EPA WEBINAR

JUNE 11, 2015

Gil Bindewald

Eric Rollison

Electricity 101
SECTION 1: 

OVERVIEW 

2
Electricity’s Role in Society

Electricity plays a vital role to our economy and national security. Most 

Americans can not describe what it is or where it comes from. Yet, we know 

the impact that electricity plays on nearly all aspects of our lives: national 

security; health and welfare; communications; finance; transportation; food 

and water supply; heating, cooling, and lighting; computers and electronics; 

commercial enterprise; and even entertainment and leisure.

3
Electric System Must Meet 

Evolving Expectations

Electrify transportation sector 

to reduce dependence on 

imported oil

Integration of diverse set of 

generation resources 

Maximize benefits of end-use 

efficiency and storage

Meet environmental constraints

Emerging Expectations

Affordable Power

Reliable Power

Secure Power

Historical Expectations

4
Challenge Ahead is Complex

• Over 3000 utilities with diverse

business models

– Investor-Owned Utilities 

– Electric Cooperatives 

– Public Power/Municipal Utilities

– Federal Government

• Limited demand growth

• Increased self generation (changing 

revenue stream)

• Diverse markets and regulatory 

frameworks

• Increased operational complexity

– Changing generation & load

– Cyber/physical concerns

– Weather events 

Source: North American Electric Reliability Corporation (NERC)

5
• Investor-Owned Utilities -- 192

– Account for a significant portion of net generation (38%), 

transmission (80%), and distribution (50%)

• Publicly-Owned Utilities and Cooperatives -- ~2,900

– Account for 15% of net generation, 12% of transmission, 

and nearly 50% of the nation's electric distribution lines

• Independent Power Producers -- ~2,800

– Account for 40% of net generation

• Federal Government

– Owns 9 power agencies (including 4 Power Marketing 

Administrations and TVA) with 7% of net generation 

and 8% of transmission

• Electric Power Marketers – 211

– Accounts for approximately 19% of sales to consumers

Sources: EIA, Electric Power Annual 2013, March 2015

 EIA, Annual Energy Review 2011, Chapter 8 (Electricity)

 2014-15 Annual Directory & Statistical Report, 

 American Public Power Association

 NRECA Co-op Facts & Figures, www.nreca.coop

Electric Industry

6
Electric Power Systems

Source: How Stuff Works

Four major components:

Load: Consumes electric power

Generation: Produces electric power

Transmission (and Distribution): Transmits electric 

power from generation to load

Control Centers: Coordinate generation and 

transmission assets for economy and reliability

Components are joined together 

at “buses” or substations.

Electric power systems involve the 

management of interconnected 

components needed to generate and 

deliver electric power to customers 

economically, reliably, and safely.

7
Load

• Load (from a utility 

perspective) typically 

begins at the meter.

• The meter measures a 

customer’s energy use.

8
Source: TVA (2007)

Generation

9
Substation

Source: OSHA

• Changes voltage from one level to 

another

• Connects electric generating plants 

to the system

• Makes interconnections between the 

electric systems of more than one 

utility

• Switches transmission and 

distribution circuits into and out of 

the grid system

• Regulates voltage to compensate for 

system voltage changes

• Measures electric power qualities 

flowing in the circuit, and connect 

communication signals

10
Size and scale

Operation is fundamentally different

– Transmission system: operated actively

– Distribution system: operated passively

Failures lead to different consequences

– Transmission system: widespread 

blackout or large block load shed

– Distributed system: impacted power 

quality, local area

Transmission/Subtransmission Voltage Levels

69kV up to 765kV AC; 800kV HVDC

Distribution Voltage Levels

Medium Voltage

4.16 kV – 46kV

Low Voltage

480 V

120/240 V (single-phase)

Major Differences between 

Transmission and Distribution Systems

11
SECTION 2:

SYSTEM OPERATIONS

12
Key Section Objectives

• Illustrate how load and generation change over 

time

• Characterize who is involved in the operation 

of the electric system

• Describe how the electric system is operated 

today, and the complexity of the task

• Identify some of the emerging operational 

challenges

13
Load is not constant

1

2

3

4

5

6

Maximum kW usage

12 2 4 6 8 10 12 2 4 6 8 10 12

Noon

A.M. P.M.

Midnight Midnight

Average Demand

1.8 kW

Peak Demand

6.5 kW for 15 minutes

Sleeping

Breakfast Preparation

Morning Activities

Lunchtime

Dinner Preparation

Afternoon Activities

Dinnertime

Evening Activities

Hypothetical Power Usage

for an American Household

Typical office building Typical hotel Typical theater

AM PM AM PM AM PM

14
Aggregate Load

PJM Winter Load

(Hypothetical Example)

Peak: 37,000 MW

Valley: 26,000 MW

LF Range: 11,000 MW

Max ramp rate between 

5 and 6 AM:

3450 MW/hr or 

57.5 MW/min

31,450

TYPICAL WINTER LOAD

TYPICAL SUMMER LOAD

15
Markets / Regulatory Structure

• U.S. has a blend of structured pool-based markets and 

traditional vertically integrated regulated areas

• State regulators are accountable for distribution and 

intrastate transmission rates

• FERC is responsible for interstate transmission

Source: ferc.gov

North American Regional Transmission Organizations

Regional Transmission 

Organizations (RTOs): 

Independent entities, 

established by FERC Order 

2000 issued in December 

1999, that control and 

operate regional electric 

transmission grids free of any 

discriminatory practices. 

