Published on EGEE 401: Energy in a Changing World (https://www.e-education.psu.edu/egee401)

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Unit 3, Lesson 5

Introduction

Unit 3: International Electricity: Generation, Use, and Demand – Lesson 5: Electricity Demand and Management

About Unit 3 and Lesson 5

Unit 3 covers three lessons: Electricity Demand and Management, Non-Renewable Energy Sources, and Renewable Energy Sources.

Lesson 5 focuses on the global demand for electricity and the infrastructure for its distribution—how much we and others use (demand), how it is distributed from the point where it is generated to the point where it is used, and how the supply and demand for electricity is managed.

What will we learn in Lesson 5?

With the successful completion of this lesson, you will be able to:

  • quantify electricity demand domestically and internationally;
  • draw a diagram showing how electricity is transmitted and distributed from the point of generation to the point of use;
  • describe how the power grid works now and may work in the future (the "smart grid").

What is due for Lesson 5?

The table below provides an overview of the requirements for Lesson 5. For details regarding the assignment, refer to the page(s) noted in the table.

Please refer to the Calendar in ANGEL for specific time frames and due dates.

Lesson 5 Requirements
REQUIREMENT LOCATION SUBMITTED FOR GRADING?

Reading: (International Electricity Demand): "World Energy Outlook," from International Energy Agency (as designated)

Page 2

No

Reading: (Domestic Electricity Demand): "Annual Energy Outlook," from U.S. Energy Information Administration (as designated)

Page 3

No

Reading: (Domestic Electricity Demand): EIA Tables of Electricity Generation (designated sections) and U.S. Census Bureau data

Page 3 No
Viewing: (Power Grid): "How the Grid Works" from Burn, Public Radio Page 4 No
Reading: (Power Grid): From Energy Explained, "How Electricity is Delivered to Consumers" Page 4 No
Simulation: (Power Grid): "The Power Grid" from MSTE Page 4 No
Reading: (Grid Management): From TVA, "Raccoon Mountain" (designated sections) Page 5 No
Viewing: (Smart Grid): "Smart Grid" from PBS Nova Page 6 No
Reading: (Smart Grid): SmartGrid.gov Page 6 No
Lesson 5 Activity: Complete Lesson 5 Activity. (It's in Canvas, in the Unit 3 Module) Page 7 Yes
Unit 3 Discussion Forum: "Smart Grid" (It's in Canvas, in the Unit 3 Module) Page 8 Yes

Questions about EGEE 401?

If you have any questions, please post them to our Questions about EGEE 401? Discussion in CANVAS. Use this Discussion for general questions about course content and administration. I will check it daily to respond. While you are there, feel free to post your own responses if you, too, are able to help out a classmate or have a related question.

 

International Electricity Demand

World Energy Outlook 2016 cover photo
World Energy Outlook 2016
Credit: International Energy Agency

World Energy Outlook [1](WEO) is an annual publication from the International Energy Agency [2] (IEA) that provides "energy market analysis and projections, providing critical analytical insights into trends in energy demand and supply and what they mean for energy security, environmental protection and economic development." (World Energy Outlook: About [3])

WEO 2016 provides analysis and projections through the year 2040. How does the IEA do this?

Since 1993, the IEA has used a simulation model called the World Energy Model (WEM) to generate the projections that are used in the annual WEO. The model replicates worldwide energy markets and has three main sections: final energy consumption (including residential, services, agriculture, industry, transport and non-energy use), energy transformation (including power generation and heat, refinery and other transformation), and fossil-fuel and bioenergy supply.

The primary outputs of the model are energy flows by fuel, investment needs and costs, CO2 emissions and end-user pricing--all, by region. (For more detail see the section Methodological approach, in the assigned reading.)

Of course, even the IEA with its huge models doesn't know exactly what the future holds. The future? We all know, well...it depends! To address "it depends" the IEA establishes sets of assumptions called scenarios. (This is standard practice in all future-based modeling.) In WEO16, the IEA has established three scenarios, differentiated primarily by their underlying assumptions about government policies:

  • Current Policies Scenario (CPS) based on government policies that were formally adopted by mid-2016, together with relevant policy proposals.
  • New Policies Scenario (NPS) takes into account the policies affecting energy markets that had been adopted as of mid-2016, together with relevant policy proposals. This is the WEO's "central" scenario.
  • 450 Scenario (450S) assumes a set of policies that will have a 50% chance of limiting the global increase in average temperature in 2100 to 2°C above pre-industrial levels. This would require limiting the concentration of greenhouse gasses in the atmosphere to around 450 parts per million of CO2 equivalent (ppm CO2-eq)

Section 1.1 of WEO16 describes the scenarios in greater detail.

