MHK Research Tools for Water Power Industry

1. Water Power Peer Review Richard Jepsen Sandia National Labs rajepse@sandia.gov; 505-284-2767 November 2, 2011 MHK Research, Tools, and Methods

2. Purpose, Objectives, & Integration The MHK industry is at a nascent stage of development and a recent surge of interest has produced over 100 new device concepts and designs for extracting energy from waves, tides, ocean and river currents. Improved testing, analysis, and design tools are needed to more accurately model operational conditions, to optimize design parameters, and predict technology viability. This will allow for existing analysis tools and methods to be evaluated and validated. In addition, new codes and materials will be developed and validated. Most importantly all these tools, formulations and test data will be accessible to industry. This project has direct applications to other projects in Reference Model Development and Market Acceleration as the tools developed here can be utilized to predict and guide performance metrics.

3. Water Power Program Chart Developed with NREL Collaboration with NREL & ORNL Collaboration with NREL & PNNL

4. Technical Approach Each analysis tool is being developed and/or validated against previously reported test results or new tests conducted with project funding specifically for this purpose. There are at least three unique tools being developed by Sandia that are not commercially available that aid in design and performance evaluation of MHK devices or arrays. In addition, there is a strong link to the Reference Model project in which each reference model serves as a benchmark case to apply and evaluate analysis tools. Finally, collaboration with NREL on high fidelity modeling and testing activities allows further validation for analysis tool performance metrics. For the Materials and Coatings testing, Sandia is collaborating with industry partners from coatings manufacturers to MHK developers to evaluate existing samples under various marine conditions. In addition, Sandia is developing unique anti-fouling coatings for MHK applications. In all cases, Sandia is working with ORNL to test adverse toxicity issues with each coating and material investigated.

5. Plan, Schedule, & Budget Schedule: The following are significant milestones or deliverables for the project: • Release and offering of training classes for SNL-EFDC Current and Tidal Array performance analysis. August, 2011 • Release and offering of training classes for SNL-EFDC WEC performance analysis. August, 2012 • Release of CACTUS (Code for Axial and Cross-flow Turbine Simulation) code for Marine Turbine performance analysis. September, 2012 • Design, analysis and validation testing of high performance turbine. September, 2012 • Report on evaluation of existing marine coatings. September, 2012 • Report on evaluation of newly developed marine anti-fouling coatings. September, 2012 • There are currently no foreseeable Go/no-go decision points for FY12 and FY13 Budget: • The only variances from the planned budget are reductions for FY12 based on Program constraints. This has resulted in some incremental reduction across all activities and the removal of reliability efforts from FY12 plans. Other than reliability milestones, no other milestones or deliverables are affected for FY12. • 73% of the budget has been invoiced *SNL budget only for direct costs and contracts to university partners. Does not include funding (~$650k) to other National Labs

6. Accomplishments and Results The following highlights the most important technical accomplishments achieved during this reporting period: • Preliminary implementation of WEC arrays in SWAN/SNL-EFDC model with validation testing for WEC array at OSU (with CPT) • Application of AQWA/Simulink model for WEC on Reference Model (with OSU) • Development, validation and release of SNL-EFDC for current and tidal turbine arrays. • Development and validation of CACTUS with wind data set from vertical axis testing. • Development and patent application for promising new coating technology. • Successful testing and demonstration of high resolution shear stress measurement in Sandia SEAWOLF flume for wave sediment interactions. • The project has been on schedule and on budget thus far and the progress suggests continued success in this regard. All of the above accomplishments have corresponding milestones that were completed on schedule and on budget

7. Wave Device Modeling • Single Device • Integrate Fluid-Structure interactions with performance modeling including PTO • Device Arrays • Represent devices as reflection and/or transmission sink • Integrated into SWAN/SNL-EFDC No WEC Array 17 WEC Array

8. WEC Array Testing for Model Development and Validation • Goal: In collaboration with OSU and Columbia Power, generate test data for WEC arrays to support code development and validation. • Motivation: Once completed, this experimental test matrix will provide a basis for model validation and allow for a performance modeling tools for optimization WEC arrays

9. SNL-EFDC for Current and Tidal Array Performance • SNL-EFDC has been developed to include MHK devices as momentum/energy sinks • The model is partially validated with more tests planned in the laboratory and field (ORNL, UW, UM/SAFL) Flow Direction • 0 Platform Spanwise Spacing = 12 Platforms per array row • 27% more power per row than 1PH (for 100% more turbines) • 44% more power per row than 2PH (for 200% more turbines) • 1 Platform Spanwise Spacing = 6 Platforms per array row • 23% more power per row than 2PH (for 50% more turbines) • 31% more ‘platform average power’ per row than 0PH • 2 Platform Spanwise Spacing = 4 Platforms per array row • 40% more ‘platform average power’ per row than 0PH • 13% more ‘platform average power’ per row than 1PH

10. Single Turbine Modeling • Single Device • Development of CACTUS Code for both cross flow and axial flow turbine analysis • Design and test of high performance turbine blade (with Penn State ARL and UC Davis)

11. Turbine Testing Penn State ARL: Model testing for blade and turbine performance Bucknell University: Model testing for foundation performance and scour

12. Materials and Coatings • Montana State University • Moisture Absorption • Mechanical Testing on salt water immersed composites • Fabrication

13. Materials and Coatings • Evaluated the first set of antimicrobial treated materials from Owens-Corning for their ability to mitigate biofilm growth and adhesion towards the marine bacteria, Cellulophaga lytica and Halomonas pacifica, and the microalgae diatom, Navicula incerta. • No substantial reduction in bacterial or microalgae biofilm growth was observed for the experimental • coatings. • NDSU • Biofilm Characterization of Owens-Corning • Also characterized all of SNL materials N. incerta C. lytica H. pacifica

14. Materials and Coatings • SNL • Biofilm baseline measurements on commercial materials & coatings

15. Challenges to Date The primary challenges for the project have been related to funding reductions and uncertainties. The project subtasks were prioritized such that the most mature and promising developments were maintained while subtasks such as reliability which will be more important in future years as deployments increase were removed.

16. Next Steps Wave Analysis: • Wave design tools development roadmap • Further model development and validation for WEC arrays. Release 1st version of SNL-EFDC model for WEC arrays end of FY12. Current and Tidal Turbine Analysis • Additional training planned for developers on a first come first serve basis • Validation testing in the field (with developer support) and lab for SNL-EFDC model • Water tunnel testing for blade and turbine performance validation (blade design and CACTUS performance) Materials and Coatings • Continued work on Owens-Corning, Verdant, Free Flow Power Biofilm Characterization • Sending samples to ORNL for Toxicity, ARL for cavitation • Continue to optimize synthesis of new anticorrosion/biofouling coatings