16
• Bilateral contract – a buyer and seller negotiate directly and sign a 

two-party contract to trade electric power. 

• Outside the RTOs/ISOs—mainly the Southeast and the West outside 

of California—wholesale power trades occur through bilateral 

contracts. 

• Within the RTOs/ISOs, there are both bilateral trading and 

“organized” markets that pool all sellers and buyers. 

Bilateral vs. Organized Markets

Definitions:

RTO = Regional Transmission Organization

ISO = Independent System Operator 17
Economic Dispatch

Source: e-education.psu.edu

Building the Economic Dispatch

Economic Dispatch means 

“the operation of generation 

facilities to produce energy at 

the lowest cost to reliably 

serve consumers, recognizing 

any operational limits of 

generation and transmission 

facilities” 

-- Energy Policy Act 2005, Sec. 1234 (b)

18
Economic Dispatch Limits

Factors that affect and dictate grid constraints:

– Generation and transmission facility conditions and availability 

• Examples: whether a unit or line is out of service for maintenance or must operate 

under reduced limits

– Line capacities under different power flows and loading

• Thermal limitations – transmission and distribution wires have limited capacity; 

heat can cause damage and excess sag.

• Angular Stability – disturbances on the system (switching, contingencies, etc) may 

cause the system to become unstable and lose synchronism 

• Voltage Stability – high demand/loading on transmission can, with insufficient 

reactive power compensation, cause voltages to become unstable and difficult to 

control 

– The availability and capabilities of other grid facilities to buffer and 

manage line loadings and voltages

• Examples: circuit breakers, series or shunt reactive devices, transformers, and 

other equipment and protection schemes

19
System Operations

• Assuring system reliability per NERC 

standards at different system levels 

– Local

– Balancing area

– Interconnection

• Scheduling, dispatch, and control

• Transmission congestion management

• Measurements to monitor the system

– State estimation

– Contingency analysis

– Load and generation forecasting

• Additional responsibilities

– Ancillary services (and markets)

– Security coordination 

– Emergency response and coordination

Source: TVA

20
Ancillary Services

Normal Conditions

• Regulating reserves

• Load following reserves

Event Conditions

• Contingency

• Ramping

Other Services

• Voltage Control

• Black Start

Acknowledgement: PNNL

Ancillary Services: services additional to provision of energy 

to support power system reliability

21
Operational Challenges

• The future generation resource mix is unknown

• The variability and uncertainty of renewable energy sources (e.g., wind and 

solar power) require new ways to operate the power system (including the use 

of storage, natural gas, demand response, inter-hour scheduling; market 

impacts)

• Load profiles are uncertain as on-site renewable energy resources, demand 

response technologies, and EVs/PEVs are introduced to distribution systems

• Valuation of ancillary services is evolving 

• Boundary seams are critical for effective integration

• New concerns are continually emerging 

Definitions:

EV = electric vehicle

PEV = plug-in electric vehicle 22
Variable Energy Resources 

Sources: EIA from Bonneville Power Administration data, California ISO [W. Booth, EIA]; Renewables Watch (CAISO)

Actual Demand and Wind Output for the Bonneville Power 

Administration, June 22-23, 2013

Actual Output of Renewable Generators in 

the California ISO, March 2, 2014

23
Availability of Smart Grid 

Data Enhances Flexibility

“Smart Grid” data sources enable real-time precision in operations and 

control to dynamically optimize grid operations to adapt to changing 

conditions

– Real-time data from distribution automation and smart meter systems will 

significantly advance real-time operations of distribution systems and enable 

customer engagement through demand response, efficiency etc. 

– Time-synchronized phasor data, linked with advanced computation and 

visualization, enable advances in state estimation, real-time contingency analysis, 

and real-time monitoring of dynamic (oscillatory) behaviors in the system.

Customer Systems Customer Systems Customer Systems Customer Systems

Customer Systems Advance Metering 

Infrastructure

Electric

Distribution 

Systems

Electric 

Transmission 

Systems

24
Energy Storage

Energy storage would allow us to change the way we operate 

electricity systems 

• Responds 

instantaneously for 

peak shaving and 

bridge outages

• And makes renewables 

dispatchable

Energy storage provides 

energy when it is needed just 

as transmission provides 

energy where it is needed

Source: DOE, Dr. Imre Gyuk; Sandia National Laboratories

25
Section Recap

• Operating Characteristics of Electricity

– Demand varies considerably over the year, week and day. 

– Electricity storage is limited and expensive.

– Electricity is produced the moment it is consumed.

– Utilities rely on reserve capacity for unexpected loss of supply. 

• Utilities dispatch resources to follow demand based primarily on 

lowest cost to consumers, while recognizing system limits.

– Electricity market structures reflect regional diversity

– There is a difference between cost and price of electricity.

