Page 5 - Electric News March April 2021
P. 5

to supply electricity, equipment issues like those at GGS could present more challenging situations.
DISTRICT NEWS 5
NPPD’s role in the Southwest Power Pool’s Integrated Energy Marketplace
What Caused the
Rolling Outages?
The limited rolling outages which occurred in February 2021 were an extraordinary and uncommon occurrence. An unprecedented convergence of events, including historically low temperatures across SPP’s entire footprint, low amount of wind generation, the lack of availability of natural gas and adverse impacts from the cold weather on certain fuels and generating equipment, resulted in more demand for power than supply. This combination of factors and its resulting consequences are so rare that since SPP’s inception 80 years ago, it had never before asked member utilities to shed firm load.
Why wasn’t Notice Provided in Advance of Rolling Outages?
When asked to curtail load by SPP, NPPD was required to respond immediately to stabilize the electric grid. Although rolling outages are inconvenient for everyone, the failure to react by NPPD or any other power provider could have caused sustained outages that may have lasted for days or weeks for large areas. The first priority is to immediately protect the transmission system to prevent more widespread outages from occurring. Due to the real- time generation to load balancing nature of the power grid, this means that predicting and communicating rolling outages is very difficult.
When directed by SPP to shed or reduce customer load, NPPD system control operators in Doniphan remotely opened breakers at NPPD 115 kV substations that resulted in outages for NPPD wholesale and retail customers, including Norris customers. NPPD quickly communicated when the breakers were opened but not before customers had already experienced an outage.
1
     Wholesale Energ2y Market
   3
  NPPD’s diverse generation resources are bid into SPP’s wholesale energy market, competing against other generators.
42 SPP selects the lowest-cost resources to run based on fuel
1
 Power Grid
 3
and variable operation and maintenance costs.
NPPD buys energy back from SPP to serve customers at market price.
 NPPD Wholesale Customers
4 NPPD delivers the electricity to wholesale and retail customers in Nebraska.
  NPPD Retail End- Use Consumers
Wholesale End-Use Consumers, Including Norris
  MARCH/APRIL 2021
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