|Fig. 1: US Energy Consumption by Energy Source, 2015.  (Courtesy of the EIA)|
For the past several hundred years, our society has seen major shifts in energy consumption. In recent years, the United States made up roughly 18% of the world's energy supply, and according to Fig. 1 on the right, 80% of energy consumption in the US came from fossil fuels in the form of oil, coal, or natural gas.  While these fossil fuels are currently much more effective and efficient than other resources such as renewables, they are not a long-term sustainable option. Their disadvantages in relation to their finite supply, political turmoil, and negative environmental impact have proven that our society must seek alternative energy resources in order to build a sustainable future. Thus, it is important to understand how the United States currently produces, stores, and uses energy, and subsequently outline opportunities for emerging energy technologies to see what our energy system might look like in 2060. 
In 2012, the US produced roughly 95.1 quads of energy (1 quad = 1 quadrillion BTU = 1.055 × 1018 joules), with fossil fuels producing 78.1 quads of that (petroleum: 34.7 quads, natural gas: 26.0 quads, coal: 17.4 quads).  Although there are several alternatives to fossil fuels, there are many reasons as to why fossil fuels have been such an appealing energy source. Not only are they incredibly abundant, providing almost 30% of global energy, but their high energy and power density can power anything from personal vehicles to large aircrafts and allow users to travel for hundreds of miles on a single tank of gas. In addition, its current low cost and ease of use make them all the more appealing, as users can pump their gas tanks in a matter of minutes. 
Even though fossil fuels have proven to be an invaluable resource for many years, issues in regards to supply, national security, price volatility, and environmental impact make them unsustainable for the long-term. The amount of global fossil fuel reserves is rapidly fading, with roughly 892 billion tons of coal, 186 trillion cubic meters of natural gas, and 1,688 billion barrels of crude oil. These values may seem large at first glance, but current trends suggest that reserves of coal would be exhausted by the year 2129, the last cubic meter of natural gas used by 2069, and all of crude oil gone by 2067. 
Another drawback of fossil fuels is that because they are are finite and unevenly distributed, the competition to accrue them inevitably results in a zero-sum game causing geopolitical turmoil. Fossil fuels reserves are controlled by states rather than third-party companies and so these states can exert significant influence over their consumers. Many argue that because United States foreign policy is readily dependent on fossil fuels due to the incredible amount of energy we output on a yearly basis, the country has often times bowed down to authoritarian regimes, ultimately causing a decline in its world reputation and increasing military involvement. 
The dwindling supply and geopolitical turmoil of fossil fuels has led to a third problem - price volatility. Oil prices are primarily driven by market speculation caused by global events and thus are incredibly unpredictable. In the past several years, crude oil has fluctuated between $30 per barrel to $140 per barrel, making the future of oil prices difficult to sustain.
While there are several emerging energy technologies, a source of energy that could play a big role in energy production in the future is just emerging - nuclear fusion. Nuclear energy in the United States has been around since the 1950s, with almost 10% of the country's energy coming from 100 nuclear power plants.  Today's nuclear energy comes from a process known as nuclear fission, in which unstable atoms are split into pieces, ultimately releasing energy throughout the process. While efficient and inexpensive to operate, nuclear fission can result in significant amounts of radioactive waste disposal and safety concerns, such as the recent accident in Fukushima, Japan.
Yet, nuclear fusion is a promising alternative that is slowly being developed by scientists and engineers around the world. Essentially, nuclear fusion is the most basic form of energy, used by the sun and stars in our galaxy. Over the past several years, billions of dollars have been invested into nuclear fusion, a synthetic process in which two gases - deuterium and tritium - are heated to extremely hot temperatures causing the gases to transform into plasma and release great amounts of heat. Once implemented, the process of nuclear fusion is inexpensive, environmentally friendly, and limitless. The amount of energy released in fusion is 10 million times greater than the burning of fossil fuels. In addition, nuclear fusion is much easier to control than fission because there is no chain reaction, ultimately making the process safer. 
All in all, by understanding current trends in the way that the US produces, stores, and uses energy, we are able to make predictions as to what energy might look like in 2060. Even though fossil fuels remain prevalent in our energy sectors, it is imperative to realize that they cannot be sustained as long-term resources. By identifying alternative sources of energy, such as nuclear fusion, we can attempt to break free from our usage of fossil fuels in order to live in a more sustainable world. The energy of the future comes with many obstacles that we must overcome, yet our long-term success will come from our own knowledge rather than our reliance on resources.
© Mitchell Kogan. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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