Reading Assignment

The full WEO16 is available to you through Penn State Libraries (woo hoo!)

  • Go to PSU Library [4] and under Research, select Databases by Title (A-Z).
  • Search for OECD iLibrary and open it.
  • Enter the search terms energy outlook. Select and download World Energy Outlook 2016.
  • In Executive Summary
    • Read intro and The world’s energy needs continue to grow, but many millions are left behind, pages 21-22
    • Read The policy focus shifts to integration, pages 24-25
    • Read Energy and water: one doesn’t flow without the other, page 28
  • In Power sector outlook
    • Read Highlights, page 241
    • Read section 6.1 Recent policy and market developments, pages 242-244

Note:

OECD stands for Organisation of Economic Co-Operation and Development. For a current list of member countries, and more interesting info, please see OECD Members and Partners [5].

 

Domestic Electricity Demand

To understand current and projected domestic electricity demand, we'll use data from the U.S. Energy Information Administration (EIA), the statistical and analytical agency within the U.S. Department of Energy.

The U.S. Energy Information Administration (EIA) is the statistical and analytical agency within the U.S. Department of Energy. EIA collects, analyzes, and disseminates independent and impartial energy information to promote sound policymaking, efficient markets, and public understanding of energy and its interaction with the economy and the environment. EIA is the nation's premier source of energy information and, by law, its data, analyses, and forecasts are independent of approval by any other officer or employee of the U.S. government.

EIA conducts a comprehensive data collection program that covers the full spectrum of energy sources, end uses, and energy flows. EIA also prepares informative energy analyses, monthly short-term forecasts of energy market trends, and long-term U.S. and international energy outlooks. EIA disseminates its data, analyses, and other products primarily through its website, EIA.gov.

The Department of Energy Organization Act of 1977 established EIA as the primary federal government authority on energy statistics and analysis, building upon systems and organizations first established in 1974 following the oil market disruption of 1973. Located in Washington, DC, EIA is an organization of about 370 federal employees, with an annual budget in Fiscal Year 2016 of $122 million.

Source: Energy Information Administration Mission and Overview [6]

Each year, the EIA publishes its Annual Energy Outlook. This publication provides longterm projections of energy supply, demand, and prices, based on results from EIA's National Energy Modeling System [7] (NEMS). The EIA's future projections are based on sets of assumptions called cases (same as "scenarios").

Annual Energy Outlook 2017 (AEO2017) considers a Reference case (assumes current trends, laws and regulations) and five side cases: Low and High Oil Price, Low and High Economic Growth, and High Oil and Gas Resource and Technology. (For more info, see Introduction [8]). The EIA explains, "Projections by EIA are not statements of what will happen but rather modeled projections of what may happen given certain assumptions and methodologies." (page 4)

Now, we'll drill down into domestic electricity generation and demand. The steps below direct you to a specific document on the EIA site, but along the way you'll see links to all kinds of related information and resources. If you have a few minutes to spare, take time to poke around!

Research Energy Data

Visit the U.S. Energy Information Administration [9] website

  • Under "Outlooks," select and download "Annual Energy Outlook 2017" (release date January 5, 2017)
  • In "Overview/key takeaways", read (closely scan, pages 7-10 and 19-20.
  • In "Electricity Generation," read (closely scan, pages 69-70 and 75-76.

Return to U.S. Energy Information Administration [9]

  • Under "Sources & Uses," select "Electricity."
  • Near the top of the page, hover over the tab "Analysis & Projections". Under "Major Topics", select "Sales, revenue & prices"
  • Under Results, scroll down and open State Electricity Profiles (You'll need this table for the Lesson Activity)

 

Power Grid

Viewing Assignment

Watch video, How the grid works [10] (BURN [11]: Radio, The Public Radio Energy Project, 4:24 min)

The electricity power grid is the physical system that delivers electricity from the place where it is generated to the site where it is used.

