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HomeMy WebLinkAboutGene Richard's Appropriate Technology Report, Burro CreekAppropriate Technology Report Hydroelectric System at Burro Creek Farms, Inc. Skagway, Alaska This report supplements our final hydroelectric report submitted earlier to the Department of Energy, a copy of which was submitted to the Alaska Division of Energy and Power Development. The format for this report covers the subjects listed in your letter of October 14, 1983. I LOCATION Burro Creek Salmon Hatchery is located 1.5 miles S.W. of Skagway,Alaska. (Lat. 590 26'N, Longitude 1350 22'W). Access across Taiya Inlet from Skagway is by boat only. The population of Skagway varies from about 600 in the winter to 2000 in the summer. The Klondike Highway provides road access to Skagway and is generally kept open from April through October. Air and water transpor- tation are available throughout the year. White Pass and Yukon Railroad provided rail transportation to Whitehorse, Canada but it was discontinued in 1982. It is unknown whether it will resume operations in the near future. The Alaska Marine Hiway System operates ferries between Skagway and other Southeast Alaskan cities, Prince Rupert, Canada, and Seattle, Washington on a regular schedule throughout the year. Cruise ships make over one hundred port -calls at Skagway during the summer months. Westours runs a day cruise boat -daily to the vicinity of Juneau from May to September. Alaska Power & Telephone Cho. provides Skagway with energy and Communica- tion services but does not include outlying communities of Dyes, and Burro Creek. Power generation is by diesels in the winter and a combination of diesel and hydra for the remainder of the year. The possibility of selling power from Burro Creek is remote due to the high cost of providing an under water cable across Taiya Inlet. At the time of this writing, diesel oil sells at the Skagway Bulk Plant at $1.109/ga1, No. 1 and $0.989/gal No. 2 and residential power costs about 17 to 20 ¢1KW depending on consumption. Telephone service and cable TV is available in Skagway but not at Burro Creek. We receive State TV on channel 13 and educational TV on channel 11 over the air. Water, sewer and garbage service is provided by the City of Skagway but not to Burro Creek, even though we are in the city limits. We have an air -jet sewer system which also includes a drain field. Our domestic water gravitates to the house from two independent water systems. The hatchery water source provides water through a 6" PVC pipe from the top of the creek's first waterfall (700' distance) at 20 PSI. The second supply is from the hydroelectric system which picks up water at the top of the third waterfall (1400' distance) and delivers at 90 PSI which is then reduced to 45 PSI. 11 l.L1Prn .... The National Weather Service of NOAA has recorded weather statistics at Skagway for many years and they are available on request. We have experi- enced temperatures from about -100 F to 800 F during the five years we have lived at Burro Creek. Surface ice forms on the Dyea tide flats in the winter and the prevailing North winds push them on our beach and into our tidal lagoon, particularly, during tides of maximum range. It is samilmes 6" thick but never remains long, as the wind and tidal currents keep it moving. The ice threat does preclude leaving a float or mooring in the water during winter months. We have our own marine railroad to pull our small boats out of the danger and a float is maintained by Westou from May thru September commensing i-i 1983. They conduct harbor tours to the hatchery during the summer months. About 3000 tourists inspected our hatchery and power system last year. Burro Creek flows year around and in reduced amounts under the ice during winter months. It drains 11.4 sqs miles of valley. Rainfall averages 22.49"/ year, most of which falls in August through October. III SYSTEM DESIGN It was originally planned to operate a 25 KW two -runner Peltech with two jets on each runner from a water source 1000 feet upstream with a head of about 150 feet. A subsequent survey made when the unit was under manu- facture, disclosed that it would be easier to pick up water at the top of the third falls, 1400' above the power house, with an increased head of ° 200 feet. The manufacturer redesigned the belt -drive system and plugged two of the four jets as they were unnecessary to generate 25 We This gives us an option to increase to 50 KW if a need arises, but we will have to replace the Lima alternator and probably change the belt -drive. The alternator selected was a Lima brushless, 25 KW, 3 phase 220 volt AC It was assumed that a large portion of the load would be used to drive motors on