Finding 6.11 As advanced storage technologies become available, strategies should be explored to use them to increase the performance and the resiliency of power systems.

Findings on the Distribution System

Finding 6.12 Being able to reduce load, and to focus on serving critical customers, can make the power delivery system far more robust in the face of natural disruption or terrorist attack. In many distribution systems, it is currently difficult or impossible to serve only a subset of customers on a distribution feeder. However, the technology is readily available to facilitate such selective service through distribution automation and intelligent load shedding.

Finding 6.13 Distribution systems operating at close to their design limits or systems operating with degraded equipment fail more easily and make restoration of service more difficult. State regulators should require distribution companies to assess the status of their systems and, where appropriate, require the installation of systems that monitor and diagnose the health and robustness of distribution, and support condition-based maintenance and repair. Systems that are operating with adequate capacity margins, and with all apparatus in good condition, are clearly more robust in the face of attacks or outages.

Finding 6.14 Greater use of automated distribution and load-shedding management holds the potential to reduce the vulnerability of the existing power system. Increased deployment of distributed generation and planning for the use of these facilities in the event of contingencies could greatly reduce the impact of an extended outage. Most of the needed technology for these concepts already exists.

Recommendations

Recommendation 6.1 The electric reliability organization (ERO) should require power companies to reexamine their critical substations to identify serious vulnerabilities to terrorist attack. Where such vulnerabilities are discovered, physical and cyber protection should be applied. In addition, the design of these substations should be modified with the goal of making them more flexible to allow for efficient reconfiguration in the event of a malicious attack on the power system. The bus configurations in these substations could have a significant impact on maintaining reliability in the event of a malicious attack on the power system. Bus layout or configuration could be a significant factor if a transformer, circuit breaker, instrument transformer, or bus work is blown up, possibly damaging nearby equipment.

Recommendation 6.2 The ERO and FERC should direct greater attention to vulnerability to multiple outages (e.g., N-2) planned by an intelligent adversary. In cases where major, long-term outages are possible, reinforcements should be considered as long as costs are commensurate with the reduction of vulnerability and other possible benefits.

Recommendation 6.3 The ERO and FERC should develop best practices and standards in improving system-wide instrumentation and the ability of near-real-time state estimation and security assessments, since otherwise operators are at a disadvantage trying to understand and manage system disruptions as they unfold. System operators should be able to observe what is going on well beyond their own borders whenever necessary. Reliability coordinators can oversee larger areas, maybe comprising several balancing authorities, but new entities should be established to oversee the whole Western and Eastern interconnection.

Recommendation 6.4 Local load-serving entities should work with local private and public sector groups to identify critical customers and plan a series of technical and organizational arrangements that can facilitate restricted service to critical customers during times of system stress. DHS could accelerate this process by initiating and partially funding a few local and regional demonstrations that could provide examples of best practice for other regions across the country.

BIBLIOGRAPHY

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