Basic concepts:

  • The electricity leaving the generating station enters a sub-station with a step-up transformer that raises the voltage extremely high for long-distance transmission.
  • When electricity travels through a conductor (wires), some energy is lost. Less energy is lost when the electricity is at a higher voltage. At a higher voltage, nearly the same amount of power can be transmitted but at a lower current. The amount of energy lost from the conductor (line losses) is directly proportional to the current. The less the current, the less the losses.  Typically in the U.S., line losses between generation and end-use are in the 6% to 8% range.
  • The high-voltage electricity is carried over transmission lines to local substations where a step-down transformer reduces the voltage to levels suitable for customer loads. Distribution lines carry the lower-voltage electricity from the local substations to customer sites.
Diagram of the Electricity Power Grid. See link in caption for text version.
The Electricity Power Grid.
Text Version [12]
Credit: U.S. Department of Energy, Office of Electricity Delivery and Energy Reliability [13]

Reading Assignment

From Energy Explained, read How Electricity is Delivered to Consumers [14] (updated Dec 2016)

Simulation Assignment

The Power Grid is a simulation applet, developed at the University of Illinois in partnership with The Office for Mathematics, Science, and Technology Education (MSTE) in the College of Education and the Information Trust Institute.

  • Access the simulation applet The Power Grid [15].
  • Read the introduction paragraph.
  • BE SURE to follow note regarding browser compatibility.

User Guidelines

When the applet opens, power is being produced by four of the five generators. You can see the power moving from the generators through the substations and to the users in the Communities of Commerceton, Industryville, and Residenceburg.

Any power that is not used by the communities is sent to users in other systems. If the generators are not producing enough power, power will be purchased from other systems. In the applet this is indicated by the two External Systems. (This simulation is designed to blackout if both External Systems are disconnected from the system.)

The arrows show the direction the power is moving. The current is flowing out of the generators, through the substations and into the communities. Bigger arrows indicate more power.

The transmission lines in the applet have varying capacities. They range from 1000 MW to 2000 MW. The line flow for each line is noted near the line and changes as the power flow changes. (When a line is carrying less than 85% of its capacity, the arrows are green, indicating that the flows are within normal operating conditions. As the flow moves past 85% of the line capacity, the arrows turn orange, indicating that the lines should not be made to carry much more power. As the flow continues to increase past the maximum, the arrows turn red.) If a line remains overloaded for approximately 10 seconds, it automatically opens and a notification is displayed.

If a community demands more power than the transmission line that serves it can carry, the community will blackout. A community may also blackout if a line is damaged. In the applet as well as in reality, a transmission line problem in one area of the system can cause blackouts in several areas.

There are five generators represented in this simulation. The coal, hydropower and natural gas generators have adjustable outputs. The others do not. Click on the up and down arrows to the right of MW output labels to change the production.

While wind's output cannot be adjusted, its variation can be set from "none" to "High" using the slider below the system graphic.

All of the generators have connection switches that you can open or close.

 

Grid Management

Bottom Line

Electricity is not easily or efficiently stored in large amounts. In an electricity grid, power generation and power consumption must be closely matched at all times. These are key concepts in our understanding of electricity. If power generation and power consumption get out of balance, blackouts and other systemic failures occur.

Electricity must be produced on demand, as needed. Naturally, demand changes throughout each day and throughout the year. Demands are met with a combination of power plants that are used all the time (base load) and others that are used when needed to meet peak demand. Together, they must have the collective capacity to meet actual demand, real-time.

Large swings in demand are expensive and problematic. When demand is low, expensive generating facilities (built to meet peak requirements) are sitting offline idle. When demand is high, all available generators are online running full tilt, stressing the system and risking reliability. Reducing large swings in demand allows for the more cost and energy efficient design and operation of the electricity grid and its generators.

Demand Response

To achieve this balance, widespread efforts are being made to involve the consumer in the management of electricity demand. Overall, the umbrella term for working with customers to balance their electricity usage with the available supply is called demand response. The essential component is some form of communication with the customer or the customer’s systems so that they know when a change in their demand is desirable (supply is low, use less or supply is high, good time to use more). There are many ways to accomplish this using tools and methods described as demand-side management (DSM). Here’s the definition from our friends at EIA [16]:

"Demand-side management (DSM): A utility action that reduces or curtails end-use equipment or processes. DSM is often used in order to reduce customer load during peak demand and/or in times of supply constraint. DSM includes programs that are focused, deep, and immediate such as the brief curtailment of energy-intensive processes used by a utility's most demanding industrial customers, and programs that are broad, shallow, and less immediate such as the promotion of energy-efficient equipment in residential and commercial sectors."

Every dollar spent on DR can yield up to $4 in consumer benefits, a new AEE study finds

As the efficiency saying goes, the cheapest megawatt is the one we don't use. In demand response parlance, the most expensive megawatt is the last one we need.

Thanks in large part to Mother Nature and those pesky things called “seasons,” the United States' electric grid is built for capacity we almost never use. A new report from Advanced Energy Economy [17] (AEE) finds that 10% of the country's electric system is built to meet demand in just 1% of a year's hours. And reducing those demand peaks – typically met with the costliest, dirtiest electricity generation – can have a significant impact on consumers' bottom lines.

