15-10-2012, 12:25 PM
LOAD Shedding & Preventing the Next Blackout: policy…
LOAD Shedding.ppt (Size: 134 KB / Downloads: 55)
WHAT IS LOAD SHEDDING…?
Load shedding, normally used in industrial, large commercial, and utility operations, is monitoring electric usage continuously (usually by automated instrumentation) and shutting down certain pre-arranged electric loads or devices if a certain upper threshold of electric usage is approached. there are two reasons for doing it, both of them financially motivated.
power companies sometimes set up an industrial customer or a school with an electric billing rate in steps, i.e. if you are pulling less than this amount of electric current during certain times you get billed at one rate for the electricity you use but if you are pulling MORE than this amount of electric current during that time, you get billed at a higher rate, even if you use the same amount of electricity overall. the highest current you draw during the time period in question is your "peak demand".
Background
Shortly after 4 p.m. EDT on August 14, 2003
61,800 MW of electric load and more than 50 million people lost power in 8 states in the U.S. and in 2 Canadian provinces
This amounts to approximately 11% of the Eastern Interconnection
ELCON estimates that the direct cost of the blackout was between $4 and 10 billion
The blackout shut down:
At least 70 auto and parts plants and several major automobile-related office complexes
At least eight oil refineries
Roughly a dozen steel mills – including one where the loss of the ability to cool the furnace resulted in molten metal burning a hole in the side of the furnace – and the filing for Chapter 11
Over 30 chemical and petrochemical facilities
Inadequacies of FE’s System and ECAR’s Oversight
FE failed to:
Conduct rigorous long-term planning studies of its system
Conduct sufficient voltage analyses for its Ohio control area
ECAR did not conduct an independent review or analysis of FE’s voltage criteria and operating needs
Some of NERC’s planning and operational requirements and standards were sufficiently ambiguous that FE could interpret them to include practices that were inadequate for reliable system operations
Failure of RTOs to Provide Effective Diagnostic Support
MISO did not have certain real-time data so it was not aware of FE’s system problems
MISO’s RCs were using non-real-time data to support real-time “flowgate” monitoring
MISO lacked an effective means of identifying the location and significance of transmission line outages
PJM and MISO lacked joint procedures or guidelines on when and how to coordinate a contingency near their common boundaries.
NOTE: MISO:AS a fully integrated regional transmission organization, the non-profit Midwest ISO assures industry consumers of unbiased regional grid management and ...www.midwestiso.org