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Matt Wallis

The tidal energy “gold rush” is on, and the Snohomish Public Utility District is the latest prospector to stake its claim to potentially potent sources of power in Puget Sound waters, including Deception Pass and Guemes Channel.

Some of the state’s strongest currents run in the waters of Skagit, Island and San Juan counties, attracting national attention from tidal energy experts as well as regional utilities.

Officials at the Snohomish utility hope to harness tidal power at seven sites in the Puget Sound, including the Sound’s fastest-running currents at Deception Pass, to provide electricity for their growing customer base. At present, the district doesn’t generate its own power, instead buying electricity from the Bonneville Power Administration. Tacoma Power has a permit to study Tacoma Narrows in hopes of installing tidal generators there.

“Right now, it’s kind of a gold rush, and everyone’s like: ‘Let’s go forward,’ and the industry is saying, ‘It’s benign,’” said Keith Kirkendall, a branch chief for NOAA’s National Marine Fisheries Service.

Kirkendall deals with NOAA Fisheries’ reviews of permits filed with the Federal Energy Regulatory Commission that could impact endangered or threatened species, such as the southern resident killer whale or the chinook salmon.

Tidal power, with the potential to provide electricity for roughly 60,000 homes in Western Washington, involves placing dozens of turbines on the bottom of the sea where strong, smooth currents ebb and flow regularly. The currents spin the turbine rotors, which could reach up to 53 feet in diameter, generating electricity in a manner similar to wind turbines. Officials with at least two utilities hope that several of the state’s inlets and channels will prove suitable for tidal turbines.

But tapping the kinetic power of the ocean is an emerging field with developing technology and many unanswered questions, including those about the federal processes to approve building tidal power plants.

Northwestern tribes and fishermen say they are concerned about the turbines’ impact on salmon and crab. Scuba divers want to know what an installation would mean for a favorite recreational spot. Environmentalists worry about the possible effect on endangered whales and other species.

With 1.6 million more residents expected in Western Washington by 2030 and utility companies facing mandatory requirements for renewable power, tidal power is just one of the options the Snohomish utility and other regional power companies are exploring.

The tide of public opinion has turned against hydroelectric, coal and nuclear power, utility officials say. Options for power generation are limited, and utilities are exploring solar, geothermal, wind, manure-produced methane and tidal energy as possible solutions for the region’s growing power demands.

The Snohomish utility, which is one of the Sound’s three biggest power companies, also advocates customer conservation, but with 10,000 new customers each year, utility officials must seek other sources of electricity, said Steve Klein, general manager. Klein also led Tacoma Power’s foray into tidal power when he was with that company.

Whether the utility gets into the business of tidal power will depend on whether turbines can operate in an environmentally sound way, if the technology can be used at the selected sites in the Sound and if it’s economically feasible, Klein said.

The federal energy commission has given the utility three-year permits to study seven potential sites, including Guemes Channel, San Juan Channel and Spieden Channel, also in the San Juan Islands, as well as Admiralty Inlet, where the Sound’s greatest volume of water passes through. The utility district is also looking at Agate and Rich passages.

Work at each site would be conducted in three phases, costing between $2.6 million and $3.1 million. The first phase is under way and is estimated to cost $50,000, making use of a $350,000 study by the California-based Electric Power Research Institute. The institute is a nonprofit group that researches electrical power generation for its member companies, including the Snohomish utility.

“It’s important to us to look in our own backyard,” said Klein about finding power resources.

One of the big attractions of tidal energy is that it is predictable, said Craig Collar, senior manager of energy resources development at the Snohomish utility.

Water is almost 1,000 times more dense than air, which means a tidal turbine spinning far slower than a wind turbine of the same rotor size can generate far more power, said Roger Bedard, a mechanical engineer with the Electric Power Research Institute. He has studied several sites in North America for utility companies interested in tidal energy and is working with the Snohomish and Tacoma utilities.

“These are like little wind machines on steroids,” Bedard said.


Studying the sites

A study of Admiralty Inlet, using acoustic Doppler technology to profile the currents, will begin within a week. First, the sonar will be used to measure the currents on the surface, and then a unit will be submerged for a month to record two 14-day tidal cycles, Collar said.

