Standing on a bridge high above the rushing emerald waters at Deception Pass, a narrow strait in Washington's Puget Sound, Craig Collar voices a sense of wonder.

"Just think about the power there," he says. With flows of up to eight knots (or a bit more than nine miles per hour) the site has "definitely the highest currents in the Sound."

Could this powerful tide someday light up homes? Collar, the senior manager of energy-resource development for the Snohomish Public Utility District, will spend the next several years finding out. Following passage of a statewide ballot initiative last year, Washington's big utilities were required to beef up their renewable energy sources - not including traditional hydropower. Collar believes that underwater turbines turned by tides at Deception Pass and elsewhere in the Sound can one day provide electricity for up to 60,000 homes. And the Snohomish utility is hardly alone in testing the waters: Up and down the coast, utilities and private developers worried about climate change and oil dependency are putting money into this newest source of power - the Pacific Ocean.

Ocean power in the West is only in the preliminary stages - there are currently no devices in the water on the West Coast - but already environmentalists, fishermen and even divers are gearing up for a battle. Some observers hark back to the West's one-time embrace of dams. "We heard very similar comments about hydro-power decades ago - it's cheap, clean, all those nice catchphrases. We're living with the results, good and bad," says Clint Muns, director of resource management for the Puget Sound Anglers State Board.

Local environmentalists are concerned about possible impacts to fish as well as to scenery. Deception Pass is not only one of the most-visited state parks in Washington, but also an "outstanding natural area that has every salmon from the Snohomish and Skagit (running) through it," says Steve Erickson of the Whidbey Island Environmental Action Network. "This is not a place to experiment."

Erickson's group would like to see extensive study and slow implementation of the new technology, noting the mass raptor deaths caused by the large-scale introduction of wind turbines at Altamont Pass in California in the 1980s. In the San Juan Islands, ocean machines have been jokingly referred to as "orca blenders," says Amy Trainer, staff attorney with Friends of the San Juans. Her group is concerned about the potential development of two sites in Puget Sound, citing impacts on the fish, the views and navigation. "It's a tricky position for everybody," she says, "because we obviously want alternative energy, but it has to be done responsibly."

The potential of ocean energy is vast, but the technology is mostly unproven. Water is roughly 800 times denser than air, meaning it can pack tremendous energy. With the ocean's energy, the U.S. could potentially generate enough power to meet 10 percent of current national electricity demand, according to Roger Bedard of the Electric Power Research Institute, a nonprofit that is leading the research in the field.

Applications for preliminary study permits have soared. The Federal Energy Regulatory Commission, or FERC, the lead agency overseeing the nascent industry, received 43 filings for preliminary marine-energy permits last year, versus 16 in the previous two years combined. More than half are for sites in the Pacific.

Ocean power isn't cheap. The first projects near San Francisco's Golden Gate could produce power for 5 to 16 cents per kilowatt-hour, which is as much as three times pricier than wind and four times more costly than coal, according to the Electric Power Research Institute. But prices should come down as the technology improves. The federal government - which currently does not fund ocean-power research - may also start chipping in. Rep. Jay Inslee, a Democrat from Washington, is pushing a bill that would provide $50 million annually for 10 years for ocean-power research, plus tax credits.

Ocean energy breaks down into two main categories - tidal and wave. The West has both in abundance. Tidal power, the type being considered for Deception Pass and seven other sites around the Sound, harnesses the ocean's twice-daily ebbs and flows using underwater turbines, which are similar to wind turbines. The best sites have plenty of fast-moving water and not too much eddying (the latter could derail Deception Pass).

Large tidal stations have been operating in France and Canada for decades. Those stations resemble dams with sluice gates, whereas Deception Pass and other small modern sites would hide the turbines underwater.

The only tidal station now operating in the United States is a small experiment in New York's East River, where six grid-connected underwater turbines have been in place since April. The country's most promising tidal sites include San Francisco Bay (under the Golden Gate), Alaska's Cook Inlet, the Western Passage in Maine and Admiralty Inlet in Puget Sound.

Wave energy, which harnesses the up-and-down motion of water to turn electric generators, has far more potential than tidal. The number of good tidal sites is finite, but waves are virtually unlimited. Here again, the West scores highly. The global winds blow from West to East, sending powerful waves crashing against the Western shoreline. "The same machine will collect three times more energy on the West Coast than East," says Bedard.

