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2016

  • AHERC
  • Hydrokinetic Energy
  • Yakutat Area Wave Resource Assessment
  • Tschetter, T., J. Kasper, and P. Duvoy
  • Publisher: Alaska Center for Energy and Power, Alaska Hydrokinetic Energy Research Center
  • Funding: Alaska Energy Authority, City and Borough of Yakutat

Yakutat is a community along the northeast coast of the Gulf of Alaska that is currently considering utilizing renewable, wave based electricity generation in order to lessen their reliance on diesel fuel for electricity generation. As part of this effort the University of Alaska Fairbanks carried out a study to assess the wave energy resource off of Yakutat’s Cannon Beach. Funding for the assessment was provided by the Alaska Energy Authority and the City and Borough of Yakutat. The study described herein utilized a combination of in situ observations and numerical modeling. The mean annual available wave energy at the mooring site is approximately 19.2 kW/m. While on an annual basis, this is less than sites off of Oregon or Hawaii (e.g. Kilcher, 2015), there is a large interannual variability in the Yakutat resource due to the frequent passage of storms over the Northern Gulf of Alaska. Winter values of the monthly mean available wave kinetic energy exceed 35 kW/m. Thus the resource is more than enough to satisfy Yakutat’s relatively modest electrical demand (e.g. Previsic and Bedard, 2009).

2015

  • AHERC
  • Hydrokinetic Energy
  • Debris Detection Methods
  • J.L. Kasper, J.B. Johnson, P.X. Duvoy, N. Konefal, J. Schmid
  • Funding: Northwest National Marine Renewable Energy Center

Debris in rivers and along coastlines occurs frequently. However very little quantitative information is available on the size, location, dynamics and most importantly the risk debris poses to river and marine energy converters. This report reviews techniques and instruments for quantifying debris, its potential for damaging marine hydrokinetic infrastructure and technologies that may be suitable for quantifying debris at prospective hydrokinetic energy sites. The different detection options discussed include mechanical, video and sonar technologies.

  • AHERC
  • Hydrokinetic Energy

Installation of hydrokinetic power-generating devices is currently being considered for the Yukon and Tanana rivers, two large and glacially turbid rivers in Alaska. We sampled downstream-migrating fish along the margins of both rivers, a middle island in the Yukon River, and mid-channel in the Tanana River in order to assess the temporal and spatial patterns of movement by resident and anadromous fishes and hence the potential for fish interactions with hydrokinetic devices. Results suggest that (1) river margins in the Yukon and Tanana rivers are primarily utilized by resident freshwater species, (2) the mid-channel is utilized by Pacific salmon Oncorhynchus spp. smolts, and (3) only Chum Salmon O. keta smolts utilize both river margin and mid-channel areas. Some species exhibited distinct peaks and trends in downstream migration timing, including Longnose Suckers Catostomus catostomus, whitefishes (Coregoninae), Arctic Grayling Thymallus arcticus, Lake Chub Couesius plumbeus, Chinook Salmon O. tshawytscha, Coho Salmon O. kisutch, and Chum Salmon. Due to their downstream migration behavior, Pacific salmon smolts out-migrating in May–July will have the greatest potential for interactions with hydrokinetic devices installed in mid-channel surface waters of the Yukon and Tanana rivers.

  • PSI
  • Power Systems Integration

Energy storage systems have the capability to provide viable reductions in the fuel consumption of diesel generators in islanded grids with medium to high penetration of renewable energy sources. Kinetic energy storages systems (KESS) can provide spinning reserve capacity (SRC) in such grids. This allows operating with a lower capacity of diesel generators to meet the same demand. This contribution utilizes the Specification, Design and Assessment Methodology (SDA) to develop a KESS and its operational strategy for the islanded grid of Nome, Alaska. The resulting reduction of the diesel consumption is determined through simulations. A possible secondary function of the KESS is to provide load smoothing which relieves the generators from high dynamic load changes.

