This time I would like to dwell a little bit on energy “consumption” and its relation to Gross Domestic Product (GDP) creation. (In fact, the term “energy consumption” is misleading, as energy cannot be destroyed nor created, according to the First Law of - more about that later.) For this discussion, I’m using data from the 2006 Report of the International Energy Agency. There are several ways to look at the raw data, three of which are described below.
First, one feels intuitively that the amount of energy that a nation uses is related to its productivity, as expressed in its GDP and its population, which of course drives GDP. Therefore, in order to compare nations with different outputs and populations, it seems wise to divide both consumed energy and GDP by population. This is expressed in Figure 1 below.
Figure 1. GDP versus energy consumed for selected nations and regions
What we notice is the huge range in power levels (in KW/capita) between the lowest consumer (India) and the highest (USA). In the USA, each citizen needs an average power level of more than 10KW every second to keep the society going (this includes everything: transportation, work, food, housing, leisure, etc.). But when we look to productivity levels (expressed as GDP/capita), we see that the productivity of the USA (ca. $36,000/capita) is more than 70 times than that of India (ca $500 /capita). Based on that, the USA is perhaps not such a bad performer in terms of energy efficiency (10KW/capita vs. about 1KW/capita for India), but more on this later. There seems to be a rough overall correlation between GDP/capita and energy/capita. This is understandable, since higher productivity per individual will cause a higher energy need for each.
There is, however, another interesting fact. In the example above, we compared an underdeveloped country with a highly developed one, which may be like comparing apples with oranges. So let’s compare Japan with the USA. The productivity per capita of both countries is comparable and actually are the best in the world, from a productivity point of view. Yet Japan needs only half of the kilowatts that the USA needs! If the USA could be as frugal with energy as Japan, that would instantly solve its dependence on oil imports and vastly decrease the production of greenhouse gases! On that score, Japan emits 9.5 tons of CO2/capita, whereas the USA emits 19.7 tons per capita, roughly proportional to the energy consumption ratio of the two countries. (For perspective, consider that worldwide per-capita CO2 emission is only 4 tons (4000 kg) per year!)
Now let’s look at the problem from the angle of energy efficiency, as in Figure 2.
Figure 2. Energy efficiency of selected countries and regions
In this figure, we plotted total primary energy supply (TPES) divided by GDP for several nations and regions. The TPES is a calculated number where factors such as energy production, imports, exports and stock changes are taken into consideration. It is expressed in millions of tons of oil equivalents (MTOE) and can be converted into GWh: 11630MTOE = 1GWh. The more to the right you are in the graph, the better your energy efficiency.
What we notice is that the industrialized countries are working most efficiently, with Japan in the lead. Russia is doing the poorest job in terms of energy efficiency, whereas less industrialized regions are factors lower than the best performers. This is an important fact, because rapidly industrializing countries such as China and India can improve greatly by implementing known methods from the Western nations. However, let’s not fool ourselves. While it’s good to strive for energy-efficient production, the impact on the climate is simply proportional to the absolute amount of energy consumed. Have a look at Figure 3.
Figure 3. Absolute energy “consumption” per nation or region
From Figure 3, I believe the conclusion is clear: global climate change can be addressed only by international measures. And it can be managed only if we humans bring down our total energy requirements. This can be done partly with greater efficiency, and (this is the hard part) by decreasing usage as well. The big users of energy such as the USA, China, and Europe must act together as responsible planetary citizens.
© Copyright 2007, John E.J. Schmitz