1 Introduction

Revised 5/5/10
1.1 Energy and Society
1.2 Types of Energy
1.3 Renewable Energy
1.4 Advantages/Disadvantages
1.5 Economics
1.6 Global Warming
1.7 Order of Magnitude Estimates
1.8 Growth (Exponential)
1.9 Solutions

1.1 Energy and Society

    Industrialized societies run on energy, a tautological statement or an oxymoron in the sense that it is obvious. Population, gross domestic product (GDP), consumption and production of energy, and production of pollution for the world and the United States are interrelated. The United States has less than 5% of the world population, however it generates around 25% of the gross production, 22% of the carbon dioxide emissions and is at 22% for energy consumption (Fig. 1.1). Notice that the countries listed in Figure 1.1 consume around 75% of the energy and produce 75% the world GDP and carbon dioxide emission. Because population has increased and the amount of energy per person has also increased in the developed countries, the developed countries consume the most energy and produce the most pollution. On a per person basis, the United States is the worst for energy consumption and carbon dioxide emitted.

Figure 1.1 Major countries in terms of population (rank), gross domestic production, energy consumption, and carbon dioxide emissions, 2008.
Figure 1.1 Major countries in terms of population (rank), gross domestic production, energy consumption, and carbon dioxide emissions, 2008.

    The energy consumption in the United States increased from 32 Quads in 1950 to 101 Quads in 2008. One Quad = 1015 British Thermal Units (discussed in Ch. 2). There was an increase in efficiency in the industrial sector, primarily due to the shock of the oil crisis of 1973. However you must remember that correlation between gross domestic production (GDP) and energy consumption does not mean cause and effect. The oil crisis of 1973 showed that efficiency is a major component in gross national product and the use of energy.

    It is enlightening to consider how the United States has changed in terms of energy since World War II. Ask your grandparents about their lives in the year 1950 and then compare with your family today.
    A thought on energy and GDP: A solar clothes drying (a clothes line) does not add to the GNP, but every electric and gas dryer does. They both do the same function. We may need to think in terms of results and efficient ways to accomplish that function or process. Why do we need heavy cars or SUVs that accelerate rapidly to transport people?

    Now the underdeveloped part of the world, primarily the two largest countries in term of population (China 1.3 * 109 and India 1.1 * 109), is beginning to emulate the developed countries in terms of energy, material resources, and emissions. One dilemma in the developing world is that a large number of villages and others in rural areas do not have electricity.

1.2 Types of Energy

    There are many different types of energy. Kinetic energy is energy available in the motion of particles, for example wind or moving water. Potential energy is the energy available because of the position between particles, for example water stored in a dam, the energy in a coiled spring, and energy stored in molecules (gasoline). There are many examples of energy; mechanical, electrical, thermal (heat), chemical, magnetic, nuclear, biological, tidal, geothermal, and so on.

    In reality there are only four interactions (forces between particles) in the universe; nuclear, electromagnetic, weak, and gravitational [1]. In other words all the different types of energy in the universe can be traced back to one of these four interactions. This interaction or force is transmitted by an exchange particle. The exchange particles for electromagnetic and gravitational interactions have zero rest mass and with this comes the speed limit of light, 3*108 m/s (186,000 miles/second) for transfer of energy and information. Even though the gravitational interaction is very very very weak, it is noticeable when there are large masses. The four interactions are a great example of how a scientific principle covers an immense amount of phenomena.

Interaction Particle Strength Range, m Exchange Particle
Nuclear (strong) Quarks 1 10-15 Gluons
Electromagnetic Charge 10-2 Infinite Photon
Weak Leptons 10-6 10-18 "Weakons"*
Gravitational Mass 10-39 Infinite Graviton

    * Vaughn Nelson's name for exchange particles (intermediate vector bosons).

    The source of solar energy is the nuclear interactions at the core of the sun, where the energy comes from the conversion of hydrogen nuclei into helium nuclei. This energy is primarily transmitted to the earth by electromagnetic waves, which can also be represented by particles (photons). In this course we will be dealing primarily with the electromagnetic interaction, although hydro and tides are energy due to the gravitational interaction and geothermal energy is due to gravitational and nuclear decay.