  • AHERC
  • Hydrokinetic Energy

Installation of hydrokinetic power-generating devices is currently being considered for the Yukon and Tanana rivers, two large and glacially turbid rivers in Alaska. We sampled downstream-migrating fish along the margins of both rivers, a middle island in the Yukon River, and mid-channel in the Tanana River in order to assess the temporal and spatial patterns of movement by resident and anadromous fishes and hence the potential for fish interactions with hydrokinetic devices. Results suggest that (1) river margins in the Yukon and Tanana rivers are primarily utilized by resident freshwater species, (2) the mid-channel is utilized by Pacific salmon Oncorhynchus spp. smolts, and (3) only Chum Salmon O. keta smolts utilize both river margin and mid-channel areas. Some species exhibited distinct peaks and trends in downstream migration timing, including Longnose Suckers Catostomus catostomus, whitefishes (Coregoninae), Arctic Grayling Thymallus arcticus, Lake Chub Couesius plumbeus, Chinook Salmon O. tshawytscha, Coho Salmon O. kisutch, and Chum Salmon. Due to their downstream migration behavior, Pacific salmon smolts out-migrating in May–July will have the greatest potential for interactions with hydrokinetic devices installed in mid-channel surface waters of the Yukon and Tanana rivers.

  • Geothermal Energy

The Aleutian Pribilof Islands Association, the Alaska Center for Energy and Power, and the Alaska Energy Authority share an interest in geothermal utilization for district heating or other direct use applications to benefit communities. The purpose of this project was to assess opportunities for low-cost, non-power options for the direct use of hot spring geothermal energy, with an emphasis on district heating, to benefit the communities of Adak, Akutan and Atka.

  • AHERC
  • Hydrokinetic Energy

2013

  • AHERC
  • Hydro Energy

This report describes the results of a three-year study to characterize the river environment of the Tanana River at Nenana, Alaska, as it relates to the deployment and operation of hydrokinetic power generating devices (HKDs). Our particular interest was in determining those aspects of the river environment that may affect the infrastructure deployment and operations of HKDs and the effects of HKD operation on the river environment. A goal was to establish the Tanana River Test Site (TRTS) at Nenana to facilitate development and testing of HKD technology in a realistic Alaska river setting and develop methods of evaluating river hydrokinetic conditions, HKD performance parameters, and the economics of HKD power (Figure 7). The study site was initially identified by the Ocean Renewable Power Company (ORPC), which subsequently obtained a Federal Energy Regulatory Commission (FERC) preliminary permit to operate at the site. The ORPC approached the University of Alaska Fairbanks (UAF) Alaska Center for Energy and Power (ACEP) about a collaboration to conduct HKD-related studies of the Tanana River at Nenana. This collaboration led to the creation of the Alaska Hydrokinetic Energy Research Center (AHERC) and the start of this project, which was supported by the Alaska Energy Authority’s (AEA) Renewable Energy Fund.

  • PSI
  • Power Systems Integration

This case study investigates the first cold climate use of an Organic Rankine Cycle (ORC) machine coupled with a diesel generator as integrated by the Cordova Electric Cooperative. The goal was to generate extra electricity from waste heat from a diesel generator in order to increase the fuel efficiency of the generator by generating extra electrical power.This case study investigates the first cold climate use of an Organic Rankine Cycle

2011

  • Geothermal Energy

Small-scale biogas digesters are commonly used throughout regions with tropical and subtropical climates: Southeast Asia, Central and South America, the Middle East, and Africa. Digesters are used to generate biogas, which is a mixture of methane, carbon dioxide, and other trace gases. Biogas can be used as a fuel for a number of different applications including cooking, heating, and running an electric generator. Typically, the methanogens responsible for biogas production are limited in application to warm environments. This project, which was funded by the Denali Commission Emerging Energy Technology Grant (EETG) program, investigated the development of biogas digesters in cold climates using recently discovered psychrophilic (cold loving) methanogens. The following report includes a project summary, a discussion of challenges, and recommendations for future projects and research

  • Geothermal Energy

As fossil fuel resources are depleted across the globe, Alaskans are hard-hit in the search for energy. Northern households are especially dependent on gas for heating and transportation. As fuel prices rise, Alaskans, and rural Alaskans in particular, face some of the highest fuel prices in the country. These economic stresses threaten Alaskan livelihoods, while political pressures threaten the state‟s landscape and wildlife in a push for increased drilling and risky fuel transportation. Renewable energy offers the opportunity for communities to harvest natural fuel from unlimited sources. Solar power, wind energy, and hydroelectric are becoming increasingly common as Alaskans seek independence from fossil fuels. Funding for research and development of efficient renewables is on the rise as economic and political pressures increase. Biogas energy is a relatively simple technology that has been in use around the world for decades. With funding from the Denali Commission Emerging Technology Grant, a collaboration of scientists, engineers, and teachers has advanced digester technology for use in the north. These cold-adapted digesters, engineered for small-scale household use, allow individuals to uniquely contribute to offsetting their fuel costs and waste output. This booklet was written as a resource for Alaskans and other northern communities interested in biogas technology. Included is the history and science behind digesters, a detailed construction manual and troubleshooting section, and a description of the challenges and benefits of biogas. With this information, we hope to encourage the further development of biogas digesters as a mainstay of Alaska‟s renewable energy resources.

