ACEP -Alaska Center for Energy & Power

M. J. Murdock Foundation - Building Capacity at the Tanana River Test Site

The M. J. Murdock Charitable Trust funded the University of Alaska Fairbanks to customize a research vessel and purchase a variety of mobile instrumentation to measure river and ocean bathymetry, water velocity and turbulence, sediment transport, debris flow, fish behavior and habitat, and river- and sea-bed geology. The vessel serves as an integrated platform for new Murdock Trust-funded instrumentation as well as for existing instrumentation. The new instrumentation enhance UAF’s capability to make hydrologic and oceanographic measurements nationally as well as internationally.

Project Background   

Generation of electric power from water currents produced by tides and rivers (hydrokinetic energy) has recently received an upswell in interest both in Alaska and nationally.  As a renewable resource, hydrokinetic energy could reduce greenhouse gas emissions, reduce energy costs in rural villages, and utilize Alaska’s abundant tidal and river current energy. In fact, Alaska has approximately 40% of the total river energy, approximately 90% of the total tidal energy and approximately 60% of the total wave energy in the United States.  Especially due to the high cost of power in Alaska, many communities are considering whether accessing these hydrokinetic energy resources to generate electric power is economically feasible and environmentally sustainable.

Project Description

In 2013, the Murdock Trust funded the customization of an existing pontoon barge and the purchase of instruments to expand UAF’s ability to conduct base-line studies of river and ocean environments as related to the placement of hydrokinetic energy devices (HKD) into fresh and salt water bodies. The barge was donated to UAF by Alaska Power and Telephone (AP&T) at the conclusion of a Denali Commission/Alaska Energy Authority-funded demonstration project carried out on the Yukon River near Eagle, AK. As part of the AP&T project, the barge served as the platform for deploying a 25 kW New Energy “Encurrent” hydrokinetic turbine. Over the course of the UAF Murdock Trust project, the pontoon’s base was widened in order to increase its carrying capacity and stability, and numerous winches, davit wells and a hydraulic capstan were added to it. The modified barge was first deployed in Fall 2014 to support the testing of an Oceana Energy, Inc. turbine in Nenana, AK. Once the project is completed in Summer 2015, the customized pontoon barge will serve as a platform to deploy and recover hydrokinetic infrastructure, conduct fish studies and provide a stable platform for instrumentation to monitor hydrodynamic changes that may affect HKD operation.

During winter 2014/15, the barge is being outfitted with reinforcements for handling nets for fisheries studies. In addition, multiple hydraulic winches will be added to increase the flexibility of the barge in serving as a hydrokinetic test and monitoring platform. A separate “pusher” boat is being outfitted to maneuver the barge on Alaska’s swift and turbulent rivers. The pusher boat will be able to accommodate existing UAF instrumentation, such as sonar systems and GPS receivers, and it will also provide a stable survey vessel for carrying out hydrographic surveys with Murdock Trust-funded instrumentation.

Upon completion of the Murdock Trust project in 2015, the barge and pusher boat system, along with new and existing sonars, acoustic cameras and traditional fish capture gear, will enable unique fisheries studies in Alaska’s rivers. The sonar gear will support research on salmon migrations and fish behavior in relation to river hydrology, studies that were previously impossible in Alaska’s large glacial rivers. Trawl nets and a “fish trap” will be used to understand how fish species vary with time and location in the river, and whether HKDs harm salmon smolt. All of these are important considerations when contemplating anthropogenic modification of rivers and oceans.

The Reson multibeam sonar will allow for critical repeat bathymetric measurements at both the TRTS and in more remote locales. Repeat bathymetric surveys are one way to determine how river depth may change with changes in river stage and also can provide an indication of whether HKD operation may be impacted by—or have an impact on—riverbed morphology and bottom habitat. Such surveys are also useful for quantifying sea and river bed debris.

Overall, new Murdock Trust-funded equipment combined with existing instrumentation and capabilities will will support major Alaskan research priorities, such as how energy production from river, tidal currents and waves may affect state fisheries. It will enable UAF to carry out unique in-river hydrokinetic research in challenging Alaskan environments.

Photo 1: Research debris diversion platform with the Murdock Trust funded pontoon research barge tethered downstream. An instrument shelter and Oceana turbine are visible on the deck of the barge.  Photo courtesy P. Duvoy, ACEP/UAF.

Photo 2: From left, AHERC Program Director Jeremy Kasper, Research Engineer Jack Schmid, Student Intern Timothy Tschetter, Senior Research Advisor to AHERC Jerome Johnson, and Student Intern Jeff Roba standing on the Tanana River Test Site barge prior to launch.  Photo courtesy of T. Paris UAF.

Figure 1. Research Vessel Schematic.  Courtesy of J. Kasper, AHERC/UAF.