June 1 , 2002
The Near-Term Fix
and much more immediate than huge investment in new power lines. The more urgent message is: Start now, because it won't be long until we face this problem again. How many days until next summer's heat wave? Or the first ice storm?
According to a recent Edison Electric Institute reliability report, 67 percent of outages are weather-related. (The majority of other known causes involve human or animal interference with lines, planned or otherwise.) It is the single greatest factor affecting load and supply, but it can be much more closely monitored. Currently this isn't happening; many transmission operations do not have access to the most sophisticated weather information available, nor do they have analytical tools to process the granular data.
How can risks be better managed from within? If operators could access and analyze detailed surface weather observations, they would be able to more reliably and efficiently operate assets. Operators could, with greater certainty, anticipate areas vulnerable to heat, lightning, or ice. Dynamic line rating systems and granular weather data lead to more accurate monitoring of specific transmission lines' capacity utilization. With improved load forecasts, operators would know more quickly and with greater certainty when weather was causing load deviations from schedule. During potential storm events, repair crews could be dispatched in advance with greater certainty, thus reducing outage duration and unrecoverable revenue loss. And, as interregional transmission of power continues to grow and to further strain existing infrastructure, operator access to weather conditions beyond the control area will become even more critical to successfully balancing power on the grid.
Implement Risk-Avoidance Technology And Processes
This weather example illustrates a recursive process that transmission organizations should be incorporating now into daily operations to reduce legal, regulatory, and economic risks. Intended as short-term risk mitigation, this process (see Figure 1) is designed to help transmission operators look just days ahead.
Now add more robust data and enhanced analytical tools to this four-step risk-mitigation process, and operations are unquestionably better prepared to anticipate inevitable transmission strains and take pre-emptive action (see Figure 2).
The steps are described in detail below, in terms of their data and technology underpinnings.
Better Monitoring: Watching What's Really Happening
As described in the weather example above, transmission operators require access to more accurate, illustrative data to gain a better picture of weather. The same goes for load, capacity, generation, and transmission data. Generation and transmission data from outside an operator's control area can provide access to changes in other companies' operations that may eventually impose risk to his or her own company.
Sean O'Leary, CEO of Genscape Inc., pointed out, "On Aug. 14, data from our sensors began showing imbalances forming as transmission lines failed. Generation went offline over two hours before the fatal cascading outage-it was a major indicator that something was wrong."
Atlanta-based Genscape provides data from more than 1,200 sensors that monitor key generation and transmission assets in real time. Access to, and analysis of, data like Genscape's might have allowed companies to isolate the problem before it affected such a large area.
Enhanced weather, generation,