Peak Coal

Thursday, May 19, 2011

Predictions about peak coal in the 1800s were wrong. But even if peak oil is true, natural gas, cleaner than coal and oil, can take its spot, followed by renewables as their technology gets cheap enough.

In 1865 a young economist named W. S. Jevons published a book titled The Coal Question in which he argued that Britain’s “present lavish use of cheap coal” could not continue as coal would soon run out and continued prosperity was therefore “physically impossible. We have to make the momentous choice between brief greatness and longer continued mediocrity.” Gladstone, as Chancellor, found Jevons’ “grave and ... urgent facts” so persuasive that he proposed to Parliament, with the support of John Stuart Mill, to retire the national debt while the good times lasted.

In fact, coal output rose and the price fell for many decades. Jevons’ gloomy warning that “it is useless to think of substituting any other kind of fuel for coal” was hilariously timed, six years after the first oil wells were drilled in Pennsylvania.

“Experts” regularly rush to predict the exhaustion of fossil fuels. “Already the output of [natural] gas has begun to wane. Production of oil cannot long maintain its present rate,” a US presidential commission said in 1922. “We could use up all the proven reserves of oil in the entire world by the end of the next decade,” Jimmy Carter said in 1976.

The world will use about 450 exajoules (billion billion joules) of fossil fuel energy this year and has so far used less than 20,000 exajoules since the Industrial Revolution began. Total oil, gas and coal resources in the Earth’s crust are estimated at more than 570,000 exajoules.

Shale gas was thought to be as inaccessible as clathrates, and when it began to be exploited in the 1990s it looked as if it would still come in at the top of the price range. Now technological improvements have brought the price down so far that it undercuts conventional gas.

Shale gas is good news for America and China (which probably has even more of it than America), consumers (cheap fuel means higher standards of living) and farmers (fertiliser is made from gas).

Wrong about Running Out, Matt Ridley, May 7, 2011, http://www.rationaloptimist.com/blog/wrong-about-running-out.

The dominant fuel in the world fuel mix has gradually shifted from wood to coal to oil over the past 150 years, with gas the latest fuel to grow rapidly. At this rate gas may overtake oil as the dominant fuel by 2020 or 2030. The consequence of this succession is that the carbon-hydrogen ratio in the world fuel mix has been falling steadily, because the ratio of carbon to hydrogen atoms is about 10-to-1 in wood, 2-to-1 in coal, 1-to-2 in oil and 1-to-4 in gas. On its current trajectory, the average ratio would reach 90% hydrogen in 2060, having been 90% carbon in 1850. Jesse Ausubel of Rockefeller University describes this phenomenon as follows:

When my colleagues Cesare Marchetti, Nebojsa Nakicenovic, Arnulf Grubler and I discovered decarbonisation in the 1980s, we were pleasantly surprised. When we first spoke of decarbonisation, few believed and many ridiculed the word. Everyone ‘knew‘ the opposite to be true. Now prime ministers and presidents speak of decarbonisation. Neither Queen Victoria nor Abraham Lincoln decreed a policy of decarbonisation. Yet, the energy system pursued it. Human societies pursued decarbonisation for 170+ years before anyone noticed.

Consequently, although increased energy use means that carbon dioxide emissions are rising all the time, the world is nonetheless slowly decarbonising. A sudden and forced acceleration of this decarbonisation is what environmentalists and many politicians are demanding in the name of climate change policy. The argument is that the cost of waiting for decarbonisation to happen of its own accord is higher than the cost of replacing existing fuels with low-carbon alternatives.

However, few of the low-carbon alternatives are ready to take up the challenge on a scale that can make a difference. Nuclear is too slow and costly to build; wind cannot provide sufficient volume of power or reliability; solar is too expensive; biofuel comes at the expense of hunger and high carbon dioxide emissions. All except nuclear (and to a lesser extent solar) require unacceptably vast land grabs. Diverting 5% of the entire world grain crop into the US ethanol program in 2011 will displace just 0.6% of world oil use ; getting 10% of Denmark‘s electricity from wind has saved no net carbon emissions (because of the need for inefficient back-up generation).

The world would do well to heed the advice of Voltaire and not make the best the enemy of the good. Rapid decarbonisation using renewables is not just expensive and environmentally damaging, it is impossible. However, switching as much power generation from coal to gas as possible, and as much transport fuel from oil to gas as possible, would produce rapid and dramatic reductions in carbon dioxide emissions.

The Shale Gas Shock, Matt Ridley, 2011, http://thegwpf.org/images/stories/gwpf-reports/Shale-Gas4May_11.pdf.