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Environmental Considerations. Finally, environmental impacts have a substantial bearing on the evaluation of any potential site. Factors such as recreation, fish and wildlife, and other public uses will have a decided effect on the acceptability...
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Embankment costs include the cost of earthfill dams and dikes, spillway or outlet works, and general reservoir costs, excluding intake structures. Cost methodology was tested by comparing result with those of recently built or planned pump-storage...
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Powerhouse cost data were derived from information made available by the Hydroelectric Design Branch of North Pacific Division. Cost information and curves for powerplants with reversible Francis pump-turbine units were developed from a computer...
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to depress the tailwater. For plants with moderately high heads (1,800 to 2,200 feet range), a separate Francis turbine can be used in place of the Pelton turbine. The Francis unit has the advantage of a somewhat higher speed than a similarly...
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Underground powerplants (similar to the one shown in this photo) could be used for most of the sites listed in this inventory. The photo is of Raccoon Mountain powerplant,
located near Chattanooga Tennessee, now under construction by Tennessee...
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Figures 12 and 13 show the waterway system for a typical surface-type powerhouse and a typical underground-type powerhouse. Many factors must be considered before final location and arrangement of the waterway system can be made. For uniformity,...
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PROCEDURE
Daily/Weekly Cycle Plants. From a map survey, suitable locations for the upper and lower reservoirs were selected, storage requirements calculated and penstock lengths determined. Project costs were then determined, based on individual...
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Image caption: Pumped-storage site on mainstem Columbia River, Mid-Columbia Subregion. Example of a site using Lake Umatilla (John Day Reservoir) as the lower pool: Indian Rapids (564) view looking south.
Image details POWER TUNNEL... |
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Image caption: FIGURE 13 Regional Map of Inventoried Pumped-Storage Sites - Weekly Cycle
Image details: POTENTIAL PUMPED-STORAGE SITES IN THE PACIFIC NORTHWEST DAILY/WEEKLY CYCLE |
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EVALUATION OF WEEKLY-CYCLE PLANTS
SUMMARY OF PHYSICAL DATA
Table 6 lists the potential weekly cycle pumped-storage sites in the region having an investment cost less than $240 per kw 2. Following the table is a brief explanation of the data...
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While it is not appropriate at this time to make a final judgment as to the desirability of individual projects, it is possible to point out some of the factors which might affect the feasibility of these projects, and to indicate which of these...
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COST ANALYSIS
Capacity Costs. The resulting pumped-storage project costs listed in Table 6 are strictly capacity costs. They do not include the cost of pumping energy and should not be directly compared with alternative peaking sources...
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Economic Feasibility. On the basis of the site cost data shown on Table 2 it appears that pumped-storage projects can be constructed having an annual cost of about $12.50 per kilowatt-year based on Federal financing at 6-1/8 percent. Pumping...
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TABLE 2
COMPARISON OF PUMPED-STORAGE ANNUAL COST WITH ALTERNATIVES
Annual Capacity Factor, Percent
FEDERAL FINANCING
25
20 15 10 7-1/2
5 2-1/2
1
0
Pumped-Storage $/KW-Year 1/
27.28 24.33 21.37 18.41 16.93 15.46 13.98 13.09...
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Figure 15 illustrates graphically how the total annual cost of pumped-storage within the capacity cost range of $9.00 to $16.00 per kw-yr compares with the thermal alternatives. It can be seen that pumped-storage generation would be about one-half...
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Image caption: FIGURE 16 Relative Costs of Peaking Power
Image details: RELATIVE COST OF PEAKING POWER (1975 COST LEVELS) $13.50/ kw CONVENTIONAL HYDRO $41.50 / kw COMBUSTION TURBINE $18.40 / kw PUMPED STORAGE ABOVE FIGURES... |
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DISCUSSION OF PHYSICAL EFFECTS
It is impossible to forecast all the physical effects that pumped-storage would have on this area. It is conceivable that certain reservoirs could be designated as recreation reservoirs and during the summer...
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Conversely, at the time of peaking operation, large quantities of water will be discharged into the pool from the adjacent pumped-storage reservoir simultaneously with the peak inflow from the next mainstem project upstream.
This type of...
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The selection of adjacent pumped-storage projects on the mainstem Columbia must be based on determining the combination of conventional and pumped-storage units which produces the greatest net benefit in keeping with the physical and environmental...
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system reserve operation. Other plants that were intended to operate at a variable daily load, now operate at a relatively constant daily output. Still other plants operate against special limits that were not foreseen in the original design....
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Seasonality of Peaking Requirements. The regional load pattern has a marked seasonal variation, as described on Figure 17. The winter months experience heavy loads while moderate to light loads occur in the summer months. Until hourly...
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1. The plant may be called on to operate at or near full capacity in the winter months of December and January, and to a lesser extent in November and February.
2. During the summer months, some plants may operate at reduced capacity because...
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EVALUATION OF RESULTS—SEASONAL PUMPED-STORAGE SUMMARY OF SITE INVENTORY.
A survey of the region was made to identify potential seasonal pumped-storage sites, using criteria and procedures discussed under INVENTORY OF SITES. Table 3 lists...
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In the course of the preliminary evaluation a number of assumptions were made which dictated the physical requirements of seasonal pumped-storage as well as their functional criteria. These were as follows:
1. Environmental impacts necessitated...
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4. Surplus energy will be available to recover the seasonal storage by pumping at little or no cost. Current Bonneville Power Administration secondary energy studies indicate that in the future, surplus off-peak secondary energy capability will...
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