U.S. energy transitions in one graph

Join Our Community of Science Lovers!

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


To understand what the future of United States’ energy mix will look like in the future, it’s useful to look back at its energy history. This one graph from the U.S. Energy Information Administration tells us a lot about how we have consumed energy in this country:

There are three themes that run through U.S.’s energy history:

  • We go through energy transitions regularly, largely out of necessity (running out of forests or whale oil (Peak Whale) or with the discovery of a better fuel source;

  • We tend to diversify our fuel mix as time goes on (again, finding new, better fuel sources) by adding new fuel sources more than we retire fuel sources;

  • We tend to decarbonize as time goes on (from carbon-intensive wood to coal to petroleum to natural gas).


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


The twentieth century saw an explosion of fuels: natural gas was heavily developed, coal reemerged as an electric fuel source, nuclear fission was harnessed for electricity generation while renewables like solar, wind, and hydro grew as well.

We can make an informed guess about the future of the U.S. energy mix and assume that these three themes will continue. It’s likely that we will continue to decarbonize (which we are seeing some with fuel switching to natural gas from coal and an increase in renewables, notably wind generation).

As for the first bullet point, there is an important nuance between past transitions and present day. The impetus to fuel switch was more observable in many cases in the past; one could look out and see a dwindling supply of trees in a forest, or run out of whales.

Energy transitions driven by climate change and carbon emissions are based mostly on indirect observations or anticipated outcomes (rising sea levels, melting glaciers, insects and other biological proxies), rather than, say, stepping outside and “seeing” more carbon in the atmosphere.

David Wogan is an engineer and policy researcher who writes about energy, technology, and policy.

David's academic and professional background includes a unique blend of technology and policy in the field of energy systems. Most recently, David worked at Austin Energy, a Texas municipal utility, implementing a Department of Energy stimulus grant related to energy efficiency. Previously, David was a member of the Energy & Climate Change team at the White House Council on Environmental Quality for the Obama Administration.

David holds two Master's degrees from The University of Texas at Austin in Mechanical Engineering and Public Affairs. While at UT, David was a researcher in the Webber Energy Group, where his research focused on advanced biofuel production to offset petroleum use in the transportation sector. David holds a Bachelor's of Science degree in Mechanical Engineering from The University of Texas at Austin, where he researched nuclear non-proliferation measurement technology.

David is a 2013 Aspen Institute Journalism Scholar, joining a select group of journalists from Slate, ABC News, and The New York Times.

David lives in Austin, Texas. Follow along on Twitter or email him at david.wogan@me.com.

More by David Wogan

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe