News and analysis about energy in California with an eye toward renewables.

Could California Run On Ocean Power?

California's ocean waves: a source of power? | Photo: Mike Baird/Flickr/Creative Commons License

In the last few weeks a European firm has tested its wave current turbines, a competitor in Texas announced it's working with a university to develop wave energy turbines, another ocean energy firm in New Jersey announced a similar R&D deal with a Japanese shipping company, and plans were announced to build a 50 megawatt wave energy power plant off the coast of Ecuador. The notion of generating power from the energy in the ocean is clearly picking up speed. But can it work in California?

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When you talk about turning ocean energy into electrical power, you're really talking about four related but distinct sources of energy. The most commonly proposed source of power is wave energy, the up-and-down movement of the surface of the water at frequencies of a few cycles per minute. Wave energy is essentially a secondary form of wind power, as waves are generated almost entirely by wind.

A wide range of mechanisms to turn that vertical motion into electrical power have been proposed, from stationary buoy-piston engines attached to seafloor-mounted pylons to Pelamis' truly weird "sea snake" wave energy converters, which generate power by the differential movement of jointed segments of large floating tubes, which forces hydraulic fluid through turbines. Pelamis' technology has actually generated commercial power, at the Aguçadoura Wave Farm off the coast of Portugal, seen in the embedded video:

The Aguçadoura installation went under, as it were, when the Portuguese firm Enersis that operated them had financial problems bestowed upon it by its owner, Australian firm Babcock and Brown, which went into receivership in 2009.

In addition to wave energy there's also tidal energy, the rise and fall of the sea driven by the gravitational interactions of the earth, moon, and sun, which cycles twice a day. There's energy from ocean currents, which generate their energy from a complex combination of solar energy, regional climate, and topography. And there's energy from temperature differential: water from the depths is colder than water closer to the surface, and that difference can theoretically be harnessed to run turbines. Sadly that difference isn't enough to make generating power at all economical, for the moment.

But wave, tidal and current energy offer promise. Estimates of the United States' theoretical capacity for generating electrical power from ocean waves at 2,610 Terawatt-hours per year, a bit more than 10% of our total energy consumption. Tidal energy could theoretically chip in another 440 terawatt-hours per year or so. A large percentage of both of those numbers could come from the coast of California. According to a report released this month by the consulting firm Global Data, it's theoretically feasible for California to meet 20% of its energy consumption needs from wave energy. Tidal power off the California coast offers as much as 1,787 terawatt-hours per year of power, about seven times what the state consumes. As the ocean's waves and tidesrise and fall pretty much 24/7 regardless of whether the wind is blowing in the immediate vicinity, that would be base-load power -- allowing us to replace coal- and gas-fired power with renewables without developing fancy storage technology.

There are two big problems. One: the technologies involved are largely unproven and implementing them would be expensive. Two: The ocean along the California shore is important habitat for many kinds of wildlife, and industrializing it will bear certain non-economic costs as well.

That second problem is likely to be the bigger one. Californians have fiercely defended their coast from oil exploration since the Santa Barbara oil spill of the late 1960s, and wave power proposals seem not to be any more popular than oil rigs. The firm Green Wave Energy Solutions lost a permitting battle in August over a years-long plan to install hundreds of wave energy generators in a 17-square-mile patch of ocean off Mendocino, and vociferous local opposition played a crucial role in the final spiking of permits for feasibility studies of the proposed 100 megawatt project by the Federal Energy Regulatory Commission (FERC). FERC rejected a similar proposal by Green Wave for studies preliminary to a 100-megawatt facility off Montana De Oro State Park in San Luis Obispo County in March.

Critics of GreenWave contended that the company didn't have the resources to carry out even the preliminary studies it was proposing, much less a full-scale wave energy construction project. GreenWave's Mendocino proposal rejected by FERC in August was nearly a carbon-copy of a 2007 proposal by the same company. FERC granted a preliminary permit for that earlier iteration of the Mendocino project, and was promptly sued in the U.S. Ninth Circuit by a group of environmental and fisherman's organizations and local cities. The case never made it to trial, as FERC cancelled the permit in 2011 after GreenWave missed too many reporting deadlines for the agency's liking.

GreenWave then refiled its application for the Mendocino proposal with FERC, and then -- according to FERC -- blew through another set of reporting deadlines.

The group Fishermen Interested in Safe Hydrokinetics, lead plaintiff in the Ninth Circuit case, suggested in a filing on the second proposal that GreenWave had objects other than renewable energy in mind in keeping the proposal alive:

According to the best information currently available, GreenWave has been used solely as a vehicle to further to the political ambitions of California State Senator Tony Strickland (R-Moorpark). ...

In 2008, Strickland ran for the California State Senate in the closest state senate race in California that year. As a private citizen, he was required to state his occupation for the public record. Based on his position with GreenWave, Strickland claimed that he was a "renewable energy businessman" throughout the election, and extensively publicized the GreenWave connection as a selling point in his campaign.

Now, predictably, the next election cycle has come around, and GreenWave is back in front of FERC again with a new application filed in September 2011. In January 2012, Strickland announced that he is running for the U.S. Congress in the newly reconfigured California Congressional District 26 in 2012. District 26 is a swing district that could help determine partisan control of the U.S. House of Representatives. His latest official disclosure form, which was filed on March 1, 2012, continues to list his business position as Vice President of GreenWave, and states that he has a stake in the company worth
somewhere between $10,001 and $100,000.

At least for now, political ambition or no, GreenWave's proposals ocean energy proposals are dead in the water.

