y are parallel. Energy in some sense powers the economy, in a way similar to how food powers humans.
On Slide 5, I am pointing out that changes in the red line, denoting energy consumption growth, tend to come before the corresponding changes in the blue line. This is one way of confirming that energy consumption causes GDP growth, rather than vice versa.
In recent years, countries have found ways of creating GDP growth, without adding true value. This may explain why GDP growth is higher than Energy growth since 2013 on Slide 5. As an example of GDP growth with overstated value, a large share of young people are now being encouraged to purchase advanced education, at considerable cost. This would make sense, if there were suitable high-paying jobs for all of those graduating. It is questionable whether this is the case.
Of course, the issue is not only energy consumption, just as our health is influenced by more than simply what food we eat.
At one time, the emphasis in physics was on systems that are “closed” from an energy point of view. Such systems never grow; they simply decline toward “heat death.”
The real world is made up of many structures that grow and change over time. This growth and ability to change is possible because the energy system we live in is thermodynamically “open,” thanks to flows of energy from the sun, and thanks to fossil fuel energy, which represents stored solar energy from long ago.
The answers to the questions on Slide 8 are easy to guess.
The economy adds new businesses, as citizens see new needs and set up companies to meet those needs. Customers make choices regarding which goods and services to buy, based on their income (primarily wages) and the prices of available goods and services. Governments gradually add new laws, including changes to the way taxes are assessed. The system gradually grows and changes, as the population grows, and as the quantity of goods and services created to meet the needs of that population increases.
One thing to note is that the goods and services produced by the system will eventually be divided among the various players in the system. If one group gets more (say, those receiving interest income), then other groups will necessarily receive less.
Another important point to note is that as new products are added, old ones disappear. For example, once cars came into use, we lost the ability to go back to horses and buggies. There are no longer enough horses; there are no longer facilities to “park” the horses in downtown areas, while at work or shopping; and there are no longer services to clean up after the mess that the horses make.
Without being able to go backward, the system is quite brittle. It would appear that under sufficiently adverse conditions, the entire system could collapse. In fact, we know that many ancient civilizations did collapse, when conditions weren’t right.
The strange interconnections of a networked system make the world economy behave in a different way than we might initially expect. Later in this presentation (in Part 2 of the write-up), I will show some examples of inadequate energy supplies leading to very different results than high prices.
The model of The Limits to Growth looked at how long resources might last, before the growth of the world economy came to a halt from a variety of problems, including a lack of easy-to-extract resources. In some ways, the model was quite simple. For example, the model did not include a financial system or debt. In the single most likely scenario, the base run, the world economy hit limits about now, in the 2015 to 2025 time period. The authors have said that, once limits are hit, the forecast on the right-hand side of the chart cannot be relied upon; the model is too simple to forecast how the down slope might actually occur.
The pattern of world energy consumption seems to be one of rapid growth, especially in the period since World War II.
Energy consumption growth is particularly high in the period covered by the red box. In other words, energy consumption growth is particularly high fr