The equipment then will be moved to Deception Pass to measure those swift-running currents. Scientists at the University of Washington, under contract with the utility, will interpret the data and information compiled from other studies with an eye on installing turbines.

The Snohomish utility selected Admiralty Inlet and Deception Pass to study first because the inlet has the greatest flow of water volume, and the pass, the swiftest-running currents in the Sound. All other sites fall between those two extremes.

In the Sound, seawater must flow through either Deception Pass or Admiralty Inlet, Collar said. All cargo ships destined for the ports of Seattle and Tacoma, or naval aircraft carriers or submarines headed for bases at Everett or Bremerton, must pass through Admiralty Inlet.

Currents at Deception Pass can flow up to 8 knots; a minimum of 4 knots is needed to turn the turbine rotors, Collar said.

While Deception’s currents are strong and consistent, they may prove to be too treacherous for turbines. If the water’s turbulence extends to the seabed, 132 feet at its deepest point, the turbines won’t work at that site, Bedard said.

“We don’t know if that turbulent flow extends throughout the water column,” Bedard said.

The studies of the first two sites will help Snohomish utility officials make decisions about whether to study the other five sites, Collar said. If the utility decides to test turbines, the information will also help tidal power experts select custom-built turbine designs suitable for the various sites, Collar said.

How many turbines, their size and where they will go will depend on where the technology is at when and if the utility gets to the point of testing turbines or installing a tidal power plant in the Sound, Collar said.

Estimates of between 450 and 560 turbines at Admiralty Inlet and 116 in the San Juan Channel were filed with the utility’s federal permit applications. Those estimates could be “way off,” Collar said.

At some sites, the technological innovations made to the turbines may have to catch up with the dream of harnessing the sea’s energy.

The San Juan Channel, with an average depth of 208 feet, would be pushing the limits of the technology, Collar said.

The Spieden Channel, with an average depth of 273 feet, would require engineers to develop technology that companies could afford to install and maintain, according to the utility’s 2006 proposal to federal regulators.


Environmental concerns

Whales and submarines would have to weave around the turbines, possibly as many as 560 in Admiralty Inlet, that would be installed in groups offset from each other.

“That’s quite an array for a gray whale to hit,” Kirkendall said.

The endangered California gray whales spend late spring eating microscopic crustaceans between Camano and Whidbey islands. Whale experts say that the loss of a few southern resident orcas, which number about 85 and have a handful of births each year, could be devastating to the population.

“We want to be a responsible utility, and we want to represent the interest of the public,” Klein said. “I think there’s a pretty strong environmental stewardship in the Puget Sound area. Conservation is something we really believe in.”

It’s impossible to protect fish or whales with a screen or cage around the turbines. First, kelp would quickly block such a barricade. Second, Collar said it would interfere with the currents.

Klein said he thinks selecting where the turbines are installed may mitigate some of the environmental concerns. For example, the turbines could be installed outside the historical paths of migrating whales.

“These things do not spin at the same speed as a wind turbine,” Klein said. “Most species that can be observed can avoid them.”

The Samish Indian Nation and Swinomish Tribe, as well as at least eight others in the region, are keeping an eye on the federal permitting process for both Tacoma Power and the Snohomish utility.

Although the Samish Tribe supports green power, tribal leaders are cautious when it comes to emerging technology that could have unknown effects on the oceans, said Christine Woodward, director of natural resources for the Samish Indian Nation.

“A major concern for us is a health of the marine system,” Woodward said.

One thing the utility district’s engineers and NOAA officials seem to agree upon is that the exact affect on the environment won’t be known until turbines are put in the water. That’s why many eyes will be on Ireland, where the world’s first large tidal power plant will be installed in August.

“(The industry) knows if a right whale rolls up the beach, they know it’s just going to devastate them,” said Kirkendall of NOAA fisheries. “They know if they have that kind of bad PR, it could cripple them.”