refrigeration compressors. Refrigeration is needed to process harvested fish to pay hatchery expenses. The pipeline between the'pewer house and the water source is a 10 inch diameter Simpson Twin -Seal PVC pipe designed for 125 PSI. (See also Final Technical Report on Hydroelectric System submitted to D.O.E.). IV CONSTRUCTION AND INSTALLATION The planning, purchasing and construction for this project was conducte� over a five-year period. It was given secondary pz•iority to the hatches construction which was done simultaneously. Most of one construction season (1982) was lost when Alaska Fish and Game ordered us to install i separate dam to furnish gravity water to the hatchery rather than use a siphon system or face cancellation of our hatchery permits. r The lack of road access to Burro Creek complicated delivery of pipe, pelton wheel, alternator, and associated supplies. Delivery was made possible by using the owner's 56' LCM landing craft. However, shipping AolnvR from Seattle and high associated costs were other important - V...•. ,.•.v .c, a:vuea wue our iirsL pnase, it wa3 built of cedar logs from the Queen Charlotte Islands ofi British Columbia. A skilled craftsman precut and assembled it at Masset. It was disassembled upon comp'_etion and loaded on a trailer for shipment to Prince Rupert by barge and ferry to Y.etchikan. At this pcin. it was trans "erred from the trailer to Lur landing craft for deliver;, to Burro Creek. The power house served as our taaporary home until we could complete the log residence in 1982. An air-cooled Lister Diesel that drives a 12 KW Lima brushless Llternator was installed on tha porch. It served as our prime enerTj source a:d will provide power when the hydroelectric system is shut down for tie winter or repairs. After the residence was complEted far enough to be cceupied, the power house was then available for installation of the Peltech and associated electrical distribution equipment. Simultaneously we started the pipe- line installation. First, -41%e right-of-way was cleared and pipe distribute( along the line. This required the use of a highline up the steep bluff at the bottom and zk.,n by trail bike or 3 ii-wheel drive coot on the more gradual slopes. The coot required additional clearinC to build a track rcad, When we built the filter box at the top of the line at the end of' the construction period we used a Welsh pony to drag t':e 16 foot 2x10's to the top. If we were to do it all over again, we would probably make more use of the pony. This would have reduced all road building and ex- penses involved in repairing mechanical equipment. � Tiie pipeline was assembled in sections from the bottom 1p to where a large change in %trade or direction required the fabrication of a special bend. Then it was a two or three week wait for the bend to arrive. It would s em that we could have laid it out with string and determine what our total requirements for special bends would be at one time. However, we never knew exactly how much change we could accomodate within the individual pi,,e joints until they were all assembled. We wanted to keep the number of special bends to a minimum ab they cost over $100 each. One ditch required digging at the top of the line. A little blasting of rock dus required and was done at the same time we blasted a notch out of the sill at Lhe top of the waterfall. The WP&Y RR rented us their Swedish built g:.s-driven hammer for the rock drilling operation. Bracing and s:curing the pipeline was the most time consuming :)rsration. Basically we used 1�4" aircraft cable for ties to expansion bolts set in bedrock or lame boulders. Drilling for the expansion sleeves was acccm- plished with a Milwau::ee electric rotary hammer driven by a portable 317 KW Pincor gas generator. The cable was secured to the pipe with cable clips. The pipe was first wrapped with building paper, aluminum flashing and then with used firehose at each tie point. This gave a good grip on the pipe and provided ample chafing gear. The cable ran throrgh the center of t.e firehose and was tig:.tened with turnbuckles. The cross - ties were supplemented with down -hill ties at 200 to 300 foot intervals to prevent the pipe from crawling down the hil'. One eye -bolt broke during a static test and the pipe blew apart at a joint. It was corected by replacing the pot -metal eye -bolt with a steel lag screw and by adding more ties. No further problems of this type occurred. The pipe rests oi: the ground as much as possible, but where changes in grade reeuired, a treated 6x8 e;upportin3 post was a�.cied at not more than JI ,� f _;, � � _ r .. #T Y.-, . .