Rethinking Renewable Mandates. Gail Tvergerg, Our Finite World. July 31, 2019.
Powering the world’s economy with wind, water and solar, and perhaps a little wood sounds like a good idea until a person looks at the details. The economy can use small amounts of wind, water and solar, but adding these types of energy in large quantities is not necessarily beneficial to the system.
While a change to renewables may, in theory, help save world ecosystems, it will also tend to make the electric grid increasingly unstable. To prevent grid failure, electrical systems will need to pay substantial subsidies to fossil fuel and nuclear electricity providers that can offer backup generation when intermittent generation is not available. Modelers have tended to overlook these difficulties. As a result, the models they provide offer an unrealistically favorable view of the benefit (energy payback) of wind and solar.
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[3] Today’s wind, water, and solar are not part of what Wrigley called the organic economy. Instead, they are utterly dependent on the fossil fuel system.
The name renewables reflects the fact that wind turbines, solar panels, and hydroelectric dams do not burn fossil fuels in their capture of energy from the environment.
Modern hydroelectric dams are constructed with concrete and steel. They are built and repaired using fossil fuels. Wind turbines and solar panels use somewhat different materials, but these too are available only thanks to the use of fossil fuels. If we have difficulty with the fossil fuel system, we will not be able to maintain and repair any of these devices or the electricity transmission system used for distributing the energy that they capture.
[4] With the 7.7 billion people in the world today, adequate energy supplies are an absolute requirement if we do not want population to fall to a very low level.
There is a myth that the world can get along without fossil fuels.
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Figure 2. World Energy Consumption by Fuel, based on data of 2019 BP Statistical Review of World Energy.
Let’s look at what it would take to ramp up the current renewables percentage from 11% to 100%. The average growth rate over the past five years of the combined group that might be considered renewable (Hydro + Biomass etc + Wind&Solar) has been 5.8%. Maintaining such a high growth rate in the future is likely to be difficult because new locations for hydroelectric dams are hard to find and because biomass supply is limited. Let’s suppose that despite these difficulties, this 5.8% growth rate can be maintained going forward.
To increase the quantity from 2018’s low level of renewable supply to the 2018 total energy supply at a 5.8% growth rate would take 39 years. If population grows between 2018 and 2057, even more energy supply would likely be required. Based on this analysis, increasing the use of renewables from a 11% base to close to a 100% level does not look like an approach that has any reasonable chance of fixing our energy problems in a timeframe shorter than “generations.”
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[6] A major drawback of wind and solar energy is its variability from hour-to-hour, day-to-day, and season-to-season. Water energy has season-to-season variability as well, with spring or wet seasons providing the most electricity.
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Why stimulus can’t fix our energy problems. Gail Tverberg. July 10, 2019.
Economists tell us that within the economy there is a lot of substitutability, and they are correct. However, there are a couple of not-so-minor details that they overlook:
- There is no substitute for energy. It is possible to harness energy from another source, or to make a particular object run more efficiently, but the laws of physics prevent us from substituting something else for energy. Energy is required whenever physical changes are made, such as when an object is moved, or a material is heated, or electricity is produced.
- Supplemental energy leverages human energy. The reason why the human population is as high as it is today is because pre-humans long ago started learning how to leverage their human energy (available from digesting food) with energy from other sources. Energy from burning biomass was first used over one million years ago. Other types of energy, such as harnessing the energy of animals and capturing wind energy with sails of boats, began to be used later.
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Many people appear to believe that stimulus programs by governments and central banks can substitute for growth in energy consumption. Others are convinced that efficiency gains can substitute for growing energy consumption. My analysis indicates that workarounds, in the aggregate, don’t keep energy prices high enough for energy producers. Oil prices are at risk, but so are coal and natural gas prices. We end up with a different energy problem than most have expected: energy prices that remain too low for producers. Such a problem can have severe consequences.
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[1] Despite all of the progress being made in reducing birth rates around the globe, the world’s population continues to grow, year after year.
Figure 1. 2019 World Population Estimates of the United Nations. Source: https://population.un.org/wpp/Download/Standard/Population/
Advanced economies in particular have been reducing birth rates for many years. But despite these lower birth rates, world population continues to rise because of the offsetting impact of increasing life expectancy. The UN estimates that in 2018, world population grew by 1.1%.
[2] This growing world population leads to a growing use of natural resources of every kind.
There are three reasons we might expect growing use of material resources:
(a) The growing world population in Figure 1 needs food, clothing, homes, schools, roads and other goods and services. All of these needs lead to the use of more resources of many different types.
(b) The world economy needs to work around the problems of an increasingly resource-constrained world. Deeper wells and more desalination are required to handle the water needs of a rising population. More intensive agriculture (with more irrigation, fertilization, and pest control) is needed to harvest more food from essentially the same number of arable acres. Metal ores are increasingly depleted, requiring more soil to be moved to extract the ore needed to maintain the use of metals and other minerals. All of these workarounds to accommodate a higher population relative to base resources are likely to add to the economy’s material resource requirements.
