Water Power Peer Review

1. Water Power Peer Review PB150 (Scotland) Dr. Philip R. Hart Ocean Power Technologies 1590 Reed Road, Pennington, NJ 08534 609-730-0400 x263 prh@oceanpowertech.com Sept 27, 2011 PB500, 500kW Utility-Scale PowerBuoy Project

2. Purpose, Objectives, & Integration This project focuses on the advancement of the OPT PB500 (500kW) PowerBuoy design, from TRL 4 to TRL 5/6. • Design refinement requires extensive engineering and cost analysis, in a relatively short period of time. • Hitting operational characteristics targets are challenging and requires careful analysis of all factors involved in producing, deploying, and maintaining a PowerBuoy of this scale. • Power-Take-Off (PTO) Mechanism subassemblies require risk mitigation testing to ensure that the performance and reliability is as specified. • PTO Mechanism assemblies require risk mitigation testing to ensure that the effect of combining technologies and subassemblies are carefully examined. • Integration of PTO assemblies into the PTO system require risk mitigation to verify operational characteristic and ensure there are no interferences. Solving the problems above allows for the realization of competitive energy pricing in the global marketplace. The results of this project under DOE grant DE-EE0003645 will be used to conduct detailed design, fabrication, and assembly of PB500 PowerBuoy.

3. Technical Approach The technical approach: • Stage-gated development program with clearly defined stage reviews. • Clearly defined stage deliverables. • Overseen by interdepartmental management and peers prior to proceeding to the next stage (go/no-go decision). Key issues: • New technology adoption at the subassembly and assembly levels may introduce new technical risks • New Modular PTO approach could introduce packaging and arrangement issues • Scale-up increases structure loading. • Scale-up additionally places more emphasis on installation costs and maintenance considerations. Unique approach: • Rigorous subassembly and assembly testing to mitigate subsystem and system technical risks. • Final PTO integration testing to ensure the implementation of new technology and arrangement does not introduce interference and alter PTO operational characteristics. • Highly developed simulations/modeling validated by test. • Extensive wave tank and ocean testing experience.

4. Plan, Schedule, & Budget Schedule • Grant Initiation date: 9/1/2010 • Planned completion date: 9/30/2012 FY 2011 • Stage Gate 4 (Survival Condition Wave Tank Testing). 8/12/2011. (Complete) • Stage Gate 4 (Survival Condition Wave Tank Testing Data Analysis). 9/30/2011. FY 2012 • Operational Condition Wave Tank Testing. 12/19/2011. • PTO Preliminary Design (OPT SG5) Completion. 2/18/2012 • PTO Detailed Design (OPT SG6) Completion. 4/27/2012 • Structural and Mooring Concept Design (OPT SG4) Completion. 4/27/2012. • PTO Prototype Fabrication, Assembly, and Testing (OPT SG5) Completion. 7/31/2012 • Structural and Mooring Preliminary Design (OPT SG5) Completion. 9/30/2012. • Go/no-go decision points will be made at the completion of each stage gate identified above.

5. Plan, Schedule, & Budget Budget: • There were no significant budget variances. • 6% or $145,593 out of the total grant amount of $2,400,000 has been expended to date (August 31,2011)

6. Accomplishments and Results Technical Accomplishments: • Completion of survival condition wave tank testing, setting the baseline design criteria that must be met (project milestone). • Float geometries set for acceptable modular PTO interface, bounding the float design to allow the use of the MPTO. Benchmark against technical targets: • Above accomplishments do not relate directly to technical targets, however initial cost estimates on current rough design are approaching the specific lifecycle cost targets as defined in the project objectives.

7. Challenges to Date Most important challenges: • Selection of optimal float geometry • Selection of optimal “mooring” method • Integration of subsystems and systems in PTO Approach to issues or challenges faced: • Largest issue or challenge faced to date is driving the lifecycle cost down while designing a robust, safe, and efficient PowerBuoy. Costs have been driven down through a careful design concept selection process, overseen by cross-departmental team members.

8. Next Steps Project plans (PB500 Structural and Mooring Design (OPT SG4) under DOE grant DE-EE0003645): Task Name % complete Start Finish Wave Tank Testing – Survival Cond. 100 07/11/11 09/30/11 Wave Tank Testing – Operational Cond. 20 08/22/11 01/13/11 Tidal Compensation Concept Design 20 08/22/11 10/14/11 Latching and Locking Concept Design 0 10/17/11 11/11/11 Input Rod & Linear Seal Concept Design 0 10/24/11 11/18/11 Central Cooling System Concept Design 0 11/07/11 12/09/11 PTO Assembly Concept Design 0 11/07/11 12/09/11 Structure and Mooring Concept Design 0 11/17/11 02/17/12 Float Concept Design & Arrangement 0 02/20/12 03/16/12 Ballasting System Concept Design 0 03/27/12 03/23/12 PowerBuoy Deployment Concept Design 0 03/26/12 04/20/12 Conduct Stage Gate 4 Review 0 04/23/12 04/27/12

9. Next Steps Project plans (PB500 Power-Take-Off Preliminary and Detailed Design- OPT SG 5/6 under DOE grant DE-EE0003645): Task Name % complete Start Finish Assembly of PTO subsystems 0 10/03/11 10/21/11 Risk Mitigation testing of subsystems 0 10/24/11 11/18/11 Assembly of PTO systems 0 11/21/11 12/23/11 Risk Mitigation testing of PTO systems 0 01/02/11 01/27/12 Conduct PTO Stage Gate 5 Review 0 01/30/12 01/31/12 Assembly of PTO Mechanism 0 02/01/12 03/30/12 Functional Testing of PTO Mechanism 0 04/02/12 05/11/12 Cycle Testing of PTO Mechanism 0 05/14/12 07/13/12 Generate PTO Test Report 0 07/16/12 07/27/12 Conduct PTO Stage Gate 6 Review 0 07/30/12 07/31/12 • End of project for DOE grant DE-EE0003645 is scheduled for 8/31/2012.

10. Next Steps Next steps: • Plans for expansion and continuation of all work produced in this project would provide scope for a follow on DOE (or commercial) project. • Construction of full-up PTO systems for PB500. • Integration and assembly of PTO systems into PB500 unit. • Construction of a full scale PB500 structure and mooring. • Deployment/installation of the first PB500. • Operation, Monitoring and Maintenance of first PB500.