Enthusiasm swells for Cook Inlet tidal project after summer study
After studying the tides near Nikiski this summer, researchers said they’ve confirmed it would be a world-class place to put a tidal power generator.
And they said the measurements they took will help them develop technology that can withstand the harsh conditions of Cook Inlet’s tides — some of the largest in the world.
Levi Kilcher, from Homer, was part of a team from the National Renewable Energy Laboratory that measured the velocity and turbulence of the tides at the East Foreland, in Nikiski. He said at a virtual presentation Wednesday the results are very promising.
“What we see is we see really strong currents at this site," he said.
Renewable energy advocates have been talking about turning Cook Inlet’s tides into energy for a while.
This spring, a Maine-based company filed a preliminary permit to start exploring the resource. Ocean Renewable Power Company said it hopes to have a generator in the water at the East Foreland in the next several years.
One variable researchersmeasured this summer was the velocity of the tides.
Velocity, Kilcher said, tells them how much power can be generated. The stronger the current, the greater the potential to generate power.
“Just in this little section of Cook Inlet there’s the potential for like 100 megawatts or so," he said.
Kilcher said that shows the site is the right size for a project like ORPC’s. The company said it hopes to build its project up to 100 megawatts. That’s about a sixth of the Railbelt’s entire annual energy load.
Another key piece is tidal turbulence, to make sure the technology can withstand the harsh push and pull of the water.
“What they learned in the early days of the wind industry is that turbulence rattled the wind turbines and caused them to break and fail," Kilcher said. "And so designing devices robust enough to handle the turbulent conditions is really important.”
Kilcher said they’re still in the process of analyzing the turbulence they measured at the East Foreland site. He said he hopes the raw data and analysis will be out next year.
The technology ORPC plans to put in the water relies on the movement of the tides to spin turbines. Those turbines would then be connected to an underwater generator and would generate power while the tides are moving in and out.
ORPC already has a generator in the Kvichak River, in Igiugig. Another company installed turbines in New York’s East River.
But the technology is still on the newer side, especially for saltwater. And it’s not yet produced to scale, like wind and solar technology, which makes it more expensive than its renewable counterparts.
Kilcher said he thinks the next step in tidal development is scaling up the technology to drive costs down.
“And I think, as a former Alaskan and an Alaskan in my heart, that Cook Inlet would be a great place to demonstrate some of these technologies as they’re starting to scale up," he said.
Historically, finding a market has been a challenge for power production companies. Multiple companies, including ORPC, have filed permits for power projects with the federal government that haven’t come to fruition.
But Homer Electric Association is on board with ORPC’s current project. The co-op said it will purchase the power ORPC generates.
David Thomas leads the team at HEA that’s looking at ways to get the utility to 50 percent renewable energy. Currently, the vast majority of the utility’s power comes from natural gas generated in Cook Inlet — not far from where ORPC plans to put the generator.
He said proximity to existing structures is important for making new power projects affordable. That's promising for the East Foreland site.
“Which is adjacent to the highway system and adjacent to our existing transmission lines," Thomas said. "And where those things — the resource, the transmission, the road infrastructure — come together is where you can make a project happen that otherwise might not pencil out.”
ORPC hopes to have a pilot device in the water in the next three years, with plans for a permanent device taking closer to ten.
There’s at least one other company that is looking into developing a tidal resource in the inlet. That site would be closer to Anchorage.