Cook Inlet slated to have one of the first tidal power generators in the country

Low tide at Kenai Beach. (Sabine Poux/KDLL)

Cook Inlet has long been a hotbed of oil and gas development in Alaska. But for years, renewable energy advocates have been eyeing another Cook Inlet resource — tides. The inlet has some of the largest tides in the world but their energy potential has remained untapped.

One company is trying to change that, and says it could have a generator in the water in the next three years.

Ocean Renewable Power Company, of Maine, is filing a permit later this spring for a pilot project in Nikiski. Merrick Jackinsky is one of two employees in Anchorage.

“Where we’re looking at, the East Foreland site, is mainly just because the extreme velocity that it has there to kind of get that bigger bang for our buck right off the bat,” he said.

Anyone who’s fished in the area knows the tides can really rip. That’s important because the company’s tidal tech relies on the movement of the tides to spin turbines connected to an underwater generator.

The turbines work when the tide is going in and out.

“So we’re always able to generate power, except during slack tide,” Jackinsky said.

ORPC currently has another hydrokinetic generator in Igiugig, on the Alaska Peninsula. That device sits in freshwater, in the Kvichak River, and is helping Igiugig ween off its dependence from diesel.

The potential power in Cook Inlet’s tides is much more vast. Studies estimate the inlet holds over a third of all tidal energy potential in the U.S.

But that power has proven elusive. Multiple companies, including ORPC, have filed permits with the federal government that haven’t come to fruition.

One challenge has been finding a market.

“Tidal power’s biggest concern right now, I’d say, is solar and wind power,” said Chris Rose. He’s executive director of Renewable Energy Alaska Project, a non-profit that advocates for renewable energy statewide. ORPC is a member.

“Solar and wind power have come down so quickly in price over the last decade,” Rose said. “It used to be that tidal power 20 years ago was competing against fossil fuels. But now, really, the biggest competitor is solar and wind. And so more investment has gone into those renewable technologies and less has gone into tidal.”

The Cook Inlet project would be one of the first tidal power generators in the country. Jackinsky estimates tidal is 10 years behind its wind and solar counterparts.

Tidal energy, however, could be more dependable than solar and wind. It’s predictable hundreds of years in advance.

“If you were to put tidal power stations up and down Cook Inlet, they would produce power at different times of the day,” Rose said. “Which could make the resource what the utilities call a ‘base load resource’ — something that they can manipulate and count on.”

Initially, the company hopes to produce a megawatt of power from the device, eventually increasing that load into the hundreds of megawatts. The Railbelt as a whole has an average annual load of 600 megawatts, according to REAP.

But that’s all far down the road. First, ORPC has to file a preliminary permit with the federal government, including an environmental assessment. Any project in Cook Inlet has to avoid damage to the fish and whales that call the region home.

Jackinsky said salmon have been able to avoid the turbine in Igiugig because the device is free floating and doesn’t dam up the water.

In three years, he said, ORPC could have a pilot device in the water. That first device wouldn’t send power to the grid , but would be in place as a sort of test — to gauge the impact of the salty water on the machine, for example. A permanent device could take a decade.

“It’s more like a marathon, it’s not like a sprint,” he said.

As for the all-important market, ORPC thinks it has one. The company signed a joint development agreement with Homer Electric Association, the local utility, and HEA said it will purchase power generated by ORPC for its grid.

Currently, HEA gets most of its power from natural gas also produced in Cook Inlet. The oil and gas industry in Cook Inlet has slowed in recent years, with lackluster industry interest in offshore exploration and a declining supply of natural gas that shuttered the once-bustling Kenai liquefied natural gas plant.

Renewable advocates like Rose see tidal as a more enduring resource.

“When you invest in the technology like that, you’re investing in perpetuity,” he said.

He said with tides like the ones in Cook Inlet, Alaska could be at the center of tidal energy production.

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