1.3 Renewable Energy

    Solar energy is referred to as renewable and/or sustainable energy because it will be available as long as the sun continues to shine. Estimates for the life of the main stage of the sun are another 4 to 5 billion years. The energy from the sun, electromagnetic radiation, is referred to as insolation. The other main renewable energies are wind, biomass, tides, waves, geothermal and hydro. Wind energy is derived from the uneven heating of the earth's surface due to more heat input at the equator with the accompanying transfer of water by evaporation and rain. In this sense, rivers and dams for hydro energy are stored solar energy. The third major aspect of solar energy is the conversion of solar energy into biomass by photosynthesis. Animal products such as oil from fat and biogas from manure are derived from solar energy. Tidal energy is primarily due to the gravitational interaction of the earth and the moon. Another renewable energy is geothermal, due to heat from the earth from decay of radioactive particles. Volcanoes are fiery examples of geothermal energy reaching the surface from the interior, which is hotter than the surface.

    Overall 14% of the world's energy comes from biomass, primarily wood and charcoal, but also crop residue and even animal dung for cooking and some heating. This contributes to deforestation and the loss of topsoil in developing countries. Production of ethanol from biomass is now a contributor to liquid fuels for transportation, especially in Brazil.

    In contrast, fossil fuels are stored solar energy from past geological ages. Even though the quantities of oil, natural gas, and coal are large, they are finite and for the long term of 100s of years they are not sustainable.

    1.4 Advantages/Disadvantages

    The advantages of renewable energy are: sustainable (non depletable), ubiquitous (found everywhere across the world in contrast to fossil fuels and minerals) and essentially non-polluting. Note that wind turbines and photovoltaic panels do not need water for the generation of electricity, in contrast to steam plants fired by fossil fuels and nuclear power.

    The disadvantages of renewable energy are: variability and low density. In general this results in higher initial cost. For different forms of renewable energy, other disadvantages or perceived problems are visual pollution, odor from biomass, avian and bat mortality with wind plants, and brine from geothermal. I am sure that wherever a large renewable facility is to be located there will be perceived and real problems to the local people. For conventional power plants using fossil fuels, for nuclear energy, and even for renewable energy there is the problem of not in my backyard.

    1.5 Economics

    Business entities always couch their concerns in terms of economics. We cannot have a clean environment because it is uneconomical. Renewable energy is not economical in comparison to coal, oil and natural gas. We must be allowed to continue our operations as in the past, because if we have to install new equipment, we cannot compete with other energy sources. We will have to reduce employment, jobs will go overseas, etc.

    The different types of economics to consider are pecuniary, social, and physical. Pecuniary is what everybody thinks of as economics, DOLLARS. On that note, we should be looking at life cycle costs, rather than our ordinary way of doing business, low initial costs. Life cycle costs refer to all costs over the lifetime of the system.

    Social economics are those borne by everybody and many businesses want the general public to pay for their environmental costs. A good example is the use of coal in China, as they have laws (social) for clean air, but they are not enforced. The cost will be paid in the future in terms of health problems, especially for the children today. If environmental problem(s) affect(s) someone else today or in the future, who pays? The estimates of the pollution costs for generation of electricity by coal range from $0.005 to 0.10/kWh

    Physical economics is the energy cost and the efficiency of the process. There are fundamental limitations in nature due to physical laws. In the end Mother Nature always wins or the corollary, pay now or probably pay more in the future. Energetics, which is the energy input versus energy produced for any source, should be positive. For example production of ethanol from irrigated corn has close to zero energetics.

    Finally, we should look at incentives and penalties for the energy entities. What each entity wants are subsidies for themselves and penalties for their competitors. Penalties come in the form of taxes, environmental and other regulations, while incentives come in the form of subsidies, break on taxes, do not have to pay social costs on their product, and the government pays for research and development. How much should we subsidize businesses for exporting overseas? It is estimated that we use energy sources in direct proportion to the incentives that source has received in the past. There are many examples of incentives and penalties for all types of energy production and use.

    1.6 Global Warming

    Global warming is a good example that physical phenomena do not react to political or economic statements. Global warming is primarily due to human activity. “Global atmospheric concentrations of carbon dioxide, methane and nitrous oxide have increased markedly as a result of human activities since 1750 and now far exceed pre-industrial values determined from ice cores spanning many thousands of years  (see Figure SPM.1). The global increases in carbon dioxide concentration are due primarily to fossil fuel use and land use change, while those of methane and nitrous oxide are primarily due to agriculture.” [2, 3] Concentrations of carbon dioxide in the atmosphere (Fig. 1.2) are projected to double with future energy use based on today’s trend [4] and will still increase, even if nations reduce their emissions to 1990 levels because of population growth and underdeveloped world increase in energy use. As the Arctic thaws, then methane, a more potent greenhouse gas than CO2, would further increase global warming [5].
Figure 1.2 Carbon dioxide in the atmosphere of the earth.
Figure 1.2 Carbon dioxide in the atmosphere of the earth.

