U.S. Energy Yesterday, Today, and Tomorrow

U.S. Energy Yesterday, Today, and Tomorrow

By Fred Abernathy, School of Engineering and Applied Sciences, Harvard University.
Chapters from a book in progress. 2016.

PowerlinesThe U.S. has an energy system of the colossal size needed to provide our homes, commercial buildings, and factories with all the electrical energy demanded by our activities. Our demand for cars and general transportation on the ground and in the air requires gasoline, diesel, and jet fuel to be available when needed, in sufficient quantity to satisfy demand. To produce them, primary fuels must be burned and crude oil must be chemically refined.

These chapters focus on the consumption of electrical energy in the residential setting in Chapter 2, and the importation of petroleum products compared with our U.S based production and its subsequent consumption in transportation in our economy in Chapter 3. Chapter 4—in preparation—will deal with thermal insulation of existing homes and new standards for new homes and major renovations.

To keep our economy humming along we consume very large quantities of nine primary fuels; the smallest quantity of primary energy we consume is solar, and petroleum is the largest quantity. In Chapter I, all of the primary fuels are described, along with their percentage contribution to our overall energy consumption for the 2010 base year, and the common units used to describe the quantities of energy are defined. All primary forms of energy are quantified in the same units of energy, so quantity comparisons of different forms of energy are obvious.

The intended readers of this book are homeowners who are interested in learning what they might do, and why, to keep their current level of home convenience but decrease their monthly energy bills or decrease their carbon footprint. They also must not be adverse to looking at tables and graphs of data, and doing a little bit of arithmetic here and there.

The vast majority of the primary energy, a bit over 2/3 of the primary energy in 2010, went into just two uses, namely the generation of electrical energy and transportation. About 40 per cent of U.S. primary energy is consumed to generate electrical energy, an intermediate form that is the most versatile form of energy. Our residences consume more electrical energy than do the commercial or industrial sectors. The story of how technological improvements in electrical appliances have led to the plateauing of demand for electrical energy in residences is developed in Chapter 2. Improved technology has allowed us to satisfy our demand for lighting, refrigeration, air-conditioning, computers, and TVs while consuming less energy. Looking back to the decade 1995 to 2005, before much of the new technology was in use, net electrical energy generated nationally grew by 21 per cent, a bit over 2 per cent per year. And in the decade from 2005 to 2015, the yearly electrical energy consumption from the grid has been essentially constant even though economic activity has increased and the population has grown. Energy efficient technology has to be the primary reason for the rather sudden plateau of electrical use in commerce and in industrial.

The U.S has been a net importer of crude oil and other petroleum products since soon after World War II. Chapter 3 discusses both our imports and exports of petroleum products. Our national imports of crude oil reached a peak of 10.1 million barrels per day in 2005, decreasing to 7.3 million barrels per day in 2014. This drop in imports and expansion of our exports from 1.2 million barrels per day in 2005 to 4.2 million barrels per day in 2014 is due to the development and deployment of new U. S. based drilling technology in the last decade—horizontal drilling and fracking in deep shale formations. Chapter 3 also reveals that our consumption of automobile gasoline, diesel fuel, and jet fuel has declined only slightly since the 2005 peak year.

In addition, Chapter 3 tells of the agreement between the Federal Government and almost all of the manufacturers of cars and light duty vehicles to dramatically increase the CAFÉ standards that would also make allowance for vehicle footprint when setting miles-per-gallon goals. New spark engine technology, lighter and stronger bodies, and hybrid vehicles and all-electric vehicles are making it possible to increase the fuel efficiency of the new vehicle fleet. The recent drop in gasoline prices because of worldwide oversupply of crude oil has influenced the U.S new vehicle market, and buyers have shifted to light duty vehicles such as pickup trucks, crossovers, and SUVs and away from cars. The new car fleet will likely have a burst of efficiency as new all electrical cars with extended range and lower purchase costs enter the market.

PDFs of chapter drafts: Download Chapter 1 | Download Chapter 2 | Download Chapter 3

Note: These chapters are for reference only and are copyrighted by Frederick H. Abernathy, with the exception of those things which are already in the public domain.


If you have read the three chapters, I would appreciate your feedback by emailing me the answers to the following questions:

1. Did you learn anything useful for your plans for future energy use? 

2. Were you bothered by the extent of details? 

3. What information is missing that would be of interest to you?


U.S. Energy Use Charts

The energy flow diagrams provide information about the sectors of the economy that consume primary energy and estimate the efficiency of the conversion of primary forma of energy into useful activity as propelling a car or consuming national gas, coal, and other primary forms of energy  and generating electricity and distributing the electrical energy to the final consumer.

Download pdf of 2010-2014 U.S. energy use diagrams*

* Courtesy of the Lawrence Livermore National Laboratory.

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