Gobbling up tidal sites

One of the hot spots in the tidal gold rush is Strangford Lough in northeastern Ireland, where a 1.2-megawatt turbine will be installed in August, making it the world’s first large-scale prototype of tidal power. Snohomish utility officials will travel to Ireland this summer to visit the site.

The Strangford installation will power 1,000 homes, and its potential effect on the environment will be closely monitored by scientists who have tagged seals and sharks with radio transmitters.

In North America, there are only two tidal sites that are hooked up and providing power. One is at Race Rocks Marine Protected Area in British Columbia. The other is a six-turbine test site in the East River in New York.

Still, utility companies in the United States are lining up in hopes of getting in on the tidal game. The Federal Energy Regulatory Commission, the agency responsible for permitting tidal power plants, has issued 58 permits to study locations from Anchorage, Alaska, to Key Largo, Fla. Another 30 applications are pending.

Roughly 90 percent of the United States’ tidal resources are in Alaska, Bedard said. Permits have been granted to study some of the strongest currents in the world, including in Cook Inlet, Resurrection Bay and the Wrangell Narrows, all in Alaska.

Sites of interest in the Northwest include the mouth of the Columbia River, where an Oregon utility “gobbles up” miles of estuary that aren’t in the shipping lane and are deeper than 35 feet, said Kirkendall of NOAA fisheries.

“Any sport fisherman out there with a downrigger is going to be out catching that thing,” said Kirkendall of any potential turbine installations in the river.

Already, political players from both sides of the aisle have begun to support the tidal industry. U.S. Rep. Jay Inslee, D-Wash., has introduced a bill to spend $50 million each year for 10 years on ocean-energy research and to make low-interest loans available to develop renewable energy from the ocean. U.S. Sen. Orrin Hatch, R-Utah, has sent letters to NOAA Fisheries. Hatch’s home state is the base of one of the tidal equipment manufacturers.

Since the technology is still in its infancy, everyone — including the energy commission — is venturing into unexplored waters.

In February, the commission changed its rules regarding permits to study tidal sites to require that applicants show progress and meet deadlines, said Celeste Miller, an energy commission spokeswoman. If they don’t, the commission can yank their permit, she said.

“The reason we instituted these policies is to prevent large pieces of the ocean from being locked up and not being able to be developed,” Miller said.

Additionally, the agency is looking at its process for licensing applicants.

Because the sites are in critical habitat areas for the southern resident orca and the chinook salmon, NOAA Fisheries is among several agencies that are required to sign off on any turbine installation.

But Kirkendall of NOAA said the way the energy commission’s permits are written, it appears that test turbines could be installed without seeking an additional permit. Kirkendall said he’s concerned that utility officials would not want to stop after the test stage, even if it resulted in an adverse affect on salmon or marine mammals.

“When a pilot study costs $1 million or $2 million, do you really think they want to pull them out?” Kirkendall asked rhetorically.


‘Little tornadoes’

At Deception Pass, the intensity of the currents can be clearly seen from the 72-year-old bridge that arches over the seawater. It is a favorite route of the Victoria Clipper as it travels from Seattle to Victoria, B.C. Closer to the water, white swirls rush against the rugged slopes of Deception Pass State Park’s shoreline.

It’s possible that the Snohomish utility would install an underground cable to a small substation, which wouldn’t need to be built in the park, the utility’s Collar said. While the federal permit says four turbines could be installed, Collar said it is possible it could be as many as a couple dozen.

But, he said, he doesn’t know. It all depends on the technology that is developed over the next few years and what the acoustic Doppler sonar testing shows.

The narrow pass with its densely forested, steep rocky slopes that once challenged New Deal work crews could prove a tough place for modern-day engineers to work, he said.

“The water is just rushing through,” Collar said.

The swift currents of Deception Pass could generate enough electricity to power 2,000-plus homes, provided the waters aren’t too turbulent. But if eddies swirling on the surface of the blue-green waters prove to run as deep as the 132-foot channel, they could sink a proposal to tap the pass’s tidal energy before it has even begun.

“They are like little tornadoes moving through the pass,” said Bedard of the Electric Power Research Institute.

* Marta Murvosh can be reached at 360-416-2149 or .