2 - Incremental dynamic programming in optimal reservoir operation

Summary

Very often reservoirs are built and operated to satisfy water quantity requirements such as irrigation or drinking water consumption, hydropower production, etc. Operation of these reservoirs is vital to maximize benefits and DP in various forms can be applied for this purpose. This chapter illustrates the applicability of several different forms of incremental dynamic programming (IDP) in the derivation of optimal operation patterns for different reservoir systems.

IDP IN OPTIMAL RESERVOIR OPERATION: SINGLE RESERVOIR

Dynamic programming can be applied to derive optimal operation policies for a single reservoir. Use of conventional DP in this task is one possibility. This section shows the application of IDP for two reservoir systems: (a) the Kariba Reservoir in Zambia and Zimbabwe, and (b) the Ubol Ratana Reservoir in Thailand, based on the analysis of Budhakooncharoen (1986, 1990). The IDP technique, which considers only a limited state space at a time, has lower computer storage requirements.

Application of IDP to the Kariba Reservoir

The Kariba Reservoir is a single-unit water resource system that utilizes the water resource of the Zambezi River to produce hydroelectric energy. The Zambezi River rises in northern Zambia. After flowing through Angola, it forms the boundary between Zambia and Zimbabwe. Finally, it passes through Mozambique to discharge into the Indian Ocean north of Beira. Figure 2.1 shows the Zambezi River basin. The catchment area of the basin up to the Kariba Dam is about 665 600 km². The Kariba Reservoir is shared and operated by CAPCO (Central African Power Corporation).