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Reference: ELT_296_8


The future of reliability - Definition of reliability in light of new developments in various devices and services which offer customers and system operators new levels of flexibility



The TB describes the findings of WG C1.27 that the definitions of reliability, adequacy and security must be revised in light of the developing two-way nature of the power system. Present worldwide conditions and expected trends show an increased use of customer generation and renewable generation technologies by individual customers, independent
developers, and utilities. In addition, there are potential new developments in communication and information processing that should accelerate these trends. All these trends point to increased customer participation as suppliers in utility markets and operation that often leads to power flowing out from customers’ facilities during many hours of the day.

This is a noteworthy change from the historical pattern of one-way flow of power from the utilities to their customers. This will likely require unbundling a range of services necessary for system operation that had been provided by a single utility in the past. The revised definitions for reliability recommended in the TB are likely just a first step in revising many of the aspects of planning and operating power systems. To ensure consistency with the proposed new definitions, utilities and system operators will need to revise existing criteria and standards and develop new criteria
and standards to incorporate the impacts of customer flexibility and the growing need for end-to-end approaches to markets, planning, operation and reliability. These revisions will impact markets, system planners, system operators, transmission owners, and distribution owners because of their differing practices and histories.


File Size: 2,3 MB

Pages NB: 3

Study Committee : C1 ?

WG (TF): WG C1.27

Year: 2018

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