From the Sterling Highway, it is nearly impossible to hear the low hum of the Homer Electric Association’s combustion turbine plant over the steady roar of highway traffic just north of Soldotna.
But, with each step closer to the building that houses the 63,000-horsepower turbine, the noise increases to the point that even shouting become inaudible; the sound of traffic fades and the powerful roar accompanied by a teeth-chattering rumble of the company’s newest power generation facility becomes unmistakable.
For several hours Wednesday, staff from HEA took community members on tours of its new backup facility.
When the plant was brought online on March 30, it became the latest in a series of backups built into the HEA’s system — designed to fill in when the company’s main generation plant in Nikiski goes down.
Since Jan. 1, 2014 when the company began generating its own power, it has primarily used the Nikiski Combined Cycle Plant — which features steam and natural gas turbines that can produce a total of 80 megawatts of power at a time — and a percentage of the state’s Bradley Lake Hydroelectric project — a plant whose power generation is shared by six state utilities — to power the Kenai Peninsula.
But, sometimes the company’s primary power sources cannot keep up with the demand.
“We have planned outages and we have unplanned outages,” said HEA Director of Power, Fuels and Dispatch Harvey Ambrose. “Yet you always have to have the lights on. I don’t think the people on the peninsula would be too happy if we said, ‘You know, we’ve got to take a six-week outage, no electricity for six weeks.’ Our demand is identical whether Nikiski is running or not.”
To deal with the potential disruption in service, HEA uses the Soldotna-based power plant and the Bernice Lake power plant in North Kenai, to contribute megawatts when necessary.
One of the first tours of the morning, led by HEA power plant superintendent Jim Kingrey, included more than a dozen students from Kenai Central High School. While the students wore identical green hard hats and yellow ear plugs for protection from falling debris and noise, many had foregone jackets and warm weather gear and stood shivering in the shadow of the warehouse-style building where the offices and operating room are housed.
While they were mostly silent as Kingrey spoke outside, when the group moved inside, the plentiful heat coaxed communication out of several of them.
As Kingrey explained how the facility operated, they asked questions about how power was generated, how the facility was operated and where the power was stored.
“I expected it to be a lot simpler,” said KCHS junior Caleb Rohn. “I didn’t realize so much went into running the turbine. I thought the gas went in and spun the turbine and that was it.”
Rohn, who said his dad works at a refinery in Nikiski, said he wanted to study mechanical and electrical engineering. He said he was surprised by some of the things he heard while on the tour.
“I thought it would be a lot more expensive (to operate), but (Kingrey) said it’s just $1-$1.5 million a year.”
As the students filed into the operation center of the plant, a bank of computer screens displayed the complexity of the operation — but no one was nearby to monitor the displays.
The Soldotna power generation plan can be, and is typically, remotely operated from HEA’s Nikiski facility.
“It’s not cost effective to staff this plant 24/7 because it’s not necessary,” Ambrose said. “This is a simple-cycle plant … so it can be more reliably operated up and down from the Nikiski dispatch center.”
Each of the power sources HEA owns can be operated from Nikiski, he said. So, an operator is always on staff in Nikiski, monitoring the company’s electrical grid.
“Whatever the system demand is, we look at it in advance with what we think it’s going to be and then, we true it up as time gets closer. We’re looking at weather and historical load and all that and we predict what it’s going to be a day in advance,” he said. “We plan to match exactly the output of the units to the demand of the system. You cannot produce more power than you use and you cannot produce less power than you use and you always match.”
After the tour, Ambrose said the company’s quest to provide energy to the Kenai Peninsula — a project dubbed “Independent Light” that took a major step forward when it began producing its own energy in January — had sometimes resulted in frequent outages.
He characterized the outages as growing pains.
“Part of what we were doing with ‘Independent Light’ was making the system as reliable as possible and in the process of meeting that goal, we had to segment the system in ways that made us more fragile. But, we’re close to done and the system will be the most robust that it can be. We appreciate the patience of our members.”
Rashah McChesney can be reached at email@example.com.
If you go: HEA is hosting a series of community meetings peninsula-wide to discuss projects the electric cooperative is undertaking. The next one is at noon today at the Nikiski Community Recreation Center followed by an Oct. 13 noon meeting at the Port Graham Community Center