Marine Hydrokinetics Technology: Market Acceleration

Sandia National Laboratories is leading research to describe and quantify environmental impacts caused by new and existing marine and hydrokinetic (MHK) technologies. The team will evaluate environmental factors including rates of sediment transport, water flow, water quality, and acoustic changes. The results will help quantify the types and magnitude of environmental impacts for various new and existing technologies. Researchers will collaborate with industry to develop criteria for selecting locations for projects and select technology to monitor and mitigate such impacts. Sandia is partnering with Oak Ridge National Laboratory (ORNL), Pacific Northwest National Laboratory (PNNL), and Argonne National Laboratory (ANL) in this work.

Categorizing and Evaluating Effects of Stressors

This task will focus on data organization and impact evaluation. PNNL and ANL will lead and cooperate on organizing and analyzing existing information on environmental effects of MHK devices and systems, as well as provide for the addition and expansion of new information. A knowledge management framework named Tethys will be developed that brings together existing information on environmental effects of MHK technologies and commercial development. This Tethys will allow for the incorporation of new information as it becomes available, assess the level of certainty with which we can assess impacts, and provide output for multiple investigations of MHK effects.

PNNL will also lead the development of an international impacts database as part of IEA Annex IV to support assessments of MHK stressors from case studies from Annex member nations. The international database will be housed and support by the Tethys. Individual and multiple stressors of MHK devices will be addressed by PNNL through the development of an environmental risk evaluation system (ERES) that will use risk assessment techniques to determine priority stressors on aquatic animals and environments from specific MHK technologies. The ERES will also identify important data gaps where future research may be needed. ANL will also address the impacts of stressors by characterizing how MHK operations (at both the individual unit and commercial development scales) may impact biological resources in marine and freshwater systems. This task will develop approaches for evaluating the potential individual and cumulative impacts of MHK operations on ecological resources (e.g., sea turtles, marine mammals, benthic organisms) and ecological attributes (e.g., nesting beaches for sea turtles) in marine and freshwater systems, and develop potential mitigation measures for specific aspects of MHK project development.

Other tasks within the project will produce new information that will be added to the knowledge management system to enable improved future analyses. Permitting and planning will provide access to information and stakeholder needs that will help to drive the ERES and improve the knowledge system.

In summary this task has the following objectives:

• Bring together information about the environmental effects and use conflicts caused by MHK devices to determine the impacts of individual and multiple stressors, and to evaluate the certainty of the information.
• Develop an international impacts database and make output of the database accessible for investigations for IEA Annex IV member nations.
• Develop resource-specific conceptual site models that link specific ecological resources and attributes with specific MHK stressors.
• Perform analyses to characterize how the operation of individual and arrayed MHK devices might impact ecological resources and attributes.
• Develop an approach for performing cumulative impacts analysis of MHK effects in the context of other anthropogenic stressors.
• Develop potential mitigation measures for specific aspects of MHK project development.

Effects on Physical Environment

This task will assess changes to the physical environment (i.e., currents, waves, sediments, water quality, and food web) potentially imposed by the operation of various types of MHK devices and arrays in marine and riverine environments. Sandia and PNNL will employ measurement tools and computational models to simulate the marine and riverine environments before and after device installation. By using models to simulate processes such as water circulation and sediment transport, the consequent changes in water quality, benthic habitat quality, and aquatic food webs may be predicted. Scenarios can be developed that examine the limits of environmental changes that may occur in specific aquatic areas before unacceptable environmental degradation occurs. In the second and third years of the project, simulated single MHK devices will be added to the models, followed by simulated arrays of devices. We will simulate scenarios of impact, as well as alternative geometries of arrays and devices. These simulations and scenario analyses can provide cost-effective planning tools for use before proceeding to detailed siting, engineering designs, and deployment of devices.

We will use the following objectives to systematically assess the potential physical and chemical impacts caused by MHK-driven energy extraction from marine and freshwater systems:

• Develop and apply hydrodynamic, sediment dynamic, and water quality models that simulate the effects of MHK devices and arrays on marine and riverine systems.
• Examine the effects of MHK device operations on currents, waves, water quality, sediment dynamics, benthic habitats, and aquatic food webs.
• Create scenarios that simulate the effects of single MHK devices and arrays in specific aquatic environments.

We will disseminate the results of this work to industry, regulators, and stakeholders via conferences, meetings, reports, publications, and specific activities. This work will also be provided to the conceptual models, risk-informed framework, and the knowledge-management system.

Effects on Aquatic Organisms

Here, we will examine direct effects of MHK devices on aquatic organisms, with early emphasis on the effects of electromagnetic fields (EMF), acoustic noise from current/tidal, wave and riverine hydrokinetic generators, toxicity from coatings and lubricants, biological response to alteration of benthic habitat, and physical interaction of organisms with fixed and moving MHK structural components. We will publish and distribute study results for use by industry. As appropriate, information gained under this task will be added to the knowledge-management system, used to refine the risk-informed process, and used to evaluate the cumulative effects of multiple stressors.

Studies under this task will address the following objectives:

• Determine realistic levels of EMF exposure from MHK devices in marine and freshwater systems and the effects EMF has on aquatic organisms.
• Determine realistic levels of acoustic output from MHK devices and the effects that the noise levels may have on marine and freshwater organisms.
• Evaluate the potential toxic effects of antifouling coatings and other chemical contaminants on aquatic organisms.
• Evaluate the response of aquatic organisms to physical changes in bottom habitats caused by installation and operation of MHK devices.
• Develop a preliminary assessment of the potential physical interactions (particularly strike) of marine and freshwater organisms with MHK devices, leading to laboratory- and field-based strike studies.