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NORTHERN ENGINEER a Publication of the School of Engineering THE NORTHERN ENGINEER a publication of the school of engineering ""-·, • •• 4/ltlll .. Volume 23, Number 2 & 3 u NIVERSilY OF ALASKA FAIRBANKS .. Summer/Fall 1991 ADVISORY BOARD e are a reflection of our times. For THE NOKTHERN W ENGINEER, the University of Alaska, the State of Alaska, the Robert Boswell Lake & Boswell United States ofAmerica, and even the world as a whole, this is a time Fairbanks, AK of transition. The University of Alaska Fairbanks, of which THE AndrieChen NOKTHERN ENGINEER is a part, is undergoing a reorganization with Exxon Production the intent being to create a more streamlined, stronger entity, better Research Company Houston, TX able to meet the needs of our many constituencies. Mark Fryer Fryer/Pressley How will these changes affect THE NOKTHERN ENGINEER? Engineering, Inc. Anchorage, AK Well, one change has already occurred, Cynthia M. Owen left the Wilbur Haas University ofAlaska Fairbanks, effective June 30, 1992. This is the last Michigan Technological University issue that Mrs. Owen collaborated on--editing, proofing, Houghton, MI brainstorming. She contributed greatly to the quality of this publication Lee Leonard and will be sorely missed. U.S. Department of Energy Washington, DC The next part of this change will be the need for us to address the problems of THE NOKTHERN ENGINEER. We have been facing a Ed Link U.S.CRREL decline in paid subscribers, dijficulty in obtaining publishable technical Hanover,NH material and severe budgetary constraints. For all of these reasons, MikeMetz THE NORTHERN ENGINEER will temporarily suspend publication, Yukon Pacific Corporation effective the Winter 1991/Spring 1992 issue. During our suspension, we Anchorage, AK will explore alternative ways to successfully restructure the magazine N.R. Morgenstern and would welcome any of your comments and ideas on how to make University of Alberta THE NORTHERN ENGINEER better and stronger. Edmonton, Alberta, Canada J.F. ''Derik" Nixon Nixon Geotech Ltd. Calgary, Alberta, Canada Stephanie Brower Ted Vinson Editorial Staff Oregon State University Corvallis, OR 2 THE NORTHERN ENGINEER, VOL. 23, NO. 2&3 THE NORTHERN ENGINEER a publication of the school of engineering Volume 23, Number 2&3 Summer/Falll991 IN THIS ISSUE ••. FACULTY ADVISORS Some Electric Utility Problems in Rural Alaska: F. Lawrence Bennett Service Quality and Metering Engineering & Science Whitham D. Reeve, P.E........................................................................... 4 Management Ice Island Construction With Ice-Water Mixtures Douglas L. Kane T.W. Forest, K. Szilder and E.P. Lozowski ........................................... 19 Water Resources & Civil Engineering A Passive Radiator for a Refrigerated Terry T. McFadden Foundation on Permafrost Mechanical & Arctic Engineering R. Bhargava, P.E., D. Bassler, P.E. and J. Patterson, P.E...................... 28 Robert P. Merritt Telecommunications in Rural Alaska Electrical Engineering Part ll-Transmission Systems Will Nelson Whitham D. Reeve, P.E......................................................................... 34 Mechanical & Arctic Engineering Back of the Book .............................................................................................. 51 Rossen Ostermann Petroleum Engineering Conversion Factors ......................................................................................... 59 LutfiRaad Transportation & Civil Engineering THE NORTHERN ENGINEER would like to thank Dr. Robert Speck Charlie Mayer, Electrical Engineering, and Dr. John P. Zarling, Mining & Geological Mechanical Engineering, for reviewing the articles included in Engineering this issue. EDITORIAL STAFF COVER________________________________________ ___ Cynthia M. Owen The cover graphic is from Whit Reeve's article about telecommunications Stephanie L. Brower in rural Alaska, beginning on page 34. THE NORTHERN ENGINEER (ISSN 0029·3083) Is a quarterly publication of the School ofEngfileering, University of Alaska Fairbanks. The magazine focuses on engineering practice and technological developments In cold regions, but In the broadest sense, Including articles stemming from the physical, biological, and behavioral sciences. It also includes views and comments having a social or political thrust, so long as the viewpoint relates to technical problems or northern habitation, commerce, development or the environment. Opinions in the letters, reviews, and articles are those of the authors and not necessarily those of the University of Alaska, the School of Engineering, or THE NORTHERN ENGINEER staff and board. Address all correspondence to THE NORTHERN ENGINEER, SCHOOL OF ENGINEERING, UNIVERSITY OF ALASKA FAIRBANKS, FAIRBANKS, ALASKA 99775-0660, USA. Subscription