� ri3� uuu owv cx.iv CneeKa naliec to the top to serve a saddle. The bottom of the post was placed on bedrock or flat rocks. Special concrete anchors were provided at the bottom of the pipeline ov the last 80 feet. The mass of concrete proved to be inadequate to real movement at the very bottom so another yard of concrete was added plus similar size deadman on the bisector of the bend. This addition proved adequate plus it also stopped a small leak that had developed in a glue joint on the "T". The wood filter box was an after=thought. The purpose was to simplify water pick-up and to provide means of separating out debris and sedimen It included an overflow to assist in by-passing as much floating materi as possible and a catch basin to collect the sediment. 1-inch and z-in metal screens from a rock crusher were installed to filter out anything over i-inch. This turned out to be a mistake as ice generated rapidly on the metal screens in freezing weather. V OPERATION We had two months of continuous operation prior to the winter shut -down, bearing problem developed simultaeous with the advent of freezing weathe However, it was very satisfying to substitute the hydro system for our noisy oil -consuming diesel for even this short time. Disregarding the initial costs, we had the feeling of getting something for nothing. Ale we had power 24 hours a day rather than the 5 to 10 PM diesel operation which we had limited ourselves to. The extra round-the-clock power ca- pacity spurred us on to create additional applications. We added electz heaters in both the hatchery and house. In addition, we always had hot water, our emergency lighting batteries were always fully charged and we did not have to worry about overloading the diesel° < Refrigeration equip went could run as needed on a 24 hour basis rather than continuously during the 5 to 10 PM period. One of the most satisfying parts of the operation was the smooth perfora ance of the Woodward Governor. It compensated for any change in load with a definite motion and a minimum of hunting. We experienced some difficulty at first in utilizing all three phases of the 220 volts A.C. As new loads are created we distribute them to the best advantage to obtain a balanced load. This will be particularly tru when the cold storage plant is phased in. During the initial start-up period it would have helped if we had installed a 3-phase distribution panel in the house. This over -eight will be compensated for as new loads are added. As we gain experience and modify this equipment, we are hopeful that we can obtain year around operation. Even if we have to settle for a nine or ten month operation it will be well worth it. The heaviest load will be refrigeration and it is at the lowest during the cold winter months. We had similar difficulties obtaining year around water for our salmon hatchery the first two years. A dam was constructed to provide a deep pond for the water pick-up and this has solved that problem. VI PERFORMANCE The limitations to the designed operation now all hinge on improvements to the low dam at the water nick -UP. see Section IV AND VIII for other modifications made or planned. VII PROBLEMS A11 problems generated to date are discussed in Section IV an VIII. How- ever, they are also tabulated here to follow the outline provided. 1. Inadequate volume of water to operate at full load 2. Icing on metal filter -box screens. 3. Freezing of valves. 4. Freezing in filter -box filler pipes 5. Freezing in pipe at levels below jets (Bottom half of pipe) 60 Freezing in metal discharge pipes 7. Governor disengaged from pelton wheel after two months operation and generated a run -away situation which resulted in a burned -out bearing and scoured shaft. 8. Pipe movements in lowest sections. 9. Broken eye -bolt on pipeline tie. VIII MODIFICATIONS • � Our first modification was to change the point of water pick-up from an elevation above the power house of 150 feet to 200 feet. This permitted a more direct routing of the 10" PVC pipe, kept most of the pipe out of the scenic area near the creek, added 50 feet of head, simplified the point of pick-up and only required 400 feet more pipe. The change came a little late as the 25 KW alternator had already been ordered. However, we now have the option of going to 50 KW if our needs require by re- placing the alternator and modifying the belt drive and jets. Two of the four jets are now blocked off as they are not needed to generate 25 We The second modification was to construct a wooden filter box at the top of the system. A 10-inch filler pipe was run from the creek to the box. As might be expected, we found that when the pelton wheel was running with both jets open it sucked the water down the 10-inch pipeline faster than the 10-inch filler pipe could gravitate it into the filter box. The ad- dition of a second 10-inch filler pipe solved