The Liberty Consulting interim report on the state of this province’s electrical system should be a sharp wake-up call for Nalcor and Newfoundland Hydro, as if they needed one.
The report questions Newfoundland Hydro’s commitment and ability to maintain the province’s electrical grid, and cites a series of places where the utility fails to meet the standards other utilities hold.
This editorial looks at just one small piece of that maintenance problem — the cause of the major blackout following a transformer failure at the Sunnyside terminal on Jan. 4.
The Liberty Consulting report goes into great detail about what caused that blackout, but one of the first things the consultants point out is that, “The transformer failure, however, should have had only a minimal and limited effect on customer numbers interrupted and the length of those interruptions.”
So why did it end up being a cascading series of problems? Well, there are reasons why, and those reasons don’t make Hydro look very good.
The first problem is that the transformer had been showing signs of being on the verge of failure: an early warning sign for transformer failure is higher than normal levels of acetylene in the transformer oil, because of arcing. The Sunnyside transformer “had a history of elevated acetylene gas for many years prior to the events of early January 2014.”
In September 2013, oil sampling had shown a dramatic increase in acetylene, and a laboratory report at that time suggested more frequent testing.
That testing wasn’t done, because Hydro officials decided the acetylene was coming from somewhere else in the transformer, even though it did no analysis to see if its decision was based on evidence. Not only did it not investigate, it actually cancelled work: “Hydro also deferred scheduled preventive maintenance and testing on this transformer. Such testing might have identified abnormal internal conditions,” the report says.
But that was only the first problem: when the transformer had trouble, a circuit breaker should have disconnected it. But the breaker also failed to work properly.
“The B1L03 breaker was overdue for its scheduled six-year maintenance. Hydro last serviced and tested it in June 2007. … (Had) Hydro serviced and tested the B1L03 breaker within the six-year time limit (June 2013), that breaker likely would have functioned properly.”
Hydro already knew that circuit breakers had to be regularly tested and “exercised”; that was one of things it discovered after a major power failure in January 2013.
The breaker failure could have been avoided if the company had invested in a breaker failure protection system; it had done so in other places, but not at Sunnyside.
“Hydro had determined, sometime in the past that the risk of a 230kV breaker malfunction’s occurring at the same time as a transformer fault presented too low a risk to justify the expense of installing a 230kV breaker failure scheme to mitigate such risk,” the Liberty report says.
So, Hydro had evidence the transformer was showing signs of problems and did nothing — Strike 1.
Hydro failed to follow its own advice on circuit breaker maintenance, even after circuit breaker failures had caused another major power failure — Strike 2.
Hydro didn’t have breaker failure relay protection in place because of cost — something the consultants say the system requires — Strike 3.
Three strikes — so, who’s out, besides the power for 187,500 customers?
Former premier Kathy Dunderdale was fond of touting Nalcor’s “world-class” experts. There’s nothing world class about this situation.