1. University of Washington, Mechanical Engineering
NW National Marine Renewable Energy Center
depts.washington.edu/nnmrec Site Characterization of Admiralty Inlet August 26, 2009
Brian Polagye
University of Washington, Mechanical Engineering

2. NNMREC Overview
Partnership between Oregon State University (Wave Energy) and University of Washington (Tidal Energy)
Funded by US Department of Energy, Oregon, Washington, and industry partners
Tidal energy research focused on four areas:
Site and device characterization
Device and array optimization
Environmental effects
Materials to improve survivability and reliability

3. NNMREC Mission
“Facilitate responsible device commercialization, inform regulatory and policy decisions, and close key gaps in understanding.”
Developing generally applicable tools and methodologies
For site and device characterization, using Snohomish PUD project as a test case for these tools and methodologies

4. Site and Device Characterization
J. Thomson (UW-APL) & B. Polagye (UW-ME)
R/V Jack Robertson
Field measurements (surveys + stationary) to inform:
Site developers: resource and site characteristics
Device developers: device performance
Regulators: near-field effects
010, ,TID

5. Stationary Measurements via “Sea Spider”
CTDO (conductivity, temperature, depth, dissolved oxygen – partnership with WA Dept of Ecology)
Acoustic release (redundant recovery)
ADCP
(Acoustic Doppler current profiler)
VEMCO recorder
(tagged fish species – partnership with NMFS)
Hydrophone (background noise)
T-POD recorder
(porpoise clicks)
Programmed for 3 month deployments
Lead Weight
(600 lbs)

6. Stationary Measurement of Tidal Currents
Power generation generally requires > 1 m/s
012, ,TID

7. Shipboard Survey of Tidal Currents

8. Shipboard Survey of Water Quality
In-situ measurements show slight halocline and thermocline (for this cast)
Lab results indicate low turbidity (for this season)
(WHO drinking water guidelines: < 1 NTU)
003, ,TID

9. Shipboard Survey of Fish Abundance
BioSonics echosounder (Center partner)
Significant cross-talk between echosounder, ADCP, and depth finder
Fish School?
Large Cobbles
Seabed return
006, ,TID

10. Shipboard Survey of Underwater Noise
004, ,TID

11. ROV Survey (video) of Seabed
Scoured seabed
Relatively flat
Cobbles and gravel
Sponges
Barnacles
Consistent with high currents and grab samples
005, ,TID