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US CO2 emissions dropped in 2012 EIA says factors such as improved energy efficiency, increased use of natural gas and lower electricity demand caused decline Alan Bailey Petroleum News
Although carbon dioxide emissions into the atmosphere continue to cause major concerns over global warming and ocean acidification, a recent drop in emissions in the United States perhaps demonstrates the possibility of a major developed country reducing rather than increasing its carbon footprint.
According to a recently published report from the Energy Information Administration, or EIA, U.S. carbon dioxide emissions fell by 3.8 percent in 2012, placing the 2012 emissions 12 percent below the emissions level in 2007, the year in which those emissions peaked after a multiyear climb. And although a sharp decline in emissions in 2009 can, at least in part, be attributed to reduced emissions-generating activity in the U.S. in the recession that followed the 2008 financial crisis, the EIA points out that the drop in emissions in 2012 occurred in a year during which the U.S. economy grew.
“(U.S.) energy-related carbon dioxide emissions have declined in five out of the last seven years,” the EIA report says.
Energy intensity EIA says the drop in emissions in 2012 resulted to a substantial extent from a drop in U.S. energy intensity, a measure of the efficiency with which the country uses its energy resources. In fact the U.S. energy intensity, calculated by dividing the country’s total energy use by total economic activity, as measured by the gross domestic product, dropped by 5.2 percent in 2012. That reduction in energy intensity drove a corresponding drop in U.S. carbon intensity, the weight of carbon emitted per unit of economic activity. However, a fall of 3.5 percent in the carbon intensity of U.S. power generation came largely as a result of an increase in the use of natural gas relative to coal in power stations — the burning of gas generates less carbon dioxide than the burning of coal. This decline in power generation-related carbon dioxide happened despite a slight fall in the use of renewable energy, where a drop in hydropower output more than offset an increase in wind power, the EIA report says.
The carbon intensity of the U.S. economy has been dropping fairly consistently year by year since records began in 1949, the report says.
Other factors In terms of total carbon dioxide emissions, a growth in the U.S. population coupled with an increase in the U.S. production output per-capita of that population somewhat offset the energy and carbon intensity gains in 2012, the report says. At the same time, relatively mild weather during the winter heating season caused a reduced demand for heating fuel and, hence, a drop in residential emissions during the early part of the year.
In 2012 energy losses in electricity systems declined by 4.8 percent, implying improved efficiency in electricity generation, transmission and distribution. At the same time, domestic electricity consumption dropped 3.4 percent, taking carbon dioxide emissions resulting from residential electricity use down to levels last seen in the late 1990s, the report says. And, although vehicle use in the U.S. in 2012 appears to have been similar to that in the previous year, increasingly energy efficient vehicles are entering the market, with transportation