Wave devices are generally stationed a few miles offshore, since the waves' energy declines markedly at depths of 40 meters or less, according to George Hagerman, an ocean-energy expert at Virginia Tech. Transmitting the energy to shore is therefore a challenge. There are many competing types of wave technology, from buoys to floating "sea snakes," 120 meters long. A big wave farm, the first in the world, is expected to open off the coast of Portugal later this year.

Within the West, Alaska has by far the strongest potential for both tidal and wave power, says Bedard. But the state has relatively few consumers of energy, and it's difficult to transmit its power to the Lower 48 - or even to places in Alaska.

That leaves Oregon and Northern California as particularly promising for wave development. Washington has great waves, but the Olympic Peninsula blocks transmission to Seattle. (Despite this, an Irish company called Finavera is pursuing a pilot project in Makah Bay at the tip of the Olympic Peninsula.)

Southern California has two obstacles: the coastline's sudden eastward tilt, which blocks some waves, and the Channel Islands. "To get big waves for Southern California, you have to go out 20 miles," says Bedard.

Both Oregon and California have plenty of electricity-hungry towns clustered along the coast, with a good grid structure already in place. Oregon's substations have surplus capacity because of the closure of energy-intensive timber plants, notes Kevin Banister of Finavera, which is exploring a few sites in the state. Oregon also is host to a leading wave research center at Oregon State University.

Chevron recently filed for a permit to spend up to $2 million exploring wave energy off California's Fort Bragg. Ocean Power Technologies aims to open a big wave park off the coast of Reedsport, Ore. Eventually, the company hopes to deploy 200 "PowerBuoys," producing at least 50 megawatts and taking up about 1.25 square miles of ocean.

Crabbers are lining up against Ocean Power Technologies' project, saying it would occupy prime fishing grounds above sandy bottoms where crabs like to burrow.

"We're very concerned," says Hugh Link of the Oregon Dungeness Crab Commission, which represents over 400 permitted crabbing boats. "You put 200 of them out there and it will take a significant amount of traditional fishing ground."

Puget Sound's prospective tidal sites are also popular with divers. Riding the current is "like flying," explains Mike Racine of the Washington SCUBA Alliance, an experience that could be rudely interrupted by big underwater turbines. However, he adds, "It's not a simple situation. Renewable energy sources are important and merit-worthy." He plans to lobby for new dive sites as compensation for any lost spots.

Daryl Williams, an environmental liaison for the Tulalip Tribes of Washington, says he too is tracking all the projects in Puget Sound, because the tribes fish in those areas.

The large number of stakeholders, including tribes, fishermen and recreational users, adds to the complexity of a regulatory process that is still adapting to a brand-new industry. Although getting a preliminary study permit has been easy, the process for obtaining a full marine-energy license from FERC is "the same as building the Hoover dam," says Bedard. In other words, no special provisions have been made to distinguish tiny experimental projects from massive dams. The agency is likely to streamline the process, however.

FERC is also trying to address concerns about "site banking" - shell companies hogging the best sites by attaining preliminary study permits, much as Internet squatters snag promising domain names. Attorneys for the city of San Francisco, in a filing this summer to FERC, went so far as to warn of "the risk of sparking a 'gold rush' by ill-prepared applicants with ill-conceived projects."

Developers must generally get a separate permit from the Army Corps of Engineers and also consult with the Coast Guard. Plenty of other federal agencies give input to FERC as well, including the National Ocean and Atmospheric Administration and the U.S. Fish and Wildlife Service, and each project will receive scrutiny at the state and local levels. There is also a lively debate about whether FERC or the Minerals Management Service should have jurisdiction for offshore projects in federal waters, which begin three miles offshore.

It took Verdant Power, operator of the tidal project in New York, almost four years to get its turbines operating, according to Trey Taylor of Verdant. He complains that regulators wanted the impossible: to understand the impact on fish even before Verdant started its experiment. "The regulatory processes need to be streamlined," he says.

But others fear that things are already proceeding too fast. "If the snowball starts to move, how do we stop it?" asks Muns. "We're not opposing this (but) we need to be sure that what we do is good."

The author is a freelance writer based in Seattle, Washington.