Tuesday, February 24, 2015

Getting Real About Energy in Cubic Miles of Oil

Today, with plummeting oil prices and news reports of US oil production poised to exceed that of Saudi Arabia’s, there is a perception on the street that there is no energy crisis. Yet just a few years ago, we were all talking about one. Have things changed so dramatically so fast? We paid considerable attention to the energy crisis following the oil crunch in the 1970s, but then oil prices plunged, and public attention waned, and with it the efforts at conservation and improving fuel efficiency of vehicles. However, the underlying situation and the challenges facing us had not changed, and nor have they changed this time. A crisis is a terrible thing to waste, and we seem to be doing it all over again.  I recently spoke about it with Artist Michael Killen.


Meeting the global demand for energy remains a daunting task, and the energy sources we choose to employ will have a profound effect on the lives of billions of people around the world. People have to be involved in making the choice, or the choice will be made for them. For a sustained, informed public debate on this subject, it is necessary to have a common language that is readily understood by the specialist and the non-specialist. A Cubic Mile of Oil (Oxford University Press, 2010) provides a language to talk plainly yet intelligently about energy, and how to assess our future needs and evaluate our progress.

Energy use is essential to our well-being—it is our sustenance. We use it in all aspects of living: growing food, manufacturing, transportation, communication, lighting, heating and cooling, earning our livelihoods, for entertainment, and more. All these tasks require energy, and we derive it from many different sources such as oil, coal, natural gas, hydro power, nuclear fission, and wind and solar power. Unfortunately, energy from these sources is expressed in different and often unfamiliar units, which makes it hard to assess their relative contributions. We use kilowatt hours for electricity, gallons or barrels for oil, cubic feet for gas, British thermal units (btus) or tons for coal, and so on—it’s a veritable tower of Babel! 

Further, each of these units represents a relatively small amount of energy, and in order to express energy use at a global or national scale, we have to use mind-numbing multipliers like millions, billions, trillions, and even quadrillions. To overcome this problem, my colleague Hew Crane came up with the idea of expressing energy units from all the different sources in one large volumetric measure that is commensurate with the scale of global energy challenge and one for which we can form a mental image. The approximately 90 million barrels of oil the world currently consumes daily adds up to a little over a cubic mile of oil in a year, or one CMO. A CMO thus becomes a very convenient unit to express annual global energy production and consumption. Imagine a pool a mile long, a mile wide, and mile deep, and you have a cubic mile. That’s more than a thousand times the volume of a typical sports arena.

In 2013, the global consumption of oil was 1.1 cubic mile. The world consumed an additional CMO of energy from coal, about three-quarters of one CMO from natural gas, and roughly a quarter of one CMO each from hydrothermal, nuclear power, and wood burning, yielding a grand total of 3.5 CMO. All combined, solar, wind, and biofuels produced less than a tenth of a CMO in 2013. How much will we need in the future? That depends on how seriously we take the UN millennium goals for human development. Between 1981 and 2005, China lifted over 600 million people from poverty, reducing the poverty rate from 85% to 16%. Concomitantly, the infant mortality rate declined from 2100 deaths per day to 770 per day. This achievement was made possible by quadrupling energy consumption. 

Global statistics on poverty are stark: 1.4 billion people subsist below the poverty level, defined by the World Bank as living on $1.25/day; infant mortality is 17,000 children a day; 2.4 billion people rely on wood, charcoal, or dung as their primary source of energy, and women and young girls spend more than 6 hours each day collecting fuel and water and completing other chores that deprive them of opportunities for advancement through education and entrepreneurship. Roughly 1.5 billion people have no access to electricity. Even after implementing measures to conserve and markedly improving energy efficiency, it is estimated that annual global energy consumption will have to increase by several CMO/yr to remove the scourge of poverty and to allow all people to lead healthy, productive lives. 

The challenge of supplying energy to the world’s population is really overwhelming. Even at a modest growth rate of 2% per year (i.e., a doubling every 36 years), the world’s energy demand by 2050 will be over 7 CMO per year. As we seek solutions to the energy crisis, we have to ensure they scale to the CMO per year level¾if not, we will just be nibbling at the edges. When you consider what it takes to develop an infrastructure capable of producing even one CMO of energy, it becomes evident there are no easy solutions, and it will take an enormous effort sustained over many decades to effect meaningful change. 

The slide below illustrates how many power plants it will take to develop capacity for producing 1 CMO/yr.  For each resource, it shows the total number of plants and the rate at which they must be built in order that in fifty years we will have enough of them to produce 1 CMO/yr. Because such analyses are highly dependent on the size and availability factors, I have also included those details. The numbers are truly sobering.

In case you are wondering about the impact of continued use of fossil fuels on climate change, please read my post from June 2012, where I discuss the need for a differentiated approach and a focus on things that matter. And oh, did I mention it is also time to seriously look at nuclear again. Speaking of nuclear power, I was recently informed that this unit was also used by President Jimmy Carter, although—being a navy man—his preference was cubic nautical miles!


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  2. The devices that are used to capture the sun and wind’s energy are an extension of the fossil fuel supply system. There is a massive infrastructure of mining, processing, manufacturing, fabricating, installation, transportation and the associated environmental assaults. There would be no sun or wind capturing devices with out this infrastructure. This infrastructure is not green, sustainable, or renewable. The making of these devices inadvertently but directly supports fracking, tar sands and deep ocean drilling because of the need for this infrastructure.

