Northwest National Marine Renewable Energy Center

NW National Marine Renewable Energy Centerdepts.washington.edu/nnmrec

Site Characterization of Admiralty InletAugust 26, 2009

Brian PolagyeUniversity of Washington, Mechanical Engineering

Northwest National Marine Renewable Energy Center

• 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

NNMREC Overview

Northwest National Marine Renewable Energy Center

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

Northwest National Marine Renewable Energy Center010,04-23-09,TID

Site and Device Characterization

Field measurements (surveys + stationary) to inform:• Site developers: resource and site characteristics

• Device developers: device performance

• Regulators: near-field effects

R/V Jack Robertson

J. Thomson (UW-APL) & B. Polagye (UW-ME)

Northwest National Marine Renewable Energy Center

ADCP (Acoustic Doppler current profiler)

Lead Weight(600 lbs)

CTDO (conductivity, temperature, depth, dissolved oxygen –

partnership with WA Dept of Ecology)

Hydrophone (background noise)

T-POD recorder

(porpoise clicks)

Acoustic release (redundant recovery)

Programmed for 3 month deployments

VEMCO recorder(tagged fish species –

partnership with NMFS)

Stationary Measurements via “Sea Spider”

Northwest National Marine Renewable Energy Center012,04-23-09,TID

Stationary Measurement of Tidal Currents

Power generation generally requires > 1 m/s

Northwest National Marine Renewable Energy Center003,04-22-09,TID

Shipboard Survey of Tidal Currents

Northwest National Marine Renewable Energy Center

-70

-60

-50

-40

-30

-20

-10

0

0.00 0.20 0.40 0.60 0.80 1.00

Turbidity (NTU)

Dep

th (

m) Cast 1

Cast 2

Cast 3

Cast 4

Cast 5

003,04-22-09,TID

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)

Northwest National Marine Renewable Energy Center006,04-22-09,TID

Shipboard Survey of Fish Abundance

Seabed return

Large Cobbles

Fish School?

• BioSonics echosounder (Center partner)

• Significant cross-talk between echosounder, ADCP, and depth finder

Northwest National Marine Renewable Energy Center004,04-22-09,TID

Shipboard Survey of Underwater Noise

Northwest National Marine Renewable Energy Center005,04-22-09,TID

ROV Survey (video) of Seabed

• Scoured seabed• Relatively flat• Cobbles and gravel• Sponges• Barnacles

• Consistent with high currents and grab samples