this problem. Freezing in the filler pipes, as water in the creek lowered, terminated all -operation on December 5, 19as. A temporary dam had been built in November on the sill of the waterfall by falling two trees across and sandbagging the voids. This served to keep a pond over the intakes fora while but was not efficient enough at lower creek.levels< Improvements this spring on the low dam should give a deeper pond behind the sill and improve chances for year around operation. We discovered in November that in freezing weather the metal screens in the filter box rapidly iced over and reduced the water flow. This situation woo awkuuvau uy ruwuvuipg une mezai screens ana substituting plastic scree The pipeline was installed to insure good gravity drainage with no pocket where dead water could freeze. An atmospheric vent was also installed at the top of the line. One oversight was at the bottom of the system where the jets are installed in the middle of the pipe. This permitted water t collect in the lower half of the pipe and obstruct operation of the main throttle valve. A drain plug will be installed at the low -point to insur complete drainage. We ordered a second set of reduced size jets to permit operating one jet on each runner at times of low water in the creek. It was originally planned to accomplish the same effect by shutting the water off on one runner by closing the 8" valve. However, we felt that this unbalanced operation might have contributed to the side pressure on the main shaft which separated the governor from the pelton wheel after two months operation. Improvement was made on the belt tightening method provided by the manu- facturer by adding a 1-inch rod with a left and right thread between the pelton and alternator. It was installed on the line of shaft centers to give a more direct push between units than by moving the alternator on the base plate alone. It also provides a very fine adjustment. The original discharge from the peltoa wheel consisted of an open concre# trough under the power house and then connected to three parallel 8-inch metal drain pipes running to the creek bed and discharging near MMM, r Rapid icing occurred in the metal pipes at below 100 so we plan to remove *._ them and allow the discharge to flow in an open ditch or wooden flume next winter. The filter box was designed to divert moat floating material, return it to the creek bed through the over flow and thereby reduce filter cleaning. A catch basin was also included to collect sediment. The box will be mode ified this summer to also permit deflecting all incoming water from the box and to also flush out sediment. This change was deemed necessary as operation of the valve at the top of the line was not dependable during Freezing weather. IX TIPS Do not underestimate costs and time delays to ship products to Alaska, particularly to a remote area, that does not have an established delivery service. Do not underestimate coat of electrical distribution components. Have a good electrician lay out the system and provide you with cost estimates. Make certain that the system can be shut down easily and that it will auto- matically drain itself. An atmospheric vent at the top of the system is a must, otherwise, a vacuum could be created during a blow-out that might collapse the pipe. Also, remember that valves do not operate when frozen. t Confine their locations to heated areas whenever possible. Limit large metal masses such as valves and metal screens in exposed areas a +hAv will hp fhp firaf fn frppfp. Keep bends in the pipeline to a minimum, particularly at the lower sections where pressure is the greatest. Anchor the pipeline well with adequate cross ties, particularly at large changes in direction. Include downrill ties to preclude the pipeline from crawling down the hill. X rj irMENT Peltech Pelton Wheel Manufactured by Small Two 14-inch Hydroelectric Systems and runners on c Equipment shaft with t ,5141 Wickersham jets on each Acme, Washington 98220 runner 25 KW Brushless Alternator Manufactured by Lima Three-phase (including ammeter) voltmeter, 200 E. Chapman Rd. 220 Volt A.C. cycle meter and phase Lima, Ohio 45802 selection switch) Governor Manufactured by Woodward Governor Company Fort Collins, Colorado PVC 10" pipe Distributed by Liberty Equipment Company 317 Iowa Bellinghami We* 98225 Fittings, Valves, Special Distributed by Material Benda Etc, Distributors, Inc... 13624 N.E. 177 Place Woodinville, Wa. 98072 Electrical meters, switches, Distributed by Stusser Elece distribution boxes, circuit 660 S. Andover Sto breakers etc. Seattle, Washington 98108 XI MONITORING PQode1 8558- i Simpson':` Twin -seal A watt -meter and. hour -meter are run continuously with the power system whet operating