UtilityDIVE (Nov 5, 2015) [18]

Other terms related to this topic are load shifting and load leveling (both refer to rescheduling electricity usage to reduce peaks), time-of-day or time-of-use pricing or real-time pricing (customer is charged more for electricity used during peak periods) and smart grid, discussed next!

Grid Energy Storage

The Electricity Storage Association explains the importance of grid energy storage, "Energy storage funamentally improves the way we generate, deliver, and consume electricity. Energy storage helps during emergencies like power outages from storms, equipment failures, accidents or even terrorist attacks. But the game-changing nature of energy storage is its ability to balance power supply and demand instanteously - within milliseconds - which make power networks more resilient, efficient, and cleaner than ever before.' (Frequently Asked Questions [19])

We also know that electricity is not easily or efficiently stored in large amounts. The Electricity Storage Association identifies six categories of Energy Storage Technologies [20]:

  • Solid State Batteries: a range of electromechanival storage solutions, including advacned chemistry batteries and capacitors
  • Flow Batteries: batteries where the energy is stored directly in the electrolyte solution for longer cycle life and quick response times
  • Flywheels: mechanical devices that harness rotational energy to deliver instantaneous electricity
  • Compressed Air Energy Storage: utilizing compressed air to create a potent energy reserved
  • Thermal: capturing heat and cole to create energy on demand
  • Pumped Hydro-Power: creating large-scale reservoirs of energy with water

Primitive as it may seem, the grid-tied energy storage technology with the largest capacity is simply to pump water to a higher elevation, storing it as potential energy. Called pumped storage, or pumped hydro-power, the energy is recovered when the water from the higher elevation is used to drive turbines for hydroelectric power conversion.

The Electricity Storage Association [21] reports, "Because of the immense scale achieved through these applications, this is the most common type of grid-level energy storage based on megawatts installed today."

All in all, however, this process uses more electricity than it produces. So why do it? When a power plant has extra capacity, it generates electricity used to pump water uphill. Then, when the plant is stretched to capacity and electricity is at its highest price, this pumped storage can be used to generate low-cost hydroelectricity.

Reading Assignment

From the Tennessee Valley Authority,

  • Access the page Raccoon Mountain [22]. Read opening section and "Facts+Figures"
  • Access the page Raccoon Mountain Refill [23]. Read page and watch video (less than a minute!)

 

Smart Grid

Viewing Assignment

  • Visit PBS Nova [24] and watch Smart Grid. (It's about 9 minutes.)

Reading Assignment

  • Visit SmartGrid.gov [25] and read all sections (also watch short related videos).

 

Lesson 5 Activity

Complete the Lesson 5 Activity. (It's in CANVAS, under Modules, Unit 3.)

Unless noted otherwise, correct answers come directly from the content of this lesson and assigned readings.

The Activity consists of a variety questions of different types, which may include true/false, multiple choice, multiple select, fill in the blank, ordering, and short answer. The point value varies and is indicated for each. Some questions are graded automatically, and some are manually graded.

The quiz is not timed, but does close at 11:59 pm Eastern Standard Time on the due date as shown in CANVAS.

Questions that are "manually graded" will be scored based on the correctness and quality of your answers. Thinking is good! Try to make your answers as orderly and clear as possible. Short is good, as long as you fully answer the question. Help me understand what you are thinking, and include data where relevant.

Numbers must ALWAYS be accompanied by units of measure (not "300" but "300 kW").

Proofread and spell check your work.

Discussion Forum

Unit 3 Discussion Forum: "Smart Grid"

A report from the White House presents estimates of weather-related power outages costing the US economy $25 to $70 billion a year (inflation adjusted). These costs include lost output and wages, spoiled inventory, delayed production, inconvenience, and damage to the grid itself. Severe weather is the "number one" cause of power outages in the United States and the number of outages caused by severe weather is "expected to rise as climate change increases the frequency and intensity of hurricanes, blizzards, floods and other extreme weather events." (Economic Benefits of Increasing Electric Grid Resilience to Weather Outages [26], Executive Office of the President, August 2013.)

Power failures are expensive, disruptive, and can be dangerous. After no significant power losses for a decade, our home has been without power for weeks over the last several years, a result of changing weather and aging infrastructure--freak ice storms, Sandy, local equipment failure. All events were costly in terms of work productivity, loss of property and expensive emergency measures to find safe and warm temporary housing. Compounding the misery, like many, we received poor or no information about the status of our service, and the info we did receive was often very wrong. We received numerous calls from the utility and even a visit from a worker to tell us our service was restored when the street was still lined with downed poles. (Can you imagine THAT conversation?) I'm sure many of you have your stories too!

