confirmation from WAPA, that remains unclear at present.