(c) Energy products themselves are also subject to limits. Greater energy use is required to extract, process, and transport energy products, leading to higher costs and lower net available quantities.
Somewhat offsetting these rising resource requirements is the inventiveness of humans and the resulting gradual improvements in technology over time.
What does actual resource use look like? UN data summarized by MaterialFlows.net shows that extraction of world material resources does indeed increase most years.
Figure 2. World total extraction of physical materials used by the world economy, calculated using weight in metric tons. Chart is by MaterialFlows.net. Amounts shown are based on the Global Material Flows Database of the UN International Resource Panel. Non-metallic minerals include many types of materials including sand, gravel and stone, as well as minerals such as salt, gypsum and lithium.
[3] The years during which the quantities of material resources cease to grow correspond almost precisely to recessionary years.
[4] World energy consumption (Figure 4) follows a very similar pattern to world resource extraction (Figure 2).
Figure 4. World Energy Consumption by fuel through 2018, based on 2019 BP Statistical Review of World Energy. Quantities are measured in energy equivalence. “Other Renew” includes a number of kinds of renewables, including wind, solar, geothermal, and sawdust burned to provide electricity. Biofuels such as ethanol are included in “Oil.”
Note that the flat periods are almost identical to the flat periods in the extraction of material resources in Figure 2. This is what we would expect, if it takes material resources to make goods and services, and the laws of physics require that energy consumption be used to enable the physical transformations required for these goods and services.
[5] The world economy seems to need an annual growth in world energy consumption of at least 2% per year, to stay away from recession.
There are really two parts to projecting how much energy consumption is needed:
- How much growth in energy consumption is required to keep up with growing population?
- How much growth in energy consumption is required to keep up with the other needs of a growing economy?
To estimate how much growth in energy supply is needed to keep up with the other needs of a growing economy, we can look at per capita historical relationships:
[6] In the years subsequent to 2011, growth in world energy consumption has fallen behind the 2% per year growth rate required to avoid recession.
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[7] The growth rates of oil, coal and nuclear have all slowed to below 2% per year since 2011. While the consumption of natural gas, hydroelectric and other renewables is still growing faster than 2% per year, their surplus growth is less than the deficit of oil, coal and nuclear.
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[8] The economy needs to produce its own “demand” for energy products, in order to keep prices high enough for producers. When energy consumption growth is below 2% per year, the danger is that energy prices will fall below the level needed by energy producers.
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Perhaps the best way of summing up how my model of the world economy differs from other ones is to compare it to other popular models.
The Peak Oil model says that our energy problem will be an oil supply problem. Some people believe that oil demand will rise endlessly, allowing prices to rise in a pattern following the ever-rising cost of extraction. In the view of Peak Oilers, a particular point of interest is the date when the supply of oil “peaks” and starts to decline. In the view of many, the price of oil will start to skyrocket at that point because of inadequate supply.
To their credit, Peak Oilers did understand that there was an energy bottleneck ahead, but they didn’t understand how it would work. While oil supply is an important issue, and in fact, the first issue that starts affecting the economy, total energy supply is an even more important issue. The turning point that is important is when energy consumption stops growing rapidly enough–that is, greater than the 2% per year needed to support adequate economic growth.
The growth in oil consumption first fell below the 2% level in 2005, which is the year that some observers have claimed that “conventional” (that is, free flowing, low-cost) oil production peaked. If we look at all types of energy consumption combined, growth fell below the critical 2% level in 2012. Both of these issues have made the world economy more vulnerable to recession. We experienced a recession based on prices that were too high for consumers in 2008-2009. It appears that the next bottleneck may be caused by energy prices that are too low for producers.
Recessions that are based on prices that are too low for the producer are the more severe type. For one thing, such recessions cannot be fixed by a simple interest rate fix. For another, the timing is unpredictable because a problem with low prices for the producer can linger for quite a few years before it actually leads to a major collapse. In fact, individual countries affected by low energy prices, such as Venezuela, can collapse before the overall system collapses.
While the Peak Oil model got some things right and some things wrong, the models used by most conventional economists, including those included in the various IPCC reports, are far more deficient. They assume that energy resources that seem to be in the ground can actually be extracted. They see no limitations caused by prices that are too high for consumers or too low for producers. They do not realize that affordable energy prices can actually fall over time, as the economy weakens.
Conventional economists assume that it is possible for politicians to direct the economy along lines that they prefer, even if doing so contradicts the laws of physics. In particular, they assume that the economy can be made to operate with much less energy consumption than is used today. They assume that we collectively can decide to move away from coal consumption, without having another fuel available that can adequately replace coal in quantity and uses.
History shows that the collapse of economies is very common. Collectively, we have closed our eyes to this possibility ever happening to the world economy in the modern era. If the issue with collapsing demand causing ever-lower energy prices is as severe as my analysis indicates, perhaps we should be examining this scenario more closely.
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