Coal: why it can’t easily substitute for oil

In a major 2009, 737 page landmark study of our energy predicament, the National Academy of Sciences proposes  that the only possible near-term solution to a substitute transportation fuel to replace gasoline is liquified coal.   Liquified coal is the only possible substitute for oil since biofuels are both ecologically destructive, too small in amount to make a dent in our need of fuel, and probably use more fossil fuel energy to create than what’s returned in the final product.

1) But we’re at Peak Coal now:

  1. R. Heinberg. The End of Cheap Coal. Nature 468. 18 Nov 2010.
  2. T. Patzek. A global coal production forecast with multi-Hubbert cycle analysis.  Energy
  3.             35 (2010) 3109-3122
  4. R. Heinberg. Blackout. Coal, Climate and the Last Energy Crisis. 2009
  5. A. Friedemann. Peak Coal is already here or likely by 2020 — if true — IPCC 100 year projections too high? 2013.
  6. New York Academy of Sciences. Full cost accounting for the life cycle of coal. 2011 pp 73-98

2) Coal doesn’t contain as much energy as oil. It’s fifty to two hundred percent heavier than oil per unit of energy generated, which makes it far more energy-intensive to transport.  1,000,000 Btus = 90 pounds of coal = 8 gallons of gasoline. 1 trillion btus: = train 4 1/4 miles long = 8 million gallons of gas

3) According to David Goodstein, professor of Physics at Caltech and author of Out of Gas: the End of the Age of Oil: “We use about twice as much energy from oil as we do from coal, so if you wanted to mine enough coal to replace the missing oil, you’d have to mine it at a much higher rate, not only to replace the oil, but also because the conversion process to oil is extremely inefficient. You’d have to mine it at levels at least five times beyond those we mine now—a coal-mining industry on an absolutely unimaginable scale.”

4) Turning even more heavily to coal will accelerate global warming and sudden climate change.

5) Coal is lumpy — you can’t pour it into your gas tank.

6) Liquefying coal takes half the energy contained in the coal.

7) Coal liquefaction requires huge plants that are as expensive to build as oil refineries (no new refineries have been built in the United States for thirty years). Where will the capital for this come from?  It also requires enormous volumes of water, which is short in many regions of the country.

The National Academy of Sciences recommends liquified coal and biomass plants be built immediately to cope with declining amounts of fossil fuels in a 737 page report (NAS 2009). Yet even with a 20% average annual growth rate to 2035, when 280 plants would be in place, only 2.5 million bbl/d of gasoline equivalent would be produced (we burn 21 million bbl/d). This would consume about 300 million dry tons of biomass and about 250 million tons of coal per year.

Since we have no idea how to store carbon (CCS), it is just ghastly that in the end that we will probably go ahead anyhow because it is just a temporary stop-gap measure, when clearly there is no other technology that will ever step in to replace fossil fuels.

8) We barely have the rail infrastructure to get coal to electrical generation plants. Currently 40% of train cars carry coal. Even if the train network were increased, there is a limit to how many trains can physically be brought to a coal mine.

9) When coal is burned in coal-fired power plants, coal emits more radiation than nuclear power plants. The acids released are ruining farmland and forests. Coal also emits arsenic, sulfur, and mercury, which is why you can only eat fish a few days a month across the lower 48 states.

10) There is a notion that we have hundreds of years of coal to burn, but if we turn mainly to coal provide liquid fuel (it already accounts for half of our electricity generation), then we have about fifty years of coal left (a lot less actually if you read the peak coal articles in #1 above), and even less than that if our use of it and our population continues to grow exponentially.

11) We’ve already mined the best and most accessible coal. The deeper we dig, the greater the minimum energy requirements. Since the best quality and most accessible coal were mined first, more and more energy is required to mine and refine increasingly poor quality resources.

12) Mining coal is tremendously destructive to the environment.

13) Liquefied coal (CTL) is a water guzzler, requiring 3 barrels of water for every barrel of coal.

14) We don’t know how to sequester carbon dioxide with the certainty that it won’t escape back into the environment. The space to sequester carbon dioxide is limited, and if the plan is to inject it into geologically stable oil wells, the cost of running pipelines from the power plant might be prohibitively expensive both energy and dollar-wise.

15) CTL might make people foolish enough to think we can continue on the way we have been, and not make changes in our lives.

16) Clean coal is a mirage.Here’s an October 2013 article about where clean coal stands today:

My summary of Joe Romm’s Carbon Capture And Storage: One Step Forward, One Step Back

It’s a public relations mirage. The reality is that the scale of technology required to capture and bury the CO2 from all the coal power plants in the US would be roughly equivalent to the scale of the entire oil and gas industry in North America.

Imagine the cost and the investment required to produce that size of infrastructure. Not to actually produce more energy, but simply to mitigate some of the environmental impacts from current energy production.

Obviously that will add to the cost of electricity. It only begins to make sense if we assume that coal is going to be cheap from now until kingdom come, which is a false assumption. China’s coal consumption has been rising at about 8% per year for the past few years. China is starting import coal. China would like to import coal from the United States. What this means is that coal is going to be less affordable globally as time goes on and that means that extra cost from carbon capture and storage simply cannot be borne because of the high cost of coal. The reality is that as coal costs increase, almost any other source of electricity–even solar–will be cheaper by comparison than clean coal. Clean coal is a technology without a future (Heinberg).

17) It’s hard to finely control the burning of coal, unlike oil, and coal-mining machinery and transportation runs on oil-ased fuels, not coal.

Heinberg, Richard.  6 Jan 2012. Heinberg, Kunstler, Foss, Orlov & Chomsky on A Public Affair WORT FM (89.9) in Madison, WI.

South African Sasol produces 165,000 barrels per day of liquified coal for transportation, and also converts natural gas into synthesis gas which is converted into diesel and gasoline by the Fischer-Tropsch process.


Coal is what enabled the “Industrial” Revolution (Source: adapted from Wrigley, E.A. (2010), Energy and the English industrial revolution, Cambridge University Press.)



The blue part of top bar is a fantasy, hydrogen is not a solution or energy resource, but otherwise, this is a good picture of the evolution from coal to oil

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