The Early Morning Light

Before diving into the motivation and science behind my research I first want to provide some broader context for the use of renewable energy technologies, solar specifically, in the U.S. Many of these technologies still have a long way to go before they can carry any real weight with respect to our energy usage. As you will soon see, it is not a simple matter of swapping solar for this or that. I will present some data, and comments, on energy use in the US to better illustrate some of the very real challenges to make solar a more prominent technology in our lives.

US Energy Consumption by Source

All of the following charts were generated through the website of the U.S. Energy Information Administaton (EIA).¹ The first chart below is the total, annual U.S. energy consumption from 1949 to 2015.

At first it looks like we’re doing pretty well² with renewable energy, but notice how little it has changed over the past 65 years compared to the other sources. Now realize that “Renewable” is not all solar, it is a mixture of sources. Let’s see what that looks like.

It becomes apparent that this category is actually dominated by hydroelectric power and biomass. You can see an increase in solar over the past decade or so (wind even more so) but it is washed out on this scale. Let’s “zoom in” again.

We have seen a significant increase in solar, especially over the past 5 years, and this is primarily due to cost reductions.³ Let us not forget where we came from to get to this chart. How does solar alone compare against the rest of our energy consumption? Here is the same chart we started with but we are only showing the solar portion of “Renewable Energy.”

Clearly it is not the biggest piece of the pie⁴. How big is its actual “slice” compared to the whole thing?

Hard to assign it any vale besides “almost zero”. Here is a quick energy breakdown:

Total US Energy Consumption in 2015: 97.3 quadrillion⁵ British Thermal Units (BTUs)

Total US Renewable Energy Consumption in 2015: 9.56 quadrillion BTUs (9.8% of total US consumption)

Total US Solar consumption in 2015: 0.431 quadrillion BTUs (4.5% of renewables, 0.44% of total)

That’s right, in 2015 solar energy only amounted to 0.44% of our total energy usage. Before I further comment on that let’s have a little fun with the data.⁶ Instead of looking at how much energy came from this source or that source, let’s explore the sheer amount of energy that was used in the first place.

Unit Conversions! AKA “How Much Energy is That Anyway?”

What does 97.3 quadrillion BTUs, for total US energy consumption (in 2015), even look like?

1 calorie, the same calorie you look at on your food labels,⁷ is the amount of energy to raise 1 gram (a cubic centimeter) of water by 1 degree Celsius. Ok, so what?

That means if you used every BTU we consumed last year you could boil (from 68 degrees F) roughly 306 cubic kilometers (73 cubic miles) of water!⁸

How much water is that? You could boil Lake Champlain 12 times or Crater Lake 16 times or 64% of Lake Erie!

What This Means for Me?⁹

Even as a researcher in the field I sometimes forget to put it all in perspective. Most people seem to get very excited, or at least supportive, when I tell them I am doing solar related research. While the motivations may differ from time to time, I frequently hear about the need to expand the use of, and infrastructure for, renewable technologies.¹⁰ However, I think it is important to realize what “more” renewable energy looks like to fully appreciate the challenge of getting there.

As I mentioned in the beginning, it is not a simple matter of swapping solar for this or that because there is so much of “this” AND “that.” Even though a “breakthrough” in solar research could take decades, if not a century, to handle a significant fraction of that energy pie we eat each year I still believe it is worth it for some of us to participate in that endeavor. I believe in the sentiment of my advisor, Dr. Shannon Boettcher,¹¹ that it will take the collective effort of many people, over time, to make a real difference with this technology (or any other for that matter) but the fact that it could make a difference and is the right thing to do is what makes it worth it.

Why am I doing what I am doing for my research? Because I want to contribute to a solution instead of waiting for it to happen. What I am doing for my research will come later.