Two other credible proposals for wave energy projects have been advanced in California, with backing by a company that definitely has the wherewithal to build large power plants -- Pacific Gas & Electric (PG&E.) Both have been withdrawn as well. The utility's "WaveConnect" project would have built two large testing sites, one off the Humboldt Coast and the other off Noyo Harbor at Fort Bragg, to test a number of different kinds of technology to convert wave energy to electrical power, including Pelamis' devices and piston buoys.

PG&E has since abandoned both projects, dropping the Mendocino WaveConnect portion in May 2009 due to engineering problems with Noyo Harbor, and then letting the Humboldt portion die a quiet death in 2010 despite that county's more salubrious setting. In a February 28, 2011 "progress report" to FERC on the project, PG&E spelled out the reasons for dropping the project altogether:

[N]umerous economic, regulatory, technical, siting, and environmental challenges slowed the Project's progress. Also, the current state of wave energy technology, the numerous financial hurdles and the evolving regulatory process made Project development excessively challenging.

What were those environmental challenges? The State Water Board's scoping comments on the Humboldt WaveConnect project pointed out that disturbance to the seafloor from installation of wave energy converters and laying of cable was of serious concern, as were leaks of hydraulic fluid or lubricating oils into the marine environment.

Comments filed in March 2012 on the GreenWave Mendocino project by Fishermen Interested in Safe Hydrokinetics spell out the habitat values potentially placed at risk by that project:

The project area contains numerous fisheries resources... including important marine fish species such as salmon and groundfish, shellfish such as crab, abalone, and sea urchins, and other plants and animals (including edible seaweeds) that inhabit the rocky intertidal zone. These fisheries resources will be affected by the proposed project. The gray whale migratory path between Alaska and Baja California is located within the project area. Both the whales themselves and the whale watching charter boats based in Noyo Harbor will be affected by the proposed project.

Species (and habitats) in the area listed under the federal Endangered Species Act (ESA) include eight species of salmon and steelhead, four species of sea turtles, black abalone, and green sturgeon. There are almost two dozen different marine mammal species that frequent the area to various degrees, about a third of which are ESA-listed. The project area also includes officially-designated essential habitat for a large variety of Pacific groundfish species, several coastal pelagic species, and chinook and coho salmon.
Effects of wave energy development within and near the project area that concern the FISH Committee include, but are not limited to: impacts on salmon and groundfish stocks, Dungeness crab, pink shrimp, sea urchins, eels, abalone, and edible seaweeds; physical exclusion from fishing grounds; effects on vessel transit in and around the project area; effects of construction, maintenance and operation of the project on the ecosystem and on the area's limited port facilities; alteration of currents and waves; alteration of substrates and sediment transport and deposition; alteration of habitats for benthic organisms; emission of electromagnetic fields; and interference with animal movements and migrations.

The biotic surroundings of the two PG&E WaveConnect proposals are substantially similar.

So four wave energy projects in California have foundered on the rocks, but there's another ocean energy project that's still afloat, and it's another PG&E venture. Rather than converting wave energy to power, this one looks at harnessing tidal currents in California's largest estuary: the San Francisco Bay.

A 2006 report by the Electric Power Research Institute said that San Francisco Bay's mouth -- also known as the Golden Gate -- is one of the best places on the West Coast for harnessing tidal power. Twice a day the full force of the Pacific Ocean surges in through the mile-wide strait between San Francisco and the Marin Headlands, and tidal power enthusiasts have long suggested that harnessing that flow might prove a profitable source of power. In 2006 PG&E agreed to work with Golden Gate Energy Comany, a subsidiary of the ocean power firm Oceana Energy, to assess the feasibility of harnessing flows through the San Francisco Bay for power. Testing in 2007 of flows between Alcatraz Island and the Tiburon Peninsula -- the deepest part of the Bay with the fastest tidal flows -- apparently proved encouraging, and Golden Gate applied to FERC for a permit to proceed with testing its submerged tide power conversion equipment.

Those tests haven't taken place yet. Soon after getting its permit in 2010, Golden Gate went through some staffing issues that caused it to miss FERC reporting deadlines. FERC warned Golden Gate Energy on September 1, 2010 that its permit would be canceled unless the company started meeting deadlines. Since then, the company has asked for several deadline extensions on its license application for the project as it reconfigures its scenario for testing its mockup turbine, which would be between 3 and 10 feet in diameter. The company has changed proposed testing locations at least once, and oscillated between planning to suspend its mockup from a stationary barge or placing it in a cage on the Bay floor.

While wave energy can be tapped using mechanical devices that might well pose little physical danger to wildlife, turning current flow to energy generally involves fan blades, which introduces some of the same threats to wildlife that conventional wind turbines pose. Siting a tide current power plant in a way that it will generate power as efficiently as possible without becoming a seafood Cuisinart will likely be very difficult in a place as crowded as the San Francisco Bay. Would-be tide harnessers must also avoid creating hazards to commercial navigation and to recreational Bay users. FERC's most recent deadline for Golden Gate's draft license application is December 1. If Golden Gate meets that deadline, the public will have 90 days to comment on it. San Francisco Bay has thousands of passionate advocates, and the comment period will likely be contentious. And it doesn't help that other agencies have reported San Francisco Bay tidal power would cost millions of dollars to build, $750,000 a year to maintain, and provide one or two megawatts' worth of power at best.

Aside from a short-lived proposal to power the city of Avalon on Catalina Island by wave-power converting buoys, which lasted about 18 months before FERC pulled the permits, that's it for ocean power in California: one struggling project that many critics have already blasted as far too expensive. It may well be possible that Californians 100 years hence will derive much of their power from the Pacific Ocean. But unless some of this month's initiatives elsewhere in the world do a lot better than previous Californian attempts, don't hold your breath.

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About the Author

Chris Clarke is a natural history writer and environmental journalist currently at work on a book about the Joshua tree. He lives in Joshua Tree.
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