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Off-shore wave energy system to be constructed

By Bill Jaynes

POHNPEI, Federated States of Micronesia (Kaselehlie Press, Dec. 2, 2011) - In Kosrae, the FSM’s easternmost State, fossil fuel powered electrical generation is doomed; headed for extinction; gone the way of the dinosaurs. Kosrae will likely be the first island State in the world to be entirely powered by renewable energy.

A joint venture between Kosrae Utility Authority (KUA) and Ocean Energy Industries, Inc., U.S. under the corporate name of Ocean Energy Kosrae (OEK) will harness ocean wave power capable of delivering all of Kosrae’s current electrical needs and then some.

"KUA and Kosrae are very optimistic and looking forward to being entirely powered by renewable energies in the next two years," wrote KUA representative, Fred Skilling in an email.

"The new corporation (OEK) already secured the Foreign Investment Permit and had registered and chartered under the State of Kosrae," Skilling wrote. "The site selection and data collection with the plant design and layout are currently underway. Construction and installation of the system is expected to commence within the next seven to nine months," he wrote.

The planned wave powered system will generate 1.5 megawatts of power 400 kilowatts more than Kosrae’s current peak demand which Skilling said currently is at 1.1 megawatts.

Kosrae already has a renewable energy system connected to its power grid. An EU funded solar photovoltaic (solar PV) system is already providing 47 kilowatts of power capacity to help KUA reduce its dependency on fossil fuels. The EU is working with KUA to increase the solar PV system capacity to 300 kw which would be able to provide more than 27% of Kosrae’s current peak electrical power demand further reducing KUA’s reliance on fossil fuels for electrical generation.

Not only will the planned energy method be clean but KUA’s customers can anticipate a significant price break as well. Skilling said that KUA customers currently pay an average of 45 cents per kilowatt hour for electricity that is being generated by the diesel powered plant.

"The Power Purchase Agreement between OEK and KUA has already agreed on a starting rate that will slash more than half of the current rate," Skilling wrote. The rate will be subject to review every five years.

According to a republished article written by Toby Price, the agreement between Ocean Energies Kosrae and the Kosrae Utilities Authority is for a term of 25 years, "guaranteeing a customer for the output produced by the innovative wave convertor."

The wave convertor technology is proprietary to Ocean Energy Industries. The company has developed wave convertor systems that range in output from 1 kilowatt to 10 megawatts of clean electrical energy.

"The WaveSurfer offshore system is described by its developers as a ‘point absorber’, installed at a variety of depths using moorings. WaveSurfer's main power conversion and generation components are completely submerged at a depth of between 8 and 25 metres. Ocean Energy Industries says that this system ‘results in amazing survivability of each unit capable of withstanding extreme storms without any damage that would affect the unit's performance,’" the press release said.

Not only will the wave convertors mean a lower power bill for KUA utilities once it is in operation, the elimination of diesel powered generators will further reduce Kosrae’s already small contribution to worldwide carbon emissions. The manufacturer of the wave generator system says that it is estimated that every kilowatt hour of energy produced by fossil fuels produces 0.43 kilograms of carbon. Ocean Energy Industries calculates that each 20 kilowatt converter will save over 40 tons of carbon dioxide that would otherwise be released by diesel generators into the atmosphere each year. At Kosrae’s peak demand of 1.1 megawatts, the system would reduce carbon emissions by nearly 2000 tons per year.

The WaveSurfer is designed to operate in harmony with the waves rather than attempting to resist them. Because of this fact massive steel and concrete structures are not needed. Each WaveSurfer would be installed in water deeper than 15 meters (nearly 50 feet) in areas where there are no breaking waves. The units would have no impact on popular surfing sites because breaking waves actually equate to lost energy.

"The device also offers a high and fast return on investment, since it has the ‘lowest construction cost per kilowatt capacity and lowest energy production cost per kilowatt hour in the industry," the news article says.

The environmental impact of collecting wave energy is not completely understood. Currently there is a major acoustic measurement study of the technology that is taking place in two locations off the coast of Ireland. IBM and The Sustainable Energy Authority Ireland are working on the project in order to understand and to minimize the environmental impact of converting wave energy into electricity. It is the first project to utilize real-time streaming analytics for monitoring underwater noise generated by wave energy conversion devices.

The WaveSurfer team worked for over nine years to identify the wave energy environmental issues, their possible impacts and mitigation strategies. All of the WaveSurfer projects underwent extensive environmental assessments with assistance from The Marine Hydophysical Institute of the Academy of Sciences of the Ukraine.

"The project study resulted in a finding of no significant impact (FONSI), which is the highest such environmental rating," the WaveSurfer Environmental Impact Assessment says.

"All energy producing technologies, and for that matter, all human endeavors in general, and ocean energy conversion in specific, have the potential to produce environmental impact," the assessment says. "Given proper care in siting, installation, operation and decommissioning, ocean energy technology is one of the more environmentally benign electricity generations technologies. Most known negative environmental effects can be minimized and in some cases eliminated by diligent attention to the environmental effects."

"WaveSurfer technology has insignificant environmental impact, the environmental assessment concluded.

According to the assessment the system may actually provide multiple environmental benefits as nine years of experience has shown. The portion of the system that will be on a platform at the surface of the water will likely also function as a fish aggregating device (a FAD) and the cables that will hold the systems in place will likely become artificial reefs. The unit’s floating device may be colonized by seabirds.

In other places the floating platforms have been used by pinnipeds (seals, sea lions, and walruses) as "hauling out" space.

The system is not an impervious barrier to waves traveling shoreward. "Gaps between the units and less than 100 percent absorption efficiency allow considerable wave energy to pass through the plant," the assessment says. Still, there could be some lowering of wave energy levels reaching the coast that could reduce erosion in the site’s wave shadow.

The floating WaveSurfer devices will need to be marked appropriately as navigation hazards but the markers are expected to have "negligible visual impact when viewed from shore." Because of their "low-freeboard" design the floating platform that is part of the generation system "are visually intrusive on the seascape as viewed from the shore, even from elevated shoreline positions."

The system does not use oil, lubricants or any other potentially harmful chemicals.

The Environmental Impact Assessment says that there may be "minor and temporary impact from electromagnetic emission on marine organisms in the vicinity of the submarine hub, transformer and cables.

In the unlikely event of submarine cable damage "mild and temporary discomfort for marine organisms and divers could occur."

Construction and installation of the technology is expected to begin in six to nine months.

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