Feature Articles—September 2009 Issue
Challenges in Regulating The Open-Ocean Energy IndustryAssessing Engineering and Regulatory Gaps for Wave and Current Energy Installations
on the Outer Continental Shelf
By Robert Cinq-Mars
President Free Flow Energy Inc.
Lee, New Hampshire
In late 2008 and early 2009, Free Flow Energy (FFE) conducted a study on the standards for wave and current energy-generating devices on the Outer Continental Shelf (OCS).
Under contract with the U.S. Minerals Management Service (MMS), FFE reviewed wave and current energy-conversion technologies, related engineering standards, and existing inspection and monitoring approaches to identify safety and regulatory concerns. FFE then performed a gap analysis to identify elements missing from design and inspection criteria and standards.
This article reviews selected safety and regulatory gaps that the MMS and other regulatory bodies confront as they work to facilitate the safe and productive development of offshore renewable energy development while protecting natural resources and without compromising national security.
Nascent Industry, Limited Testing
Offshore wave and current energy conversion is an early-stage industry with many unknowns. A wide range of technologies—some rooted in patents decades old—are being developed to harness this renewable resource for the generation of electricity. At this point, no definitive leading designs have emerged for wave or current energy conversion, although a vast array of electromechanical devices are in the development and test stages.
Wave and current energy-conversion devices exhibit varying dynamical behavior and thus have varying structural requirements. Ensuring compliance with installation, operation, maintenance and decommissioning specifications requires regulators to address multiple engineering principles. Also, effective offshore alternative energy conversion involves a system, not just a device. In addition to components that convert wave and current energy to electrical power, regulators also must consider supporting structures, control and monitoring systems, anchors and moorings, transmission components (e.g., a cabling and grid-interconnection apparatus), and shore-based support facilities.
Standards for Offshore Energy
Organizations are currently developing engineering standards for marine energy conversion, yet only a few have been written specifically for wave and current facilities, equipment and operations. Although overlap exists between offshore renewable energy conversion and existing offshore oil and gas industries, exploiting that overlap too heavily can render standards too general—and thus less effective. Also, whereas oil and gas platforms are designed to minimize the loading impact of waves, wave and current-driven devices are designed to absorb and capture this energy source.
A number of factors affect the identification of standards relevant to wave and current energy-conversion systems.
Offshore energy-conversion equipment is in the early stages of development; thus, designs vary dramatically and lack consistency. Energy-conversion equipment might be installed on the ocean surface, at various locations within the water column or on the seafloor. Some systems include energy storage or accumulation devices.
Organizations addressing engineering standards for wave and current energy-conversion systems include the International Electrotechnical Commission (IEC); the International Organization for Standardization; the European Marine Energy Centre (EMEC); the Ocean Energy Systems Implementing Agreement of the International Energy Agency; Oslo, Norway-based Det Norske Veritas (DNV); and insurance underwriters.
Other organizations involved in engineering standards development that could impact wave and current energy-conversion devices include the American Concrete Institute, American Institute of Steel Construction, American Petroleum Institute, American Society of Mechanical Engineers and the American Welding Society. The United States has representation on the IEC Technical Committee 114 (TC 114), which is specifically responsible for the development of standards pertinent to wave, tidal and current energy conversion.
Importantly, insurance underwriters will be instrumental in the implementation of offshore wave and current energy. In addition to developing guidelines for wave and current energy-conversion devices, insurance underwriters are promoting certification programs for marine energy, looking closely at the strength, reliability, safety and value of proposed installations.
FFE evaluated safety and regulatory gaps in five areas: wave and current energy-conversion devices, electrical transmission and interface, structural design, anchoring and mooring, and operations management. These areas extend across a number of disciplines, underscoring the complexity of energy-conversion systems configured for the OCS. Of course, all five areas are impacted by the harsh, corrosive and unpredictable ocean environment.
Energy-Conversion Devices
FFE identified several gaps related to wave and current energy-conversion devices, including the absence of specific design and construction standards, the inaccessibility of existing standards, the lack of formal plan-approval processes, the need for safety-sensitive engineering specific to wave and current energy conversion, and the need for equipment, manufacturer and parts certification.
No final, comprehensive standards exclusive to the hydrokinetic industry exist at present. The DNV published Guidelines on the Design and Operation of Wave Energy Converters in 2005, and the EMEC and TC 114 are developing standards, but these efforts have yet to produce formalized, widespread standards.
Gaps also exist in the engineering process because of the absence of specific design and construction standards. An inadequate engineering and plan-approval process can result in premature failure and even safety issues. Site developers will need to work closely with technology companies and regulatory agencies to circumvent these lapses.
The DNV guidelines mentioned above advocate a number of safety-related subsystems and considerations, including proper engineering documentation, safety system battery backup, safety and control system fault/alarm indication, alarm system self-monitoring, safety-critical system automatic restart and critical condition slowdown/shutdown. Although pertinent, these safety considerations do not consider some of the features inherent to wave and current devices. This is due to the fact that classification societies are confronted with a broad range of technologies and designs at varying stages of development, all with unknown likelihoods of implementation.
Finally, for proper design and installation approval, component suppliers should have the material or components that they are supplying certified. Many components specific to wave and current devices have not been specified yet, further confounding the certification process.
