1. 1 | Program Name or Ancillary Texteere.energy.gov Water Power Peer Review A First Assessment of U.S. In-Stream Hydrokinetic Energy Resources Since the NYU Study Paul T. Jacobson Electric Power Research Institute (410) 489-3675 pjacobson@epri.com November 3, 2011

2. 2 | Wind and Water Power Programeere.energy.gov Purpose, Objectives, & Integration This project will dramatically improve the state of knowledge of the theoretical hydrokinetic resource and the technically extractable electrical energy from U.S. rivers and man-made channels. By characterizing the magnitude and geographic distribution of the in-stream hydrokinetic resource, this project helps to define the potential role of hydrokinetic generation in meeting state and federal renewable energy goals and mandates. Such information can be used to inform Department of Energy decisions regarding allocation of R&D funding.

3. 3 | Wind and Water Power Programeere.energy.gov Technical Approach Both the theoretical and the technical In-Stream hydrokinetic resource is being estimated in the project. The theoretical resource in river sections throughout the US is being estimated according to γQ∆H, where γ is the specific weight of water, Q is the flow rate, and ∆H is the hydraulic head drop over the section. The resource is being estimated based on the annual average flow rate (available from the NHDPlus GIS system) as well as from the 5, 10, 15, etc. percentile flows (estimated based on flow statistics from nearby USGS gages).

4. 4 | Wind and Water Power Programeere.energy.gov Technical Approach The technical resource at the selected locations has been estimated accounting for water depth and velocity requirements, device spacing, and back effects. The recovery factor was found to be related to river properties (e.g., slope and flow rate) and it has been estimated for all of the significant US rivers allowing for an estimate of the technical hydrokinetic resource throughout. The integration of the NHDPlus data and the USGS flow statistics, the quantification of back effects by representing devices with an enhanced bottom roughness, and the development of the recovery factor are unique aspects of the approach.

5. 5 | Wind and Water Power Programeere.energy.gov Plan, Schedule, & Budget Schedule Initiation date: 1/1/2010 Planned completion date: 12/31/2011 Expert workshops (April 2010 and April 2011) Compile available energy resource data (complete) Determine technical resource (methodology complete, complete analysis November, 2011) Final Report (December 2011) Budget: No budget variances 66% of budget invoiced through 6/30/2011 Budget History FY2009FY2010FY2011 DOECost-shareDOECost-shareDOECost-share $81,613$121,541$102,451$24,657

6. 6 | Wind and Water Power Programeere.energy.gov Accomplishments and Results The most important technical accomplishments were: (a) the estimation of the theoretical resource in the major US rivers and the frequency distribution of that resource, (b) the theoretical work to estimate the “back effects” associated with In-Stream hydrokinetic devices, (c) the conduct of the case studies to determine the “recovery factor” in various settings, (d) the work to relate the recovery factor to available stream properties in our data base, and (e) the estimation of the technical resource in the major US rivers (using the recovery factor). In accomplishing these tasks, we have essentially reached all of the technical targets that we set out to reach. [Relate the accomplishments to project milestones, barriers, and objectives.] [Benchmark the accomplishments against the technical targets, if applicable.]

7. 7 | Wind and Water Power Programeere.energy.gov Accomplishments and Results Development and vetting of methodologies put the project on track to complete the assessment on schedule. Final results will be available in calendar year 2011.

8. 8 | Wind and Water Power Programeere.energy.gov Challenges to Date Significant challenges included the mass of data to be analyzed and synthesized, data limitations in some areas, and anomalies in the source data set. These challenges were addressed by extensive manual analysis of data, derivation of spatial extrapolation techniques, and documentation of methods and assumptions.

9. 9 | Wind and Water Power Programeere.energy.gov Next Steps Implementation of the vetted methodology will be completed in November, and the final report will be completed in December, 2011. Future research could include: rectification of data anomalies identified in the NHDPlus database more rigorous assessment of rivers identified as having relative high potential for energy production application of additional constraints to translate the technical resource to a practical resource (considering additional economic, social, and environmental constraints)