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Energy Within Environmental Constraints

Professor David Keith, Daniel Thorpe, Harvard University
Contact instructors by posting to the discussion boards with [STAFF] in the title of your post

Course active June 8 - August 17 2016
This course exclusively uses UTC time
Assignments due at 11:30 pm (UTC) on Sundays each week
See the Google Calendar and Schedule for important dates

This clock shows the current time in UTC:

Course Overview

Humanity faces an immense challenge: providing abundant energy to everyone without wrecking the planet. If we want a high-energy future while protecting the natural world for our children, we must consider the environmental consequences of energy production and use. But money matters too: energy solutions that ignore economic costs are not realistic—particularly in a world where billions of people currently can't afford access to basic energy services. How can we proceed?

Energy Within Environmental Constraints won't give you the answer. Instead, we will teach you how to ask the right questions and estimate the consequences of different choices.

This course is intended for a diverse audience. Whether you are a student, an activist, a policymaker, a congressional staffer or NGO employee, a business owner, or a concerned citizen, this course will help you start to think carefully about our current energy system and how we can improve its environmental performance.

This course...

  • Covers engineering, environmental science, and economics to enable critical, quantitative thinking about our energy system.
  • Focuses on a working understanding of energy technologies, rich in details of real devices and light on theory; you won't find any electrodynamics here but will find enough about modern commercial solar panels to estimate if they would be profitable to install in a given location.
  • Covers environmental impacts of the energy system, focusing on air pollution, climate change, and land use.
  • Emphasizes costs: the cascade of capital and operating costs from energy extraction all the way through end uses.
  • Emphasizes quantitative comparisons and tradeoffs: how much more expensive is electricity from solar panels than from coal plants, and how much pollution does it prevent? Is solar power as cost-effective an environmental investment as nuclear power or energy efficiency? And how do we include considerations other than cost?

Please note that this is an abridged course, equivalent to roughly half of a full semester-long undergraduate course. See the Course Schedule for topics that we include and a list of some we exclude.

You will learn...

  • How energy flows through modern economies, from initial resources to end users.
  • The environmental impacts of today's energy system, focusing on air pollution, climate, and land use.
  • How to estimate economic costs of reducing environmental impacts.
  • Details on nuclear and solar power: technology, costs, policy, unique challenges and problems.
  • How to critically compare energy options, including quantitative and qualitative analysis.


To get the most out of this course you should be familiar with chemistry and physics at the high school level, as well as basic algebra.

That said, the majority of the course is accessible to anyone. For example, even if you don't understand our descriptions of how solar panels work, you can still follow much of the discussion on solar subsidies.

Course Terminology and Components

Section: the major, weekly segments of the course, e.g. "Energy System Overview" (week 2), and "Electric Grid" (week 6).

Subsection: the major sub-topics in each Section, e.g. within the "Electric Grid" Section the segments titled "How the Electric Grid Works Today" and "History and Future of the Electric Grid." Subsections usually include several video lectures, readings, and assignments.

Unit: the components that make up a Subsection. Units usually only have a few video lectures, readings, or assignments.

Shows where sections, subsections, and units are on the screen

Video Lecture: a video lecture for you to watch, usually 5-10 minutes long.

Reading: required reading written by the instructors, usually with a few associated questions or assignments.

External Reading: required reading outside of the edX platform, e.g. when you read some NYT articles before writing an essay; we provide hyperlinks.

Assignments: graded or ungraded work for you to do; see the Grading section below for details.

References and Deep Dives: at the end of each Section we list our references for facts in videos and readings, and provide "deep dives," our recommended resources for learning more about a topic; these are organized by topic.

Grading & Certification

This course has three types of assignments for students. There are no quizzes, tests, or exams. Different students will see different versions of many questions.

"Coursework" [80% of final grade]: This category covers the majority of problems in the course. Some are brief questions to pique your interest, survey what you know before starting a topic, or ensure that you understood the most critical points from a lecture or reading. At the higher end, these are lengthier questions or groups of questions that ask you to apply course concepts, analyze, calculate, and/or look up data from outside sources.

"Practice" [0% of final grade]: This category is used for questions that we encourage you to answer, but which do not impact your grade. Some are solely for practice purposes, others help us to know where you are in your understanding and improve our course in the future.

"Peer Graded" [20% of final grade]: There are several essays in this course, ranging from ~300 to ~1000 words. They are the pinnacle of the most important sections of the course, giving you a place to synthesize the information and skills you've learned, evaluate different positions on controversial issues, and develop your own views on how we should reform our energy system. They are peer-graded: you will grade 4 peers' essays using a detailed rubric, and your own grade will be the average of the grades your peers give you.

You will be able to see the answers to all questions after the due date has passed.

Passing the course, and certification

The passing grade for this course is 60% (using the weights above).

If you register for a Verified Certificate, and your score is 60% or above, you will receive a certificate. Certificates will be issued automatically by edX upon course completion, and will appear on your Dashboard page roughly two weeks after the course ends. They are not mailed to you. The final day to sign up for a verified certificate is July 29th.

Guidelines For Collaboration

We encourage class participants to collaborate on assignments! But be sure you learn how to do the assignments yourself, and please do not post solutions to discussion forums until after the due date. Staff will proactively remove solutions posted before due dates.

  • It is OK to discuss or work jointly to develop a general approach to an assignment.
  • It is OK to get a hint from peers or course staff if you get stuck on an assignment.
  • You should work out the details of assignments yourself.
  • It is not OK to copy someone else's solution.
  • It is not OK to take someone else's formula and plug in your own numbers to get the answer.
  • It is not OK to post answers to a problem before the submission deadline.
  • It is not OK to look at a full step-by-step solution to a problem before the submission deadline.

Discussion Forums

We encourage you to use the course Discussion Forum! It has many uses, and we'll prompt you to participate throughout the course.

Some good uses of the Discussion Forum:

  • Asking questions about course content and assignments.
  • Collaborating appropriately on assignments.
  • Contacting course staff.
  • Starting discussions related to course content.
  • Commenting on course content, including giving the instructors feedback, disagreeing with us, or suggesting improvements.

Our discussion forum guidelines

  • Be polite and encouraging.
  • Work together and work independently.
  • Post hints rather than answers. If you're not sure where to draw the line, follow the collaboration guidelines.
  • You can and should discuss questions, consider possibilities, and ask for hints.
  • You should not request or give out answers, even answers that you know are wrong. You can talk about the answers after the deadlines pass.
  • Use your vote. If you agree with what someone says, don't write a post. Just click the plus button!
  • Tag your posts. If there is an issue that absolutely needs staff attention, put the word [STAFF] in brackets in your subject line. Course staff will be in the forums every day, but it may take up to two days to get a response sometimes, especially around holidays.


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