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Wind power comes into its own in Alaska Kodiak Pillar Mountain project adds wind to hydro; contractor STG says foundation work costly part of remote wind projects Kristen Nelson Petroleum News
Alaska had hundreds of small wind turbines in the 1980s because of the oil crisis and federal incentives for renewable energy, but “the technology was relatively immature and was not adapted to Alaska’s extreme climatic and geographic conditions.”
As a result, Alaska Village Electric Cooperative President and CEO Meera Kohler said, most of those 1980s wind projects were offline within a year — many, in fact, never started up.
But the technology matured, she told the second annual “Business of Clean Energy in Alaska” conference in Anchorage June 18, and in the 1990s Kotzebue decided it was time to try the technology again.
When the Kotzebue wind farm started up in the late 1990s they were saving tens of thousands of gallons of diesel fuel, she said, and they now have more than a dozen machines running.
“They really have pioneered where we go in rural Alaska with wind energy,” she said.
Since the initial Kotzebue installation, 21 more communities have installed wind systems, with many more on the drawing board, Kohler said.
Systems combining wind and diesel power are replacing diesel systems “at a fairly rapid pace,” she said, as the price of diesel fuel has risen to become almost unaffordable at the same time that it is become less environmentally acceptable.
Wind plus hydro Ron Acarregui, vice chairman of Kodiak Electric Association, talked about one of the state’s newest wind installations, KEA’s 4.5-megawatt wind project on Pillar Mountain, which was completed in July 2009.
Eighty percent of KEA’s electricity is generated by hydro at Terror Lake, Acarregui said.
Before Pillar Mountain started up, 20 percent of the utility’s power came from diesel but wind power now generates almost 9 percent of the utility’s power.
Acarregui said Kodiak’s large electric users are fish processing plants, the satellite launch facility and the Coast Guard base, the largest in the United States. Between the three, especially if there are launches going on or the cutters are in at the Coast Guard base, “the demands can be very high and we can have some pretty drastic spikes.”
Kodiak is a standalone grid, he said, and KEA does its own power generation, transportation and distribution.
The utility’s vision statement is to produce 95 percent of its energy sales from cost-effective renewable power by 2020.
“Currently we’re about 88 to 89 percent renewables thanks to the addition of our wind,” he said.
In addition to wind, KEA is looking at the potential of tidal, wave action and solar power and at the potential for electric cars on the island, which has only 40 miles of paved roads.
Terror Lake storage Acarregui said the utility’s goals with wind power were to lower fuel costs, lower emissions, reduce power cost volatility and use Terror Lake as a storage battery.
“The project has worked very well because when we have our wind on and we don’t have to use the water then that gives us additional potential for hydro and we don’t deplete the storage area,” he said.
Current savings are 830,000 gallons of fuel, a savings of more than $2.2 million at a $3 a gallon diesel price.
Each of the foundations for the three wind towers required 300 yards of concrete with 30 tons of rebar.
Overhead and underground lines were required, as was road work because of the requirement of getting the turbines into place.
The Pillow Mountain site is above the harbor and the turbines had to come through town, requiring removal of poles and light fixtures because of size of the pieces being moved.
“The community turned out and watched — it was like a big parade — and watched all of these work their way up the mountain,” he said.
The wind turbines came in on a barge and the transportation cost per unit was “tremendous,” Acarregui said.
The towers came in three sections, along with the blades and nacelle; assembly required a 440-ton crane which was brought in from Wyoming in boxcars and reassembled.
Three 1.5-megawatt wind towers were installed.
The blade length is 122 feet and startup speed is 8 miles per hour, with shutdown at 55 mph.
What does this mean for KEA rates? While residential rates in the United States have increased steadily since 2000 — a total increase of 41.75 percent — KEA’s rates have decreased by 4.75 percent.
And for the future, additional turbines are planned at Terror Lake, which has two 10-megawatt turbines now, and then three more wind turbines.
Focus on foundations Jim St. George, owner and founder of STG Inc., has been involved in heavy construction projects across Alaska for more than 30 years.
STG does infrastructure all over the state, St. George told the Clean Energy conference. Discussing costs on a typical wind project, he said “a large percentage of the cost goes into turbine procurement and things that are really out of our control.”
When it comes to wind projects, he said STG believes it’s “more about foundations and infrastructure interties” which account for about 90 percent of the work. The turbine install, the actually raising of the wind turbine, is a small percentage of the work, St. George said.
But of course what you see is pictures of the turbine being raised into place.
“People don’t want to look at pictures of guys digging holes in the ground and tying rebar — but the reality is that’s a huge part of that,” he said.
Illustrating with time lapse photography of one project, St. George said you see roads being built, and foundations being dug and eventually toward the end there’s a crane on site and then the turbine install right at the end.
Costs variable Costs vary due to the machine installed, but also are based on a lot of other circumstances, he said, such as transportation.
“Keep in mind, there’s no roads anywhere we work — it’s all barge or it’s airplane supported.”
If other infrastructure is being built at the same time, some of the cost can be spread, he said.
STG can’t control costs such as turbine procurement and interconnect costs. St. George said STG feels it has some control over about 45 percent of the project cost.
And the biggest part of what the company has some control over is the foundation.
On different projects the foundations are controlled by ground conditions, which vary from permafrost to bog to unconsolidated overburden, he said.
There are a whole range of different foundations, St. George said, and foundations have evolved over time.
While costs vary with foundation conditions, in general foundation costs have been driven down about 50 percent over time, he said.
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