    In addition, the Energy Returned on Energy Invested (ERoEI) is very marginal for all solar devices. It takes years if ever to repay the energy it took to make, install, and maintenance these devices.
    And even if you could get around the environmental degradation, the low ERoEI and could amass enough extra energy to reproduce the capturing devices and their equipment, then how about the rest of the STUFF of high tech, high energy society?
    We don't agree on nuclear. I don't believe humanity is mature enough to handle nuclear.

    1. John, I suggest you read up on the Molten Salt Reactor: It can't blow up, melt down, make bombs and is walk away safe and it should cheap to build on an assembly line. www.energyfromthorium.com

  3. Perhaps you would find this interesting. It would be elegant if wind and solar energy capturing devices could actually maintain a modicum of the wonderfully rich lifestyles many of us live. I believe this is a false dream and that BAU (business as usual) is not sustainable or “green” nor really desirable for the future of the earth or even our species.

    I have researched the energy requirements and the CO2 emissions for just the rebar and concrete used for the base of a 2.5 megawatt wind energy capturing device (wind turbine). Notice also all the equipment needed throughout the process of making and installing; these in themselves have an input of energy the materials. There are charts and pictures. It is sobering.
    See charts and data at: http://sunweber.blogspot.com/2014/11/prove-this-wrong.html

  4. John,
    Thank you for your interest, and yes I totally agree that the energy capture devices also require inputs or investments of fossil energy. Also implementation on a massive scale will have its own environmental impact—not all of which will be anticipated in advance.

    However, I want to make sure that readers realize that despite some very large energy inputs, the returns on these investments are positive; in other words over the life of the device, the energy produced by it exceeds all the energy inputs. For a wind turbine of the kind you illustrate, the energy return over the lifetime is about 20-25 times what was put in, and the payback period is a just a few years. A recent research paper by Mathews and Tan that analyzes the material and land requirements for an all wind, water, and solar scenario. The requirements for steel and concrete are huge, but within the global supply chain.
    "A 10 Trillion Watt ‘Big Push’ to Decarbonize the World’s Electric Power," by J. Mathews and H. Tan, Journal of Sustainable Energy Engineering Vol 2, p. 87, 2015.
    DOI: 10.7569/JSEE.2014.629505 (subscription required)

  5. Ripu, apologies, but for my clarity, can you say, is your conclusion that we should build out some mix of the CMO equivalents shown above, either to meet the increase in demand to 7 CMO by 2050, or, not stated above, to cover over the decline in oil production that many even optimistic folks think will happen by 2050? Your very slide leaves me with the opposite (intuitive) conclusion, at least for purely environmental reasons. I have trouble envisioning a mix of say, xx new 3 gorges dams, xxx more nuclear power plants, XX number of solar parks, etc. So I was just wondering, are you advocating here for such a infrastructure build out? Thanks for reply. Shawn B.

  6. Shawn,
    Thank you for engaging in this conversation. You are right; I did not advocate any specific approach to meeting the energy demand. The point in this post first and foremost to make clear the need for additional energy. Not providing sufficient energy has dire consequences, and if keep rejecting every solution, we are in a way saying it is OK that poverty claims 17,000 infants a day!

    As we elaborate in the book, all of our current energy sources have environmental consequences, particularly when they are scaled to a CMO/yr level. There are tradeoffs to be made, and since different people value things differently, the public has to be engaged in an informed debate to make its choices. Given the enormity of the challenge, it is not an either/or situation; AND is the operative conjunction.

    Personally, I would like to see much wider deployment of nuclear technology. It is frustrating to me that there is so much fear and misinformation associated with nuclear power. And, yet, it is one of the safest and has the best record. we devote a very large section on nuclear power in the book pointing out misinformation-based fears, identifying the substantive challenges, and how they are being addressed in Gen IV and other new designs of nuclear reactors.


  7. I'm not really clear with how much is needed to replace 1 CMO. It looks like one option is sufficient to replace 1 CMO. But I get that it takes 27 years for them all to reach 1 CMO.
    1 CMO is 44 540 TWh
    4 Tree Gore per year is 315 Two
    52 Nuclear plant per year is 369 TWh
    156 Solar plant per year is 307 TWh
    62 400 Windmills per year is 316 TWh
    91 250 000 Solar roof per year is 336 TWh
    That is a total of 1 643 TWh for year one, or 0,037 CMO.
    In year two we dubbled the produktion and have 3 286 TWh or 0,074 CMO
    In year 28 we have 46 010 TWh or 1,033 CMO
    And in year 50 we have 82 160 TWh or 1,845 CMO, there is no decommission of plants in the calculation.

    1. Bengt,
      Evidently I did not do a good job explaining that slide, and I apologize for creating confusion.

      The slide is meant to illustrate how many power plants it will take to develop capacity for producing 1 CMO/yr. The answer for each case is discussed in three lines. The first line gives the total number of plants of each kind that are required to produce 1 CMO/yr. Second line gives the the rate at which they must be built so that by year 50 you have enough of them (assuming they are all still working). The third line spells out the specifics of the power plant being considered (power rating and availability).

      One other thing. Although in primary energy equivalence 1 CMO = 44,450 TWh, for power output of electricity, I use 1 CMO is equivalent to 15,300 TWh. That is because the effective heat rate of coal or natural gas power plants is about 10,000 Btu/kWh and not 3,414 Btu/kWh. Thus, for each kWh of electric power output the hydro- or PV plant has displaced 10,000 Btu of fossil energy.

    2. Thank you that was helpful, now I know. But the real problem is that we need oil for the transport-sector. That would be interesting to have one CMO from biodiesel and the use of land area.

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