“Taking temporarily high rates of annual exponential growth as indicators of future long-term developments is a fundamental mistake.”

Vaclav Smil, writing in Growth: From Microorganisms to Megacities:

Taking temporarily high rates of annual exponential growth as indicators of future long-term developments is a fundamental mistake — but also an enduring habit that is especially favored by uncritical promoters of new devices, designs, or practices: they take early-stage growth rates, often impressively exponential, and use them to forecast an imminent dominance of emerging phenomena.

Many recent examples can illustrate this error, and I have chosen the capacity growth of Vestas wind turbines, machines leading the shift toward the de-carbonization of global electricity generation. This Danish maker began its sales with a 55 kW machine in 1981; by 1989 it had a turbine capable of 225 kW; a 600 kW machine was introduced in 1995; and a 2 MW unit followed in 1999. The best-fit curve for this rapid growth trajectory of the last two decades of the 20th century (five-parameter logistic fit with R2 of 0.978) would have predicted designs with capacity of nearly 10 MW in 2005 and in excess of 100 MW by 2015. But in 2018 the largest Vestas unit available for onshore installations was 4.2 MW and the largest unit suitable for offshore wind farms was 8 MW that could be upgraded to 9 MW (Vestas 2017a), and it is most unlikely that a 100 MW machine will be ever built.

This example of a sobering contrast between early rapid advances of a technical innovation followed by inevitable formation of sigmoid curves should be recalled whenever you see news reports about all cars becoming electric by 2025 or new batteries having impressively higher energy densities by 2030.

But the final, inescapable power of this reality may seem inapplicable in those cases where exponential growth has been underway for an extended period of time and when it keeps setting new record levels. More than a few normally rational people have been able to convince themselves — by repeating the mantra “this time it is different” — that performances will keep on multiplying for a long time to come.

October 28, 2020
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Energy and Civilization: A History

Notes from Energy and Civilization: A History by Vaclav Smil:

* From a fundamental biophysical perspective, both prehistoric human evolution and the course of history can be seen as the quest for controlling greater stores and flows of more concentrated and more versatile forms of energy and converting them, in more affordable ways at lower costs and with higher efficiencies, into heat, light, and motion.

* Every form of energy can be turned into heat, or thermal energy. No energy is ever lost in any of these conversions. Conservation of energy, the first law of thermodynamics, is one of the most fundamental universal realities. But as we move along conversion chains, the potential for useful work steadily diminishes. This inexorable reality defines the second law of thermodynamics, and entropy is the measure associated with this loss of useful energy. While the energy content of the universe is constant, conversions of energies increase its entropy (decrease its utility).

* A great deal of traditional farming required heavy work, but such spells were often followed by extended periods of less demanding activities or seasonal rest, an existential pattern quite different from the nearly constant high mobility of foraging. The shift from foraging to farming left a clear physical record in our bones. Examination of skeletal remains from nearly 2,000 individuals in Europe whose lives spanned 33,000 years, from the Upper Paleolithic to the twentieth century, revealed a decrease in the bending strength of leg bones as the population shifted to an increasingly sedentary lifestyle. This process was complete by about two millennia ago, and there has been no further decline in leg bone strength since then, even as food production has become more mechanized, an observation confirming that the shift from foraging to farming, from mobility to sedentism, was a truly epochal divide in human evolution.

* The organic fertilizer with the highest nitrogen content (around 15% for the best deposits) is guano, droppings of seabirds preserved in the dry climate of islands along the Peruvian coast.

* Until the early 1980s there were no private cars in China, and until the late 1990s most commuters rode bicycles even in the country’s large cities.

* Electricity is the most convenient, most versatile, and, at the point of its use, the cleanest form of modern energy.

* Infant mortality is an excellent proxy for conditions ranging from disposable income and quality of housing to the adequacy of nutrition, level of education, and a state’s investment in health care: very few babies die in countries where families live in good housing and where well-educated parents (themselves well nourished) feed them properly and have access to medical care. And, naturally, life expectancy quantifies the long-term effects of these critical factors.

* That fossil fuel resources are finite does not imply any fixed dates for the physical exhaustion of coals or hydrocarbons, nor does it mean the early onset of unbearably rising real costs of recovering these resources and hence the necessity of a rapid transition to a post-fossil fuel era. […] Consequently, it is not worries about an early exhaustion of fossil fuels – most prominently expressed by the advocates of imminent peak oil – but rather the impact on the habitability of the biosphere (above all through global climate change) that is the most important near-and long-term concern resulting from the world’s dependence on coals and hydrocarbons.

January 10, 2020
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Oil: A Beginner’s Guide

Notes from Oil: A Beginner’s Guide by Vaclav Smil:

* In 2016 motor and aviation gasoline accounted for a third of global refinery throughput. The US share of global gasoline consumption was about 41% of the total, or more than 1,200kg/capita: the country now consumes more gasoline than the combined total for the EU, Japan, China and India.

* Nearly two-thirds of the world’s refined products are now used in transportation (roughly 2.5Gt in 2005) and in the US that share is now more than 75%. Transportation’s dependence on liquid fuels is even higher: in 2015 about 93% of all energy used by road vehicles, trains, ships and planes came from crude oil.

* In 1900 American farmers needed an average of about three minutes’ labor to produce 1kg of wheat, but by the year 2000 the time was down to just two seconds and the best producers now do it in one second.

* The second most voluminous non-fuel use of a refined petroleum product is asphalt.

* Only about 20% of diamonds are sold to the jewellery trade; most of the rest go into drilling for hydrocarbons and metallic ores.

* Record US well depths reached with rotary rigs increased from 300m in 1895 to more than 1.5km by 1916; the 3km mark was reached in 1930, the deepest pre-WWII well was 4.5km (in 1938) and the 6km mark was surpassed in 1950.

* The average depth of new US exploratory oil wells increased from about 1,460m during the 1950s to nearly 2,300m during the first decade of the twenty-first century.

* Fracking fluid is about 90% water. Most of the rest is sand, and additives (hundreds of substances have been tried) usually make up less than 0.5% of the volume but they contain a mix of chemicals (acids, corrosion inhibitors, gelling agents, surfactants, biocides) that should never be allowed to contaminate drinking water. Usually this is not a problem as fracking takes place far below the aquifers, and steel and cement in properly finished wells should prevent any contamination closer to the surface.

* Moving Alaskan oil 3,800km by tanker from Valdez to Long Beach in California requires energy equivalent to only about 0.5% of the transported fuel. And a 300,000dwt supertanker needs an equivalent of only about 1% of the fuel it carries in order to travel more than 15,000km from Ra’s Tanūra, the world’s largest loading oil terminal on the Saudi coast of the Persian Gulf, to the US East Coast.

* By far the largest oil storage is the US Strategic Petroleum Reserve that began to fill in 1977 with imported Saudi oil. Crude oil is stored deep underground in four massive salt caverns along the Texas and Louisiana Gulf Coast. The maximum capacity is 713.5Mb and the reserves stood at 685Mb in June 2017, representing about 10% of US annual oil consumption.

* The chances of ending the fossil fuel era in a matter of two or three decades appear quite unrealistic: in 2017 the world derived about 85% of its primary commercial energy from the combustion of fossil carbon.

December 30, 2019
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