One possible remedy to help prevent and then manage before, during and after grid failures is the smart grid. Recent events, like severe winter weather and Hurricane Sandy, have drawn attention again to the Smart Grid. The promise of its benefits are beyond mitigation of power outages; however, it may also help us use energy more efficiently through information and personal behavior as well as automation and intelligent controls. The Smart Grid could also help integrate distributed generation smoothly into the grid, especially important for intermittent renewable energy sources such as solar and wind. ("Distributed generation" simply means the electricity is generated at or near its point of use.)

In this discussion, we'll talk about what the smart grid is, its promises and challenges and what it may mean to you.

Use material from the lesson and your own independent research. In your posting, please address the following:
  • In your own words, briefly describe what the smart grid is.
  • Ask someone in your everyday life to describe the Smart Grid. How did they do? (Tell us!) How well do you believe the public understands what the smart grid is?
  • Research and share one new piece of information about the smart grid (not something covered in the lesson). Please give source, of course.
  • What do you see as the two most promising features (benefits) of the smart grid to society? What do you see as the biggest challenges?
  • How do you think the smart grid would be of benefit to you directly? What, if anything, about the smart grid might concern you, worry you, personally?
Respond. Read the postings of others and respond to at least one.

Please define and explain any acronyms or abbreviations you use (GHG = greenhouse gas) and wherever possible include links to your references. Any questions, just let me know!

Post your work in the Discussion, "Smart Grid" You'll find it in CANVAS, in the Unit 3 Module.

Read the postings of others and respond to at least one. Follow up on any postings made to your comment.

Please see CANVAS calendar for due date of your FIRST posting and date when discussion ends (graded participation ends, all replies must be in).

Grading criteria

You will be graded on the quality of your participation. Be interesting and interested! Please see Syllabus for full Discussion grading criteria.

 

Summary and Final Tasks

Summary

In this lesson, you learned about electricity demand, domestically and worldwide, and put these values in the context of relative population. You learned about the power grid, the major components of its infrastructure and governance, and issues related to grid management, including the Smart Grid.

Reminder—Complete all of the lesson tasks!

You have finished Lesson 5. Double-check the list of requirements on the Lesson 5 Overview page to make sure you have completed all of the activities listed there before beginning the next lesson.


Source URL: https://www.e-education.psu.edu/egee401/content/p5.html

Links
[1] http://www.worldenergyoutlook.org/
[2] http://www.iea.org/
[3] http://www.worldenergyoutlook.org/aboutweo/
[4] http://www.libraries.psu.edu/psul/home.html
[5] https://www.oecd.org/about/membersandpartners/
[6] http://tonto.eia.doe.gov/abouteia/mission_overview.cfm
[7] http://www.eia.gov/forecasts/aeo/appendixe.cfm
[8] http://www.eia.gov/forecasts/aeo/chapter_intro.cfm
[9] http://www.eia.doe.gov/
[10] https://www.youtube.com/watch?v=1dZjohZPIqE#t=128
[11] http://burnanenergyjournal.com/about-burn/
[12] https://www.e-education.psu.edu/egee401/sites/www.e-education.psu.edu.egee401/files/image/lesson05/BetterGrid_LD.html
[13] http://energy.gov/oe/office-electricity-delivery-and-energy-reliability
[14] http://www.eia.gov/energyexplained/index.cfm?page=electricity_delivery
[15] https://credc.mste.illinois.edu/applet/pg
[16] http://www.eia.doe.gov/glossary/glossary_d.htm
[17] http://info.aee.net/peak-demand-reduction-report
[18] http://www.utilitydive.com/news/the-value-of-less-quantifying-the-benefit-of-peak-demand-savings/408565/
[19] http://energystorage.org/energy-storage/faq
[20] http://energystorage.org/energy-storage/energy-storage-technologies
[21] http://energystorage.org/energy-storage/energy-storage-technologies/pumped-hydro-power
[22] https://www.tva.gov/Energy/Our-Power-System/Hydroelectric/Raccoon-Mountain
[23] https://www.tva.com/Environment/Raccoon-Mountain-Refill
[24] http://www.pbs.org/wgbh/nova/tech/power-grid.html
[25] http://www.smartgrid.gov/the_smart_grid#smart_grid
[26] http://energy.gov/sites/prod/files/2013/08/f2/Grid%20Resiliency%20Report_FINAL.pdf