– Cost to generate electricity varies minute-to-minute.

• Opportunities for innovation and transformation exist to address 

emerging challenges

26
SECTION 3: 

SYSTEM PLANNING 

27
Key Section Objectives

• Who develops system plans 

• What is included in system plans

• When are system plans developed

• How are system plans are developed

• What are current system planning practices

28
Who Develops System Plans

• Within the Bulk Power System, the Planning 

Authority coordinates and integrates within its 

boundaries: 

– Transmission facility and service plans,

– Resource plans, and 

– Protection system plans

• A Planning Authority Area is not constrained 

• As of May 2015, there are approximately 74 entities 

which perform the Planning Authority function 

within the US

29
Key Elements of the 

Electric Power System Plans

Source: How Stuff Works

Three Major Components

Transmission facility and service plans

Whether elements are in or out of 

service and what the facilities future 

schedules are planned 

Resource Plans

Future plans for generation and 

resources and their availability to 

deliver power to the grid 

Protection System Plans 

How protection system elements are 

configured on the system and what are 

their activation points

30
What is included in 

Future System Plans

The Vogtle Unit 3 cooling tower | U.S. Department of Energy, 

Photo courtesy of Georgia Power Company.

 New Generation Resources

 New Transmission 

Infrastructure

• Substations

• Transmission Lines

 Upgraded Generation Units 

 Upgraded Transmission 

Infrastructure

 Forecasts of generation 

retirements 

 Technical System 

Requirements

• Thermal requirements

• Voltage Requirements 

Southern Company – Kemper County | U.S. Department of 

Energy

31
When are System 

Plans Developed

System Plans are developed on a defined 

cycle, typically occurring on an annual basis. 

• The system plan development cycle is based 

upon a number of external factors and regional 

needs

• Check with your local Planning Authority to 

understand their cycle

32
How are System Plans 

Developed

Planning 

Authority 

identifies 

system 

attributes and 

scenarios for 

study Stakeholders 

review system 

attributes and 

scenarios and 

provide 

comments

Planning 

Authority 

simulates 

future 

scenarios

Planning 

Authority 

identifies 

necessary 

system 

reinforcements 

for reliability

Planning 

Authority files 

plan with 

appropriate 

regulatory 

authorities

Stakeholders 

review and 

comment on 

filed plan

Regulatory 

authorities 

approve final 

plan 

Each planning cycle 

starts with the 

development of a 

new plan and is 

continuous.

33
• Forecasting the availability of 

resources

– Traditional resources

– Renewables

– Hybrid and New Tech

• Forecasting future loads

– Economic Growth

– Population growth 

– Other attributes 

• Incorporating policy mandates

– Loss of Load Expectation

– Reserve Margin

– Renewables and other mandates

What are Current System 

Planning Approaches

34
Section Recap

• Who develops system plans

– System plans on the bulk system are overseen by the NERC 

Registered Planning Coordinator 

• What is included in system plans

– System plans typically include forecasts of future electricity demand 

and future resource availability. Plans attempt to manage 

uncertainty 

• When are system plans developed

– System plans are typically formulated on a yearly basis by Planning 

Coordinators

• How are system plans are developed

– System plans are typically developed through an open, technical 

process

• What are current system planning practices

– Practices include resource forecasts, load forecast scenarios, and 

loss of load (contingencies) scenarios

35
SECTION 4: 

RESOURCES FOR MORE INFORMATION

36
Federal Agencies

Federal Agencies involved in Electricity Systems Analysis

□ U.S. Department of Energy

□ Federal Energy Regulatory Commission

□ Nuclear Regulatory Commission

□ Energy Information Administration

□ Environmental Protection Agency

□ U.S. Department of Interior

□ U.S. Department of Defense

□ U.S. Army Corps of Engineers 

□ U.S. Department of Agriculture

□ U.S. State Department

37
Data Collections

Helpful Data Resources

– Form EIA-411 Coordinated Bulk Power Supply and Demand 

Program Report

– Form EIA-860 Annual Electric Generator Report

– Form EIA-861 Annual Electric Power Industry Report 

– Form FERC-714 Annual Electric Balancing Authority Area and 

Planning Area Report

– Form OE-417 Electric Emergency Incident and Disturbance 

Report

38
Additional Federal Resources

U.S. Department of Energy 

– Quadrennial Energy Review

– National Electric Transmission Congestion Study

Federal Energy Regulatory Commission 

– Energy Infrastructure Update (Monthly)

– Market and Reliability Assessment (Semi-Annual)

Energy Information Administration

– Short-Term Energy Outlook 

– Annual Energy Outlook

– Electric Power Monthly 

39
Thank you

Presenters:

Gil Bindewald

Office of Electricity Delivery and Energy Reliability

U.S. Department of Energy 

gilbert.bindewald@hq.doe.gov

Eric Rollison

Office of Electricity Delivery and Energy Reliability

U.S. Department of Energy 

eric.rollison@hq.doe.gov

Electricity Policy Technical Assistance Program:

Caitlin Callaghan

Office of Electricity Delivery and Energy Reliability

U.S. Department of Energy 

caitlin.callaghan@hq.doe.gov

40