Security and Other Grid Issues
Power transmission and grid tie-in (i.e., subsea cable) and communications infrastructures pose homeland security risks. The more the United States becomes dependent on marine energy, the more vulnerable offshore wave and current energy installations will become. Accordingly, FFE recommends that conversion system operators submit a security plan in their development proposals.
In addition, the inadequacy of the grid infrastructure for renewable energy in the United States has been well documented. Grid shortcomings are particularly significant for ocean energy, both technologically and in terms of cost. In fact, the distance from an installation to the shore-based infrastructure and the adequacy of that infrastructure could determine the success or failure of some ocean energy projects.
Subsea power transmission and grid connection is not a new undertaking. Nevertheless, large-scale interconnection of offshore energy-conversion devices, the required power conditioning control systems and underwater, high-power-rated connectors will be technical and fiscal challenges.
Structural Safety
Significant information about sea-based structures is available from the offshore oil and gas industry. Nonetheless, FFE noted gaps related to applications of advanced composite materials in the marine environment for the construction of wave and current energy-conversion equipment and associated structures.
In particular, reliable prediction models for failures in composite material currently do not exist. Prediction modeling for composites employed in the marine environment is exacerbated for many reasons, including the delamination of epoxy coatings in saltwater, the dramatic change in flexibility properties as temperature changes, the anisotropic properties of plastics and the rapid disintegration of polysulfide sealants in some conditions.
Anchoring and Mooring Safety
FFE identified the interface between offshore electrical transmission components and the mooring systems required for wave and current energy-conversion devices as a notable technological challenge.
Although compliant cables for connecting surface or subsurface generators to equipment on the seafloor are under development, equipment is not yet available for the structures required for high-power, commercially viable wave and current power-generating devices.
Operations Safety
FFE found a large number of operations management safety and regulatory gaps, from risk assessment and emergency planning to navigational safety, training standards, diving operations, crane and lifting operations, and operating performance.
Because of the lack of operational experience in wave and current energy conversion, diligent and comprehensive planning and risk analysis will be paramount before any facility begins operations.
FFE recognized in its analysis the need for added steps in planning to include such activities as simulation modeling and in-situ testing of scaled equipment.
Inexperience creates similar challenges in emergency response planning, necessitating added levels of safety precautions and an emphasis on search-and-rescue operations.
All offshore marine renewable energy facilities will impact, to some degree, safe navigation.
Some wave and current energy-conversion devices could be particularly problematic because, unlike offshore wind facilities, they could be entirely submerged. Presently, the U.S. Coast Guard lacks sufficient experience with these devices to create an appropriate policy; some European organizations, however, have published guidance documents to address navigational issues.
As an emerging market, the offshore wave and current energy-conversion industry lacks minimum training standards. Industry players and regulatory agencies will need to address training standards and competency levels aggressively as the market develops.
FFE noted that commercial diving operations in support of wave and current energy-conversion operations face some unique risks. In addition to the risks inherent to diving, offshore wave and current systems add hazards and complexity because of the ambient energy levels of the environment and the exposure to subsea rotating and reciprocating equipment. Existing commercial diving procedures and regulations will require careful review and revision to ensure a safe and effective work environment.
With regard to operating performance, FFE recommends the development of a methodology for gauging a facility operator’s performance that is equivalent to the requirements set forth in the Code of Federal Regulations for conventional operations on the OCS. In addition, FFE recommends the implementation of a self-reporting system for determining operating performance that permits the operator to reduce the chances of punitive action and that encourages full disclosure of activities. FFE feels that to benefit the industry in general and to help it mature, operating performance information should be shared.
Conclusions
Wave and current energy conversion is a global undertaking, with research and development, testing and implementation occurring from Scotland to New Zealand. Many European companies, for example, hold leadership roles in marine energy conversion. Although the OCS is regulated by the MMS, FFE expects that many potential stakeholders involved in wave and current energy conversion on the OCS will be international organizations, and FFE advocates that the MMS and other U.S. regulators maintain an international perspective as regulations are promulgated.
Also, because a credible marine engineering industry exists worldwide, FFE encourages the regulators of and participants in offshore renewable energy conversion to take advantage of the existing technological expertise, knowledge and infrastructure.
FFE’s experience with hydrokinetic energy development suggests that wave and current energy conversion on the OCS will develop quite slowly. The environment is hostile and untested for energy conversion, and, understandably, offshore sites are not now preferred by developers. In addition, data on viable offshore ocean energy resources suitable for wave and current energy conversion need to be refined.
Adequate wave force or current flow velocity are not the only attributes of desirable offshore sites for energy conversion. The most attractive sites also will offer a deregulated power market, high electrical kilowatt-hour rates, limited electrical power availability from traditional means, strong renewable energy incentives and/or an existing electrical infrastructure.
Finally, regulations based on familiarity with emerging hydrokinetic energy technologies and the offshore environment can guide and facilitate the design, construction, operation, monitoring, inspection, safety and, ultimately, decommissioning of wave and current energy-conversion equipment, systems and facilities. This will, in turn, advance the development of this important industry.
As a former commercial fisherman and certified diver, Robert Cinq-Mars has spent years working on and in the oceans, and he possesses decades of engineering and renewable energy expertise. Cinq-Mars has actively contributed to and participated in the formation of the new and evolving Federal Energy Regulatory Commission and Minerals Management Service regulatory processes for new technology hydrokinetics. He earned a B.S. in electrical engineering at the University of Rhode Island.
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