Figure 1.
The first thing to look at is how energy is divided between residential, commercial, industrial, and transportation uses. A pie chart shows this in Figure 1. In the U.S., 32% of energy is used by industry, 29% by transportation, 21% by residences, and 18% in commercial spaces such as stores, universities, and office buildings.1
Figure 2.
We can compare these numbers to the values for Europe2 (Figure 2) and China (Figure 3), using the Energy Information Administrations's 2009 International Energy Outlook.3 One can see that both Europe and China use a larger fraction of their energy on industry than does the U.S. China's energy use, in particular, is heavily skewed toward industry.
Table 2 breaks the numbers down into per capita energy use in each sector. The numbers don't quite total up the same as the first page, in part because these are for different years, but there is enough information to get a general idea of some trends.
Figure 3.
For instance, the U.S. uses about 60% more per energy per person on industry than Europe, and 2.4 times more energy per person than China. However, from the previous page, we already found that the average U.S. citizen uses twice the energy of the average British or German citizen. The large gap in energy use really comes from residental, commercial, and transportation. In each sector, we use about three times more energy than the average European.
This information gives us some ideas as to where we can look for efficiencies. Granted, this will not be easy, but Europe could provide a model for halving our energy use. Many of the efficiencies in Europe are a response to its higher population density. Europe and the U.S. have roughly the same land area, but Europe's population is twice as large. However, Europe also has laws and regulations that encourage conservation. In the following sections, we will look at where energy goes in the U.S. sector-by-sector.
| Table 1: Per Capita Energy Consumption by Sector | ||||
|---|---|---|---|---|
| Country | Residential | Commercial | Industrial | Transportation |
| (MWh) | (MWh) | (MWh) | (MWh) | |
| United States (2007) | 21.2 | 17.9 | 31.4 | 28.3 |
| Europe (2006) | 9.6 | 6.3 | 19.3 | 9.8 |
| China (2006) | 1.8 | 0.7 | 12.7 | 1.3 |
Notes and References
(1) In examining these numbers, it is useful to keep in mind that electricity, which makes up 40% of energy use in the U.S., is currently rather inefficient to generate. Typically only 32% of the enery used to generate electricity is useful; the rest is lost in the process of generating, transmitting, and distributing the electricity. Commercial and residential users rely heavily on electricity, so about half of their energy consumption disappears into electrical losses. The charts on this page include all of the energy consumed by a sector, including estimates for electrical losses.
In the later charts, we will only look at the useful energy, and ignore the losses. By cutting the amount of useful energy we use, we would also cut the energy lost while generating the energy.
(2) We use the numbers for European countries in the Organisation for Economic Co-Operation and Development. The European members are Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Poland, Portugal, Slovak Republic, Spain, Sweden, Switzerland, Turkey, and the United Kingdom. The total population of OECD Europe countries in 2005 was 534 million people, according to the CIA World Fact Book, via Nation Master.
The remaining OECD members are Australia, Canada, Japan, Korea, Mexico, New Zealand, and United States.
(3) We have numbers for 2006. The table we found is for delivered energy, so the table entries do not include electrical losses. There is a line item for electrical losses, however, so we find that electricity is genererated and distributed with 30% efficiency in China, and 33% in Europe. Therefore, for each sector, we have increased the electrical energy used by factors of 3.5 and 3.0 for China and Europe respectively.