  • Geothermal Energy

The primary objective of the Phase I study was to determine the optimal gas production rate at which small-scale psychrophilic digestors could be expected to perform within Alaskan climates and to compare biogas production efficiency under these conditions with that commonly observed in the tropics, where digestors are a mainstream form of energy production. In Phase I, six different digestor vessels (incubated at 15°C and 25°C) were fitted with data logging devices, gas collection systems and were kept within a semi-temperature controlled environment to test the effects of temperature on the various microbial consortia (mesophiles vs. psychrophiles) within the reactors. We monitored the following variables throughout the study: room and digestor temperatures, dissolved oxygen, pH, gas composition, flammability, and gas production rates. Using a feeding or loading rate of 2kg of substrate per day (1:1 food and water), researchers aimed to determine how close coldtemperature biogas production by psychrophiles, mesophiles and mixed cultures could come to the efficiency observed with small-scale warm-temperature biogas production in India, which is approximated at 500g CH4 (around 800 Liters or 28 cubic feet @ 30°C) per day (Karve, A.D., 2 2011). Currently, our highest sustainable production based on only 1 kg of food substrate (dry weight) per day is <140g of CH4 or 230L/day, which is roughly 30% warm-climate digestor efficiency of comparable digestors in India. The maximum biogas production rate observed on a single day at any point during this study was 433 L/day. Results from Phase 1 supported our initial hypotheses. We found that biogas production was higher at 25°C than at 15°C, and that cold-tolerant microbial populations derived from thermokarst lake sediments produced more biogas than warm-loving manure-derived microbes at low temperatures.

  • Geothermal Energy

Phase 1 of this project is defined by experimentation with a variety of microbial communities (psychrophiles, mesophiles, and mixed communities) and temperature conditions (15 °C and 25 °C), and as such is the heart of the development stage for this proposal. As this is a unique approach to the development of a cold-adapted digester, we are facing a variety of interesting challenges in bringing the experimental systems to optimal gas output. The continual benefit of this process is developing an extensive database of fundamental data on the chemical processes and gas output of this biologically-based technology, while testing the physically-engineered aspects of the constructed systems.

  • Power Systems Integration

The results of the Factory Acceptance Test are somewhat mixed, and can be summarized as follows: • The Transflow 2000 unit was assembled, complete, and operating at the FAT on July 18-22, 2001 • Communications with the battery through the internet were possible through a web page interface. • Baseline data on performance was collected. • The battery did not demonstrate the expected energy storage capacity of 2.8 MW-hrs, instead providing only about 1.6 MW-hours of DC power. • In multiple tests, the efficiency of the battery varied considerably, for unknown reasons. If this were a commercial utility purchase of a standard product, the responsible action would be to decline acceptance of the unit based on a failure to perform to expected levels. However, this project at Kotzebue Electric Association is funded largely through funds intended to demonstrate pre-commercial technologies and evaluate their possible use in Alaskan communities. The objective of the project is to test the hardware and assess its level of performance.

2010

  • Geothermal Energy

In 
the
 spring
 of
 2010, 
WHPacific geologist 
Steve 
Buckley, 
ACEP/UAF
 geology 
student 
Peter 
Illig
 and 
WH
Pacific 
Engineer 
Matt 
Bergan 
conducted 
a 
study 
of 
Division 
hot
 springs 
south 
of
 the 
villages 
of
 Shungnak 
and 
Kobuk 
and 
located 
within 
the
 Division
 National
 Wildlife
 Refuge.
 The 
goal
 was 
to 
gather 
base line
 physical
 data
 on
 the
 Division 
hot springs
and 
determine
 the
 potential 
for
 geothermal 
power
 production 
that
 could
 aid 
the
 rising 
energy 
costs 
of
 the
 surrounding
 communities.