    The Kyoto Protocol of 1996 to reduce greenhouse gas emissions became effective in 2005 as Russia became the 55th country to ratify the agreement. The goal was for the participants collectively to reduce emissions of greenhouse gases by 5.2% below the emission levels of 1990 by 2012. While the 5.2% figure was a collective one, individual countries were assigned higher or lower targets and some countries were permitted increases. For example, the United States was expected to reduce emissions by 7%. However this did not happen, as the U.S. did not ratify the treaty because the United States position was that the economic costs were too large and there were not enough provisions for developing countries, especially China, to reduce future emissions. In December 2009, Copenhagen meeting, the world is trying to set new protocols.

    If participant countries continue with emissions above the targets, then they are required to engage in emissions trading. Notable, participating countries in Europe are using different methods for carbon dioxide trading, including wind farms and planting forests in other countries.

    Increased temperatures and the effect on weather and sea level rise are the major consequences. Overall the increased temperature will have negative effects compared to the climate of 1900-2000.  By 2100 sea levels are projected to increase by 0.2 to 1 m, however 2 m is unlikely, but physically possible. With positive feedback due to less sea ice and continued increase in carbon dioxide emissions, then melting of the Greenland ice sheets would increase the sea level by over 7 m and the West Antarctic Ice Sheet would add another 5 m. The large cities on the oceans will have to be relocated or build massive infrastructures to keep out the ocean.

    1.7 Order of Magnitude Estimates

    We will use exponents to indicate large and small numbers. The exponent indicates how many times the number is multiplied by itself, or how many places the decimal point needs to be moved. Powers of ten will be very useful in order of magnitude problems, which are rough estimates.

    103 = 10*10*10 =1000

    10-3 = 1/103 = 0.001

    Note there is a discrepancy between the use of billions in the U.S. (109) and England (1012). If there is a doubt, we will use exponents or the following notation for prefixes.

Nano 10-9 Giga 109
Micro 10-6 Tera 1012
Milli 10-3 Peta 1015
Exa 1018 Kilo 103
Mega 106 Quad (Quadrillion BTU) 1015 BTU

1 Quad = 1.055 exajoules

    In terms of energy consumption, production, supply and demand and design for heating and cooling, estimates are needed and an order of magnitude estimate will suffice. By order of magnitude, we mean an answer of 1 to 2 significate digits with a power of ten.

    Example: How many seconds in a year. With a calculator it is easy

        365 days * 24 hr/day * 60 min/hr * 60 sec/hr = 31,536,000

        When you round to one significant digit, this becomes 3 * 107 seconds.

    Order of magnitude estimate. For the above multiplication round each number with a power of ten, then multiply numbers and add the powers of ten

        4 *102 * 2 *101 * 6 *101 * 6 * 101 = 4 * 2 * 6 * 6  *105

        = 288 * 105 = 3 * 102 * 105 = 3 * 107 seconds.

    1.8 Growth (Exponential)

    Our energy dilemma can be analyzed in terms of fundamental principles. It is a physical impossibility to have exponential growth of any product or exponential consumption of any physical resource in a finite system. As an example, suppose Mary started employment with $1/yr, however her salary is doubled every year, a 100% increase (Table 1.1, Fig. 1.3). Notice that after 30 years, her salary is one billion dollars. Also notice that for any year, the amount needed for the next period is equal to the total sum for all the previous periods plus one. The mathematics of exponential growth is given in Appendix 1.

 Figure 1.3 Growth with doubling time of 1 year.
Figure 1.3 Growth with doubling time of 1 year.

Table 1.1 Exponential growth with a doubling time of 1 year.

Year Salary, $ Amount = 2t Cumulative, $
0 1 20 1
1 2 21 3
2 4 22 7
3 8 23 15
4 16 24 31
5 32 25 63
2t 2t+1-1
30 1* 109 230 231-1

    Another useful idea is doubling time, T2, for exponential growth, which can be calculated by
T2 = 69/R 1.1

    where R is the % growth per unit time, generally one year. Doubling times for some different year rates are given in Table 1.2.

Table 1.2 Doubling times for different rates of growth.

Growth (%/Year) Doubling Time (Years)
1 69
2 35
3 23
4 18
5 14
6 12
7 10
8 8
9 8
10 7
15 5

    There are numerous historical examples of growth; population, 2-3%/yr; gasoline consumption, 3%/yr; world production of oil, 5-7%/yr; electrical consumption, 7%/yr. If we plotted the value per year for smaller rates of growth (Fig. 1.4), the curve would be the same as Figure 1.3, only the time scale along the bottom would be different. The United Nations projects over 9 billion people (Fig. 1.5) by 2050 [6], with the assumption that the growth rate will decrease from 1.18% in 2008 to 0.34% in 2050.