price: one year, $15; two years, $28; back Issues, $4 (US$ only please). The University of Alaska Is an EO/AA employer and educational institution. THE NORTHERN ENGINEER, VOL. 23, NO. 2&3 3 Some Electric Utility Problems in Rural Alaska: Service Quality and Metering by Whitham D. Reeve, P.E. Editor's note: This article is not one of Mr. Reeve's four-part Service quality problems can manifest themselves in terms telecommunications series; it is a separate effort which should of an annoying light flicker, a relatively high failure rate of be ofparticular interest to rural electric utility operators. incandescent light bulbs, and problems with personal and busi­ ness computers and other sensitive electronic devices such as INTRODUCTION VCRs, television sets and audio high fidelity equipment. At the This artiCle is for electrical engineers and others interested in very least, electric clocks will not run accurately. Many people solving some of the electrical utility problems common in rural are convinced that power disturbances can cause metering er­ Alaska. I will describe my observations, conclusions, and solu­ rors, too, but this is not the case. tions to these problems; the solutions are not necessarily unique, Electric utilities are capital intensive, especially in rural but they may spark insight in others facing similar situations. Alaska where costs for everything are high. Consequently, the I owned and operated a consulting electrical engineering invested cost per connected consumer is very high. The electric­ practice for 14 years. During that time, I was frequently called ity rates, in turn, must also be high for capital and operational to investigate electric utility metering and service quality prob­ cost recovery. Operational costs, such as for fuel, are ever lems all over Alaska, particularly in the Bristol Bay, Aleutian increasing, meaning the rates must increase. As rates increase, Islands, Alaska Peninsula, and Prince William Sound areas. consumers consciously lower their electricity use. Since much Through this work, I have acquired special expertise in solving of the utility costs are fixed, the unit electricity rate must rise. these power problems, mostly learning the hard way. Higher rates mean yet lower electricity use, and so on, until equilibrium or economic failure. PROBLEMS IN GENERAL A person moving into rural Alaska from an area with com­ paratively low electric rates is always shocked when the first Rural Alaskan communities have somewhat unique electri­ bill arrives. This usually sets off a long-running dispute between cal characteristics compared to urban areas. Almost all have the utility and the consumer about the accuracy of the con­ very large variations in load and demand factors between sum­ sumer's electric meter. The situation is usually_ resolved when mer and winter seasons. Many coastal communities have sea­ the "new" consumer becomes an "old" consumer; that is, the food processing plants that place a large seasonal load on the consumer learns how to make better use of electricity, which electric utility distribution and generation systems. Such plants lowers the bill. When rates are high, consumers can be very have large electric motors and the attendant voltage and wave­ frugal in their electricity use. Nevertheless, metering complaints form control problems that go with them. still and always will persist Diesel-electric generators are used almost exclusively in ru­ Table 1 shows representative electricity rates for various ral communities. By their very nature and location, it is impos­ communities in rural Alaska as compared to the urban areas­ sible to design, build, operate, and maintain power systems in Anchorage, Fairbanks, and Juneau. The State of Alaska pres­ such a way that they are free of power disturbances or degrada­ ently has a subsidy program called Power Cost Equalization tion in service quality, at least for short terms. In many commu­ (PCE) that attempts to provide rural electricity consumers with nities, good grounding systems-essential to reliable and rates that are comparable to urban areas, at least for the first troublefree electric utility operation-are difficult, if not impos­ 750 kiloWatthours (kWh) of consumption. The futrire of this sible, to obtain. 4 THE NORTHERN ENGINEER, VOL. 23, NO. 2&3 program is uncertain, as are all government funded subsidy good starting point. I will discuss how each of these, as well as programs. voltage unbalance in 3-Phase systems, affects service quality. VOLTAGE TABLEl. A COMPARISON OF TYPICAL RURAL ELECTRICITY RA1ES All electric utilities, by their nature, are obligated to deliver industry standard voltages as specified in ANSI C84.1-1982, Average PCE American National Standard for Electric Power Systems and Usage Electricity* Credit Location
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