on the 12 KW Lister diesel or 25 KW hydroelectric plant. A volt meter skid pressure gage are installed in the residence to alert the owner of improper operation. A cycle meter, voltmeter, ammeter and pressure gage are installed in the power house to permit monitoring of all three phases of the 220 volt A.C. When the governor became disengaged from the Pelt ech 'it created a run-awa; situation. The light in the house increased in brilliancy and the sound from the power house changed. These changes were noted by the caretaker and the plant shut down. The Peltech manufacturer has suggested installing a vibration detector alarm to alert the operators of a mal-function. The system is visually inspected two or three times daily but an alarm would improve monitoring capability and possibly avoid problems before they be- f come serious. XII FINANCING tv owner *j0,j4b.UU By state grant 5,675.00 By federal grant _5 675.00 Total $49,696.00 XIII BUDGET See Final Technical Report on Hydroelectric System to D.O.E. XIV MISCELT..ANEOUS It is appropriate in closing to comment on our major unresolved problem which is the design of the Pelton Wheel. The separation of the governor from the runner shaft required a little research prior to serious commer A visit to the Skagway Power House of Alaska Power and Telephone Company disclosed that they have a similar type; i.e. two runners on one common shaft. It is a larger unit than ours but it has one basic difference, i has thrust bearings on each end of the shaft. Had ours been so equipped the chances of sideways shaft movement would have been eliminated. Now that we know what can happen, we know what to look for. The dogs that engaged the governor are visible from the outside. If there is a gradual separation that can be detected from a daily inspection, then we can live with the inherent weakness. But, if it occurs all at once, the we may have to modify the design by installation of thrust bearings or possibly positive stops. In the -future it will be routine maintenance t shut down periodically and check the bearing set screws located exterior to the casing. Furthermore, when the damaged shaft is replaced, it be- hooves us to flatten the shaft with a file where the set screws make con tact. If this doesn't do the job, the shaft could be drilled to accept the set screws. Installation of a second set screw could back-up the first and serve as a lock. Use of a glue -type lock -set is also adviseab In retrospect, it is unfortunate that no drawings, instructions or warra were provided by the manufacturer. Service has also been nominal. Submitted by <�d Eugeneards, Owner BILL SHEFFIELD, GOVERNOR L Pn DEFT. OF COMMUNITY & REGIONAL AFFAIRS Division of Community Development , October 14, 1983 Mr. Eugene W. Richards Box 455 Skagway, AK 99840 Dear Mr. Richards: SUBJECT: Department of Energy Grant # 657 OFFICE OF ENERGY PROGRAMS 3601 "C" STREET SUITE 722 ANCHORAGE, ALASKA 99503 (907) 561-4201 The State of Alaska in coordination with the U.S. Department of Energy (DOE) is planning to publish a book describing Appropriate Technology (A.T.) grant projects in Alaska. Your project has been selected to be included in this book. This project will be managed by the A.T. Program Manager in Alaska, Norman Bair. The available budget is very tight so we will be relying on input from the individual grantees like yourself. We have selected subtopics to be covered on each project as appropriate. These are listed on the enclosed page. They are taken from The Montana Renewable Energy Handbook. Written material needs to be received in our office by March 2, 1984 in order to keep our publishing schedule. It is voluntary, but I hope that you will be willing to provide the written material on your project with any sketches or graphics that may be helpful. We will provide editing of rough material from what you may provide. You may have already submitted your final reports on your project. If you think that the information is available in the reports, please let us know. In some cases we do not have copies, of reports submitted directly to DOE. If you have not written your reports, this project can also be used as your final performance report. 0 October 14, 1483 Page Two As you may be aware, the Alaska Division of Energy and Powe Development ceased existence on June 30th. The remaining energ programs are now handled in the Division of Community Developmen in the Department of Community and Regional Affairs. Our addres will continue to be that shown on the letterhead until December If you have any questions, you can contact Norman Bair at thi address or telephone 561-4201. We look forward to your participation in this project. Sincerely, S Ste ate , Chief Energy Conservation Section Enclosures