Why are we in the present situation?

Why are we in the present situation, using 80% of non-renewables? In this lesson, we will take a closer look at our current energy system, our energy usage, and the emissions that come from it.

Let’s start by having a look at the history of the utilization of fossil fuels. In that way we can find an explanation for why we are so dependent on fossil fuels.

1. Fossil energy has been a fundamental driver during the last 150 years

• Until the 19th century, humans relied on very basic forms of energy: food, fodder and burning of biomass.
• A more systematic exploration of fossil fuels started along with the industrial revolution, first with coal, followed by oil and gas (see chart below).
• The development around the steam engine – a heat engine that performs mechanical work – was of very big importance for industrialization.
• Fossil energy has been a fundamental driver of the development progress during the last 150 years.

Global fossil fuel consumption. Source: OurWorldInData.org/fossil-fuels, CC BY. Click to expand

2. High energy density of fossil fuels freed up land and labor for other uses

• The energy transition that took part over 100 years ago from wood to coal (and later to oil and gas) meant changing to fossil fuels with higher densities than biomasses (see chart below).
• This was very beneficial for energy infrastructure and released land areas and labor forces to be used in other ways.
• Countries with access to affordable resources (fossil fuels) had an advantage in the industrialization process.

Energy density for some fuels (GJ/t). Anthracite and hard coal are fossil fuels, while firewood and energy willow are examples of biomass. Source: Statistics Finland, 2021. Click to expand

Note: Comparing energy content per volume the difference between coal and biomass is even bigger!

3. After World War II: rapid increase in energy demand – and also in population growth

• A more rapid increase in energy demand and the utilization of fossil fuels started after World War II, in the middle of 20th century.
• The global energy demand has more than doubled since the 1970s. The magnitude of global energy demand in the 1970s was about 250 EJ. It is equal to about 6 000 Mtoe. The current magnitude of the global energy demand is about 600 EJ. It is equal to about 14 500 Mtoe.
• The global energy demand has been growing during the last five decades almost constantly with about 2% annually, from 254 EJ in 1973 to 606 EJ in 2019.

What do EJ and Mtoe mean?

• EJ = Exajoule
• 1 EJ = 1018 J= 1 000 000 000 000 000 000 J
• 1 EJ = 23.88 Mtoe = 277.78 TWh

Also the global population has grown rapidly in the last decades (see chart below), contributing to the growing energy demand. Some milestones in world population growth:

• in 1950: 2,5 billion people
• in 1987: 5,0 billion
• in 2022: 7,9 billion
• prospect for 2057: 10 billion?

Energy consumption per capita has also increased during this period, accelerating the growth in energy demand.

Growth of world population. Source: OurWorldInData.org / Max Roser, CC-BY-SA. Click to expand