  • Power Systems Integration

This report investigates the installation of a zinc-bromine flow battery system at Kotzebue. There is much interest in this technology for Alaska given the challenges of integrating intermittent energy sources into the many microgrids prevalent throughout rural Alaska. This report identifies the project participants and their roles and documents the development of the project, performance of the battery system factory acceptance test prior to shipment, and the installation and subsequent operational experience in Kotzebue. The report also presents findings based on the experience in the field, makes recommendations for the future direction of the flow battery project at Kotzebue and presents broader recommendations for other, future battery projects in Alaska communities.

  • Wind Energy

This initial report gives a review of technologies that are suitable for communities in Alaska that are operating wind-diesel hybrid systems, including aspects such as power electronics, energy storage, and control strategies. Additionally, key research questions are developed as well as testing protocols and experiment specifics, based on final equipment selection for the test bed.

2009

  • Other
  • Geothermal Energy

Although it is possible that most or all of the known thermal springs in the NANA region might be theoretically capable of supporting direct use or small scale power generation projects like the one installed at Chena Hot Springs in 2006, the Granite Mountain Hot Spring, along with Division Hot Springs were identified in the GAP Report as being the two most attractive hot spring sites for additional geothermal exploration effort.

  • Data Collections and Analysis

The purpose of this project was to assist TDX with obtaining data from existing water wells at Manley Hot Springs. There are numerous water wells that have been drilled over the years at Manley Hot Springs, but only four wells are on file in the State records and few data are available. The goal was to use standard geothermal pressure and temperature logging tools to obtain well data from any accessible water wells in the area. If wells were not accessible, a flowing temperature was obtained if possible.

  • Technology and Resource Assessments

The basic concept examined in this evaluation is to employ heat pumps to “lift” latent heat from raw seawater at temperatures ranging from 35F to 55F, and transfer this heat energy into air handler units and pavement at a temperature of 120F. The air handler units AHU-5 and AHU-6 are roof level units that currently transfer heat from a boiler fired 185F glycol loop in to the supply air stream for the building. Both units are equipped with duct coils through which a mixture of outside air and return air is drawn. The rate of glycol supply to these duct coils is modulated to maintain a temperature of 55F through 70F air leaving the air handler. The total design demand of AHU-5 plus AHU-6 is 3,124 MBH (3,124,000 BTU/hour) which represents approximately 40% of the total facility design heating demand. Accordingly, installation of heat pumps to supplement a majority of the heating demand for AHU-5 and AHU-6 will translate to significant reduction of heating oil usage and monthly operational costs.

  • Wind Energy

Diesel-off hybrid power systems represent the next generation wind diesel systems. In traditional systems, the diesel gen-set regulates both the voltage and frequency of the grid. In order to maximize fuel savings, it is desirable to be able to operate the system with the diesel engines shut off when other renewable power sources, such as wind, are available. However, in order to do so power electronics must be advanced enough to meet the power quality needs for the grid and customers. The Alaska Center for Energy and Power proposes to analyze state of the art power electronics to assess options for operating in a diesel-off mode. The review will be broad to incorporate both a systemic analysis of diesel-off technology as well as a component analysis, which will look in depth at flywheel, energy storage, and inverter dynamics. The project will be completed through the Wind Diesel Application Center (WiDAC), which is managed and operated as a consortium of industry and private sector partners involved in the development of wind-diesel systems in Alaska.

  • Technology and Resource Assessments

This report presents the results of Polarconsult's review and analysis of the technical feasibility, economic feasibility, challenges and advantages of using high-voltage direct current (HVDC) electrical interties to connect remote Alaska communities with each other and with local energy resources.

2008

  • Other
  • Data Collections and Analysis

While this report represents the most comprehensive effort to date to quantify GHG emissions within the FNSB, there are clear limitations involved. Accounting for all the aggregate emissions generated in our daily lives is a nearly impossible task, and there is no current methodology for capturing the emissions associated with all the imported goods coming into a community. As such, the scope of this inventory is limited to the major source categories of transportation, heating, electric energy production, and solid waste, which is consistent with inventories that other ICLEI communities have undertaken.

