EECS4460.152.28.21.pptx
Power System Management
EECS 4460/5460-901
Lecture #15
Electricity Public Policy Issues
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Power Plant Operations
Safe and reliable day-to-day operations
Managing transients and outages
Fuel sourcing and waste disposal
Generation Dispatch
Reliable and economic dispatch of the units
Managing transients and outages
May include power marketing function
Transmission Operations
Safe and reliable day-to-day operations
Situational awareness
Managing transients and outages
Distribution Operations
Safe and reliable day-to-day operations
Handling routine construction and outage work
Storm recovery
Organizational Support
Operating the Power System
Area of highest visibility is “abnormal” operations
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Severe Weather
Fuel delivery issues
Environmental alerts
Forest or brush fires
Geomagnetic disturbances
Terrorist or sabotage threats
Actual attacks of physical or cyber assets
Transmission Operational Impacts which lead to “Conservative Operations”
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79% of the large utilities (>500k customers) have in-house meteorologists
Weather Forecasting has Become Critical
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ReCap: Storm Restoration is Highly Organized
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Historically coal and natural gas deliveries can affect plant availability
Coal: Regional, inventory stockpile, transportation
Natural gas: Regional, inventory via pipeline and storage
Coal and gas contract implications
The two-year nuclear fuel cycle results in fuel security
Recent regional pressures on natural gas availability
Typically, with “abnormal” weather
New England, Texas, California, Midwest
Generation reliability impacted
Fuel Delivery Issues
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New England Resorts to Oil Fired Generation (Winter 2017-18)
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Weather and Gas Supply Impacted Wholesale Power Prices in 2018…
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Cold weather “cyclones and vortexes”
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Winter 2020-21 natural gas storage withdrawals near record
Weekly net changes in natural gas storage
Heating degree days (HDD):
temperature-based measure of heating demand
U.S. Transmission System Map
Three major interconnections in the U.S.
Few Texas Interconnections
Preview of the NERC Interconnections
ERCOT (Electric Reliability Council of Texas)
Manages flow of electric power for more than 26 million customers – about 90% of the Texas load
History includes the 1930s when FDR signed the Federal Power Act
46,500 miles of transmission lines; 700+ generating units
Power generation is deregulated, and retail customers are required to select a supplier
A nonprofit company; governed by a Board of Directors and subject to oversight by the Public Utility Commission of Texas and the Texas Legislature. Commissioners are appointed by the Governor
Local utilities provide distribution services; most are investor owned
ERCOT Control Room Images
August 2019 in Texas
New Peak:
74,820 MW (8/12/19)
$9000/Mwhr
Demand response
@ 1750Mw
Rotating outages
@ 1000Mw
Planning Reserve 8.6%
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At one point, up to 46,000 MW of generation out of service
28,000 MW Thermal; 18,000 Wind and Solar
Frozen wind turbines, pipes and instrumentation; gas supplies
86,000 MW total capacity; peak demand 74,820MW (8/12/19)
Capacity: 51% Nat Gas, 25% Wind, 13% coal, 5% Nuclear, 4% solar
185 units tripped off-line Monday (of 710)
About 16,500 MW of customer load shed at highest point
Observations:
Equipment not well designed for temperatures this low
Texas not well interconnected with the rest of the country
ERCOT grid operators have recently run with very thin margins
Market design does not sufficiently support additional capacity resources
Wholesale price spikes passed on to customers
Investigations announced by FERC/NERC, Governor, etc.
