Analysis Methodology for Balancing Authority Cooperation in High Penetration of Variable Generation

Abstract

With the rapidly growing penetration level of wind and solar generation, the challenges of managing variability and the uncertainty of intermittent renewable generation become more and more significant. The problem of power variability and uncertainty gets exacerbated when each balancing authority (BA) works locally and separately to balance its own subsystem. The virtual BA concept is based on various forms of collaboration between individual BAs to manage power variability and uncertainty. The virtual BA will have a wide area control capability in managing its operational balancing requirements in different time frames. This coordination results in the improvement of efficiency and reliability of power system operation while facilitating the high level integration of green, intermittent energy resources. Several strategies for virtual BA implementation, such as Area Control Error (ACE) diversity interchange (ADI), wind only BA, BA consolidation, dynamic scheduling, regulation and load following sharing, extreme event impact study are discussed in this report. The objective of such strategies is to allow individual BAs within a large power grid to help each other deal with power variability. Innovative methods have been developed to simulate the balancing operation of BAs. These methods evaluate the BA operation through a number of metrics-such as capacity, ramp rate, ramp duration, energy and cycling requirements-to evaluate the performance of different virtual BA strategies. The report describes a systematic framework for evaluating BA consolidation and coordination. Results for case studies show that significant economic and reliability benefits can be gained. The merits and limitation of each virtual BA strategy are investigated. The report provides guidelines for the power industry to evaluate the coordination or consolidation method. Several related projects are underway to work with regional BAs to evaluate the strategies defined in this report. v

Renewable Energy Integration in Zonal Markets

“…Constraint (16) enforces strong duality at the solution, i.e. it enforces equality of the total welfare with the total surplus (surplus minimization is the dual of welfare maximization).…”

“…In addition to day-ahead market design challenges, real-time operation posses several coordination challenges in systems with multiple operators [16]. Similar coordination mechanisms are used both in market coupling and wide US interconnections.…”

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