  • Biomass Energy

One major issue with the use of biodiesel fuels is the propensity of these fuels to oxidize during storage and form lacquers, resulting in failure of fuel handling systems. During one season of testing of a fish oil biodiesel in Alaska, a total of six out of six engines failed, all caused by fuel system seizures from lacquer films from partially oxidized fish oil. In retrospect, the oxidation of the biodiesel was due to the lack of understanding by the test program participants of the need for anti-oxidant additives, and for the proper storage conditions and time. This raises the question of the possibility of rehabilitating fuel that has undergone oxidation sufficient to render the fuel questionable. Preliminary tests at the UAF diesel test bed indicate that oxidized fish oil biodiesel can be rehabilitated and used as a fuel in diesel engines.

  • Power Systems Integration

In recent months, many interested persons have asked a variety of questions about the proposed HVDC system for rural Alaska. To increase understanding of the proposed project, system and technology, we have prepared this compilation of questions and answers about the project. This compilation provides more detail about the information highlighted in our HVDC White Paper. They are written for those that wish to better understand the HVDC technology and its benefits.

2007

  • Data Collections and Analysis

On September 14th, 2007, the Fairbanks North Star Borough (FNSB) Assembly passed Resolution 2007-40 (see Appendix C), which committed the Borough to participate in the International Council for Local Environmental Initiatives (ICLEI). To date, more than 200 local governments across the U.S. and 770 local governments worldwide have joined ICLEI under their Cities for Climate Protection (CCP) Campaign in order to proactively address greenhouse gas emissions within their communities. In Alaska, the communities of Anchorage, Homer, Juneau, and Kodiak also participate in the program. As a signatory to ICLEI, the FNSB agreed to participate in a five-milestone process to develop an action plan which includes goals and targets for combating climate change and greenhouse gas emissions in the Borough. These milestones include:

2002

  • Wind Energy

This document represents the first chapter in the Operations and Maintenance Manual for the Wales Wind-Diesel Hybrid Power System. The entire manual is organized into many chapters with multiple appendices, totaling hundreds of pages, most of which are quite specific to the Wales system and not of general interest. The entire manual will therefore be produced in only a limited number of copies for those individuals and organizations with a direct role in operating and maintaining the system. The first chapter of the manual, however, deals with the system theory of operation, which is of more general interest, and is being published as this National Renewable Energy Laboratory (NREL) Technical Report. This report will also serve as a record, in summary fashion, of the hardware and software hybrid system controls technology developed by NREL under the Wales project. The authors intend that it be used as a reference not only by those directly involved in the operation of the Wales system, but by anyone with an interest in high-penetration, wind-diesel hybrid technology.

  • Wind Energy

2001

  • Wind Energy

Most of the engineering effort on the Wales project focused on the design and development of the new system components, primarily the main system controller and the energy storage subsystem. Comparatively little attention was paid to the diesel plant itself and to the modifications necessary to successfully integrate it into a fully automated wind-diesel hybrid system. Consequently, many diesel plant shortcomings were overlooked until they manifested themselves in the field during the start-up and commissioning of the wind-diesel hybrid system. The resulting problems revealed that in such a system, the diesel plant must perform to a higher 2 standard of performance than is often expected of the typical village power plant, which is usually designed to be completely manually operated. These higher performance requirements necessitate more rigorously designed diesel plants. Design shortcomings were found in all of the major diesel plant subsystems (engine cooling and fuel systems, generators, controls, switchgear, and distribution system).

2000

  • Wind Energy

Batteries are often used in wind-hybrid systems to store excess wind energy and then provide supplementary energy when the wind cannot generate sufficient power to meet the electric load. A battery monitoring system is therefore needed to track and display battery usage characteristics, and to estimate and detect trends in battery state-of-charge (SOC). From these measurements the state-of-health (SOH) of the battery can be estimated. However most commercial monitoring systems are designed for batteries that are used for other applications, and thus a more suitable battery monitoring system for wind-hybrid systems is needed. Such a system was created, using a Direct Logic 250 Programmable Logic Controller (PLC). The PLC was programmed to log, manipulate and conveniently store the battery bank DC voltage, the DC current of each battery string, and the temperature at up to 4 different locations on the battery bank. When the battery is fully charged, the PLC takes a DC resistance measurement, which is compared with previous measurements to determine the approximate SOH of the battery. A Quickpanel touchscreen was then programmed to display the data from the PLC, as well as to provide an interface for user input to the PLC. The hardware was then tested with simulated inputs to ensure a working battery monitor had been constructed, that can now be fully assembled and tested on an actual battery bank that is subject to charge cycling.