Welcome to WaRP, NHA’s new Waterpower Research Portal.

Installed wind generation capacity has increased at a rapid rate in recent years. Wind generation provides numerous economic, social and environmental benefits, but it also carries inherent variability and uncertainty, which can increase the need for additional balancing reserves, generation resources that can adjust their output rapidly to keep power supply in balance with demand. Hydropower is an inexpensive and flexible generating resource that has been considered one of the best resources to provide the necessary balancing reserves for wind. Hydropower’s flexibility and capacity are limited, however, by non-power constraints associated with environmental and water management objectives that have not been fully accounted for in previous wind integration studies. We present a methodology to evaluate hydropower and wind integration using the RiverWare river system and hydropower modeling tool. The model represents both the physical characteristics of the hydropower system and accounts for realistic non-power policy constraints. An economic evaluation is provided that includes the value of both energy and ancillary services. In addition, operational outputs include the ability to satisfy all policy constraints. The methodology is applied to a test case integrated hydropower and wind generation system including five hydropower projects in a run-of-river configuration for a range of wind penetration levels and hydrologic conditions. Results show that wind at low penetrations adds economic value to the system. As the installed capacity increases, additional wind generation has diminishing returns, primarily due to increased reserve requirements. Increased wind capacity also causes increases the number of policy constraint violations. Non-power constraints have a significant impact on total system value, but that relative impact varies depending on system conditions. Complex interactions between policy and the physical system result in a highly non-linear response of the system to changes in wind penetration. Utilization of goal programming makes it possible to capture these effects that would be missed without a realistic representation of both the integrated physical system and its operating policy. This methodology can be used to provide an improved representation of hydropower systems in future wind integration studies.

Hydropower is a fast responding energy source and thus a perfect complement to the intermittency of wind power. However, the eect wind energy has on conventional hydropower systems can be felt, especially if the system is subject to several other environmental and maintenance constraints. The goal of this paper is to develop a general method for optimizing hydropower operations of a realistic multireservoir hydropower system in a deregulated market setting when there is a stochastic wind input. The approach used is stochastic dynamic programming (SDP). Currently, studies on hydropower operations optimization with wind have involved linear programming or stochastic programming, which are based on linearity. SDP, by contrast, is a stochastic optimization method that does not require assumptions of linearity of the objective function. The true adaptive and stochastic nonlinear formulation of the objective function can be applied to multiple time steps, and is effcient for many time steps compared to stochastic programming. The preliminary results for the deterministic optimization demonstrates the potential of this method to guide operation of the hydro system knowing the state of the system. The research will continue with optimizing under uncertain inflows as well as wind.

Renewable energy, particularly wind power, has increased dramatically over the past two decades. In the Pacific Northwest, the power system has accommodated a large amount of new wind power. The variability of wind power has introduced many challenges, requiring additional reserve generation to be available to maintain system stability. The primary source for reserves is the Federal Columbia River Power System, and the aging dams of this system are believed to be near their limit for providing this service. This paper will explore the dynamics of the power system as a whole, and investigate the relationships that wind power has to the rest of the power system. Several types of studies have been used to examine these relationships including Maximal Information Coefficient analysis, Correlation analysis, and Regression analysis. The results of these analyses demonstrate that the dynamics of the power system changed as wind power was added to the system. The results will also show that the power system is increasingly reliant on resources other than hydropower, including thermal power and interties to California and Canada, to provide balancing reserves for wind power.

This project aims to explore the unique role of hydropower in producing significant amounts of firm renewable energy and storage to support VRE’s, and providing flexible energy services to support electricity systems – collectively termed ‘hydro balancing’. Specifically, Phase 2 will develop an understanding of two key strategic themes: (1) How hydropower may be valued in future electricity market scenarios, and (2) How hydropower may be valued in providing climate change adaptation services (e.g. flood control).Phase 2 will capture the contribution of hydropower by documenting the capabilities, challenges, opportunities, and market structures for compensating hydropower services in TCP member countries as well as additional countries recruited to the effort.