Beginning Sunday Feb. 14, 2021 in ERCOT
Generation losses throughout the footprint
Texas natural gas production fell by almost half
Source: EIA February 25, 2021
Decline due mostly to “freeze-offs”: water and other liquids in the gas stream freeze at the wellhead or in the lines
February 7-18, 2021 in ERCOT
ERCOT Real Time LMP Market 2:30pm 2/17/21
A typical day in the ERCOT market (2/28/21)
Wind and Solar facilities are considered “non-dispatchable”
Solar peaks and load peaks are non-coincident
Inverters typically do not provide frequency control or load following
There have been curtailments however
Wind peaks are often in the early morning hours
Substantial work ongoing to resolve
Storage alternatives can mitigate the impact
Operating with Intermittent Resources
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Typical daily load and supply for California
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Integrating Solar Resources into the Grid
The “Duck Curve:
CAISO – California Independent System Operator
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“Three-Year Old Duck”
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August 14-17, 2020
August 16, 2020 New York Times
August 14 CAISO Net Demand
August 14 CAISO Supply
A more typical picture (Sept. 24, 2020)
And …smoke from the fires reduced solar generation
The CAISO Geography
Blue Cut Fire Event
August 2016 in Southern California
Major fire – 37,000 acres, 300+ structures
Transmission corridor: 3-500kv and 2-287kv lines
Fifteen line faults, voltage and frequency disturbance
1200MW of PV solar tripped offline
Inverter Interface with the Power System
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Inverter Interface with the Power System
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Inverter Interface with the Power System
Needs to be addressed as PV resources are added
Add “ride-through” and response attributes
Improve coordination with related protection schemes
NERC Task Force and Industry Standards efforts (IEEE1547)
Inverter manufacturers involved
Modeling techniques being refined
Industry alerts have been issued
Potential retrofit of dated hardware
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Environmental Alerts
Limitations on specific generating units – air and water
Can be regional, usually localized
Air quality, spills, discharges
Incident reporting and oversight
Forest and Brush Fire Impact is Growing
California utility actions
The “planned outage paradox”
Environmental Alerts and Forest/Brush Fires
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California Public Safety Power Shutoff
California’s major utilities participating
Criteria for localized shutoffs:
High wind and high wind gusts
Low Humidity
Dry vegetation
Fire threat
Real-time observations
National Weather Service “Red-Flag Warning”
California and neighboring states all have aggressive decarbonization goals
California: net-zero-carbon by 2045
Western half of U.S. has seen high loads (weather), mitigated somewhat by the pandemic
Regional gas supply issues, particularly California’s Aliso Canyon
Public power safety shutoff likely to continue
California retail residential electricity rates among the highest in the country
California is 20.45 cents/kwhr
Average U.S. is 13.20 cents/kwhr
Ohio is 11.80 cents/kwhr”
California Challenges
Electromagnetic Pulses (EMP)
A short burst of electromagnetic energy
Origin may be natural: lightning, meteor impact, solar corona burst
Or manmade: Power line surges, nuclear explosion, non-nuclear EMP weapons
High-altitude pulse is primary concern
Studies ongoing regarding impact and hardening
Geomagnetic Disturbances (GMD)
A form of electromagnetic pulse
Solar flares produce a “wind” of charged particles
Magnitude of the solar flare determines intensity of the GMD
GMD’s cause geomagnetically induced currents (GIC’s)
Geomagnetic Disturbances
Depiction of a corona
mass ejection (CME)
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The “Quebec Blackout Storm” - March 13,1989
Five 735 lines tripped; 9500MW generation lost
Quebec grid collapsed; 9 hours to restore
Salem(NJ) step-up transformer failed
Multiple lines tripped in northern U.S.
Ionizing particles from the sun interact with the earth’s magnetic field
Voltage potentials induced in the earths crust, resulting in geomagnetically induced currents traveling through the crust
Areas of igneous rock resist the flow – follows path of least resistance, up the ground path and along the lines and back to earth
Storm map reconstructed
from sensor data
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Reduce scheduled plant and line outages and/or maintenance
Purchase or make available more resources
Reduce transfer limits
Modify analysis, consider more conservative values
Staff backup facilities
Work with governmental agencies as needed
Increased communications/notifications
Conservative Grid Operations
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Ensure worker and public safety
Strong focus on workforce training and safety
Education of the public
Minimize environmental impact
Operate the system to minimize the impact on the environment
Plant emissions, construction work, spills and incidents
Minimize costs to the customer
Efficiency and productivity in all aspects
Monitoring and improving costs: operational and capital
Support community and customer needs
Supporting public works projects
Outage responsiveness, professionalism, customer interaction
Working within the industry
Event response and cooperation
Sharing best practices
Additional Operational Fundamentals
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Public Policy Continued
Industry events and regulation
Energy policy – federal and state
Merchant generation
Evolution of power markets
Changing business structures
Renewable policies
ISO’s, RTO’s and NERC
Next Lecture(s)
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