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Show Reservoirs in parallel example - MILLCREEK and AVON Figure 5.3 illustrates the relative configuration of the 2 reservoirs and the demand areas, a single M& I and a single Irrigation demand area is supplied from both the reservoirs. Hydropower generation is considered at both reservoirs. The Blacksmith Fork data and the S. Fork Lower Bear River data were used. Table 5.6 presents the results for this application. The optimal objective value for these reservoirs is $ 0,901 million. The total storage for Millcreek is at its upper bound of 70,086 Acre- feet, while that for Avon is at 12,833 Acre- feet. The reservoirs are full at the end of the simulation period as evident from the feasibility of constraints FAS01 and FAS02. The ratio of dead storage to total storage is at its lower limit of 0.2 in each case. The total M& I and irrigation demand constraints are satisfied, at essentially their lower limits. Values of the decision variables are then presented. The M& I and Irrigation yields from Avon MI0201 and IR0201 are at their lower bounds, while those from Millcreek are within bounds, such that the total demands are met. No firm release for Hydropower is provided at either reservoir. Millcreek has a hydropower generator of 1.217 MW, while no generator is selected for Avon. In fact, the magnitude of the dual activity with respect to G02, the generator size variable for Avon, indicates a strong lack of preference for accommodating a generator. The solutions indicate a preference for reducing the lower bounds of the dead storage ratio constraints, through the DUAL ACTIVITY levels. A preference for a reduction in the level of the irrigation demand is similarly indicated. Table 5.7 presents the statistics generated for this application. The general nature of the results is similar to those for the previous application. It is seen that Avon has relatively small net benefits. It is also seen that the magnitude of the recreation benefits is large enough to perhaps strongly influence the feasibility of these reservoirs. The optimum levels of these two reservoirs imply an overall benefit- cost ratio ( BCR) of 1.67 for Millcreek and 1.19 for Avon, which compare with 1.74 for Oneida and 9.46 for Amalga in the previous application. Overall the Millcreek- Avon combination has a BCR of 1.54 compared with a BCR of 5.21 for Oneida- Amalga. In both applications, one reservoir was developed to its limit and the other to a value within the bounds. RESERVOIR SYSTEM EXAMPLE: 7 BEAR RIVER SITES Figure 5.1 illustrates the configuration of the 7 reservoirs, the 4 M& I demand areas, the 3 irrigation demand areas and the Bird refuge ( treated as irrigation area number 4, with a benefit of $ 40/ Acre- ft.). All parameters used are similar to those used before. Return flows passing into various reservoirs are as depicted. The notation is that if the M& I or irrigation demands are taken from the stream below a reservoir, these releases may be passed through the hydropower plant. When these releases are shown coming out of the reservoir triangle, they may not be passed through the hydropower plant. Reservoir 5 - Washakie has a diversion from the Bear River above Honeyville as its only inflow. Accordingly, DxxOS variables were set up to recognize that flows released from the upstream reservoirs 2 ( Amalga), 3 ( Millcreek) and 4 ( Avon), may be diverted to Washakie. Reservoir 7 - East Promontory, is used only to supply the Bird Refuge. Its inflows comprise the releases from Honeyville ( 6) and Washakie ( 5), intermediate reach gains and the Malad River. The system represented by these 7 reservoirs and the 8 demand areas is thus more complex than the previous examples. Table 5.8 presents the output. The optimal net annual benefits for the system are $ 33.208 million, and storage is provided at all of the six reservoirs considered. As was 132 |