Figure 1.4 World population to 2010
Figure 1.4 World population to 2010

Figure 1.5 World population with project to 2050 under medium variant.
Figure 1.5 World population with project to 2050 under medium variant.


    This is the fundamental flaw in term of ordinary economics ($) and announcing growth in terms of percentages. How long do they want those growth rates to continue? Nobody wants to discuss how much is enough. The theme since President Reagan is that all we need is economic development and the world's problems will be solved. However the global economic crisis of 2008 and environmental problems have made some economists have second thoughts on continued growth. Now there are lots of books on the problems of fossil fuels, other resources such as minerals and water and environmental effects.

1.9 Solutions

    We do not have an energy crisis, since you will learn energy cannot be created or destroyed. We have an energy dilemma because of the finite amount of readily available fossil fuels, which are our main energy source today. The problem is twofold: population is 6.8 * 109 and growing toward 11 * 109 and developing countries want the same standard of living as developed countries. The world population is so large that we are doing an uncontrolled experiment on the earth's environment. However the developed countries were the major contributors to this uncontrolled experiment, and now consumption in China and India is adding to the problem.

    The solution depends on world, national and local policies and what policies do we implement and even individual actions. In my opinion it is obvious what needs to be done for the world; reduce consumption, zero population growth, shift to renewable energy, reduce greenhouse gas emission, reduce environmental pollution and reduce military expenditures. What do you do as an individual? I have done things in the past to save energy and have future plans. What are yours?


References, General

References, Specific

  1. Interactions, http://hyperphysics.phy-astr.gsu.edu/hbase/forces/funfor.html
  2. IPCC, 2007: Summary for Policymakers. In: Climate change 2007: The physical science basis. contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
  3. Technical Support Document for, Endangerment and cause or contribute findings for greenhouse gasses under section 202(a) of the clean air act, April 17, 2009, http://epa.gov/climatechange/endangerment/downloads/TSD_Endangerment.pdf
  4. US Climate Change Science Program, Scenarios of Greenhouse Gas Emissions and Atmospheric Concentrations; and Review of Integrated Scenario Development and Application, Final Report, July 2007,  www.climatescience.gov/Library/sap/sap2-1/finalreport/sap2-1a-final-technical-summary.pdf
  5. Sarah Simpson, “The peril below the ice,” Sci Am, Earth 3.0, Vol 18, # 2, Summer 2009, 30.
  6. United Nations, World population prospects, the 2008 revision, highlights, www.un.org/esa/population/publications/wpp2008/wpp2008_highlights.pdf


  1. What was the population of the world in 1950, 2000, this year, projected for 2050?
  2. What was the population of your country in 1950, 2000, this year, projected for 2050?
  3. List two advantages of renewable energy.
  4. List two disadvantage of renewable energy.
  5. Besides large hydro, what are the two most important renewable energy sources for your country? Do not count solar for food production.
  6. For a sustainable society in your country, what would be the two most important policy issues?
  7. What are the largest two sources in the world for carbon dioxide emissions?
  8. Besides the United States, what country consumes the most energy?
  9. What country emits the most carbon dioxide? How much per year (latest year data are available)?
  10. The size of the European Union has increased over the years. Estimate the percentage increase in GDP and energy consumption by the addition of these new blocks of countries.
  11. When is gravity considered a source for renewable energy?
  12. Global warming is primarily due to what factor?
  13. What is the predicted amount of carbon dioxide, ppm, in the atmosphere for 2050?
  14. What three nations emit the most carbon dioxide per year? What percent is that of the world total?
  15. What percent of the world total of carbon dioxide emission per year is due to combustion of coal, combustion of oil, combustion of natural gas?
  16. What is your carbon footprint? www.carbonify.com/carbon-calculator.htm or from BP, www.bp.com/iframe.do?categoryId=9023118&contentId=7045317&nicam=USCSEnergy_LabQ109&nisrc=Google&nigrp=Energy_Lab_Calculator&niadv=Carbon_Dioxide_Calculator&nipkw=co2_calculate
  17. Under the Kyoto Protocol, list 3 participating countries and what are their emission levels of carbon dioxide (latest year available) compared with their levels of 1990. Remember the target levels are below 1990 levels.
  18. The local business people want the city to grow. What rate do they want, %/year? What is that doubling time?
  19. Suppose world population grows at 0.5% per year, what is the doubling time? After that period of time, what is the projected world population?