Growing Demand

In the last 200 years we have experienced exponential population growth of 700%: from one billion in 1800 to 7 billion in 2012. The image below (Allianz) shows just how dramatic this increase is, particularly compared to the growth in the 18th century which was around 30%. In addition, we can see the population is expected to continue growing, although the rate of growth may reduce slightly.

Figure 1: Population of the Earth (Allianz)

So what has caused this rapid expansion and how does it link to energy supply and demand? The increase in population in the last 200 years has been enabled by a number of factors such as production of fertilizers for industrial farming, the increased availability of clean water and advancements in healthcare and technology (Ellis et al 2010). These factors have reduced mortality rates and increased life expectancy resulting in a bigger population. The fundamental link between these different factors is their dependence on a constant supply of cheap energy. The correlation between population and energy consumption is clearly highlighted by comparison between increasing population and demand for energy. This graph only displays the data for the USA (Energy Information Administration) but the global energy consumption follows a similar trend (Smil 2008).  

Figure 2: US Energy Consumption 1775-2012 (Energy Information Administration)

Where is the demand coming from? In the early part of the 20^th century, much of the demand came from the United States and Western Europe. Increasing development in other areas of the world mean that the US and China are now the biggest consumes of energy. The following image has been created by The Guardian (Guardian Datablog) using data from the (2012 BP Statistical Review of the World) and shows the global consumption of oil in 2009, listing the number of barrels consumed and percentage change from 2008-2009. It will probably come as no surprise that the rapidly industrialising countries such as Brazil, China and Saudi Arabia are catching up the highly developed countries in their demand for energy.    

Figure 3: Global Oil Consumption (Guardian Datablog)

Growth of ‘the middle class’ and increasing quality of life means that more energy is being consumed per person in developing countries. Therefore, even if global population growth slows, the demand for energy is predicted to increase as more countries achieve higher stages of development (Steffen et al 2011). Meeting these energy demands is shaping up to be one of the biggest challenges faced by society and I will examine some of the potential options over the course of this blog.