The generation of electrical, mechanical, and thermal power has always been interesting to me, since it underlies so much of the advancement, strength, and health of our societies. There has been a lot of fear and hope recently in the world and the U.S. regarding how the use of energy affects jobs, imports/exports, development, and the environment. What I’m starting to realize after being in the energy field for several decades is that renewable technologies have finally evolved to the point where a myriad of them can be very competitive with the classic baseload  plants (such as coal and nuclear), and the pace of this evolution has been dazzlingly swift in the past few years, so much that it’s caught me a bit by surprise. As a result, the outlook for new engineers entering energy-related careers might be changing swiftly as well.

This post was in part spurred by a presentation I gave in the Caribbean recently. The presentation had a figure showing levelized costs of electricity (LCOE) of various technologies, and the study was from 2014. I really liked how the figure was composed, and figured that even though it was a year or two old, it would be close enough for what I was trying to convey. However, after the presentation one of the attendees (politely) told me that the value for solar photovoltaics (PV) was out of date. I agreed and promised to myself that I would do a deeper survey of these trends and consider how they might be affecting our energy outlooks.

So what has the U.S. energy mix used to produce electricity looked like over the years, how is this changing, and what might it imply? Let’s start with how things have changed since 2001 – not so very long ago. This table using data from the U.S. Energy Information Administration (EIA) and commentary will get a little wonky and long but please bear with it. It shows U.S. annual electricity production, characterized by fuel source.

Generation TypeUnits2001200520102015
Coal and petroleumthousand GWh2,0292,1351,8841,381
% of total54%53%46%34%
Average annual change in thousand GWh, 2001-2015-65
Natural gas and other gasesthousand GWh6487749991,347
% of total17%19%24%33%
Average annual change in thousand GWh, 2001-201556
Nuclearthousand GWh769781807797
% of total21%19%20%20%
Average annual change in thousand GWh, 2001-20150.8
Hydro and pumped storagethousand GWh208264255244
% of total6%7%6%6%
Average annual change in thousand GWh, 2001-2015-1
Other renewables and miscthousand GWh83100180309
% of total2%2%4%8%
Average annual change in thousand GWh, 2001-201519

 

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