Utility needs to boost line capacity out of power plant for future needs

Wrangell's generating plant has an eight-megawatt line out the door but needs to go up to 12 megawatts if it wants to fully serve the power needs of the community during shortages, according to the head of the utility department.

This need, while known for a couple of years, was starkly illuminated by two back-to-back events, said Superintendent Rod Rhoades at Wrangell Municipal Light & Power. The first was a Nov. 30 windstorm that severed the Southeast Alaska Power Agency's feeder lines in town, followed by a cold snap this month.

"We were seeing, regularly, the (power) demand of the community above 9.5 megawatts," Rhoades said Friday. "If those lines, SEAPA's lines, had been severed during the cold snap, we would not have been able to supply enough power to keep the community all lit all at once. It's the result of two events right on the heels of one another. The unthinkable happened, therefore we need to be more aggressive about addressing this possibility."

Borough Manager Jeff Good raised the concern at the borough assembly's Jan. 11 meeting.

When temperatures are at or above 40 degrees, the utility sees a draw of 6.5 megawatts, Good told the assembly. When temperatures drop, like they did earlier this month, Wrangell's power needs go up to 9.5 megawatts. With two of the utility's five generators down (Generator 1 was getting maintenance, Generator 5 is being repaired), Wrangell itself can generate 6 megawatts.

That's a problem.

"If we lose SEAPA right now, we are short on power," Good said.

SEAPA, which operates the Tyee Lake hydroelectric project, provided Wrangell and Petersburg a peak load of 23 megawatts during the cold snap.

"Anything above 21, our guys were going on standby. We'd start up the generator. We alternated with Petersburg. We were two days on, they were two days on, just to make sure we met the loading. That's where we are at. During the cold temperatures we ran the generator for 14 hours to supplement SEAPA," Good said.

As of Monday, Generator 1 had been brought back to service. Once Generator 5 is returned to the lineup, all five generators could provide 11 megawatts of power. The problem is the utility facility's internal wiring was designed for eight megawatts and can't support the generators' potential output.

"Down the road, we need to develop the overall cost to get the internal wiring to match what we can actually produce and what the demands are of the city," Good told the assembly.

Rhoades said the utility will have to replace the two-megawatt transformers in Municipal Power & Light's distribution system. There are four transformers. One was upgraded last July to a $50,000 three-megawatt transformer, but the remaining three units need to be swapped out, still, which will take Municipal Light & Power to 12 megawatts, Rhoades said.

To upgrade the remaining ones may cost well north of $150,000, estimated the superintendent, due to rising costs in the increasingly volatile supply chain.

"The cost of copper is fluctuating almost daily," Rhoades said. "About six months ago, we bought a ... (0.1 megawatt) transformer for $30,000. We just had to quote another one and the price doubled. The delivery time went from six weeks to 50 weeks. These are real impacts to us. They all come together to paint a financial narrative that I don't have enough visibility on yet," Rhoades said.

The utility is an enterprise fund, meaning electrical rates charged to customers are supposed to cover operating costs, though other municipal funds can be directed to improvement projects.

Good said he spoke with Petersburg's borough manager about entering into a mutual aid agreement to have something in place, from a financial standpoint, "if we needed assistance from each other."

The borough's next steps to meet capacity needs are to develop the scope of work, with Rhoades, Mark Armstrong, electrical line supervisor at the utility, and Capital Facilities Director Amber Al-Haddad, getting together to nail down the cost, Good said. But it won't be before this winter is over with.

"The goal is to have everything developed by late spring, then bring it before the assembly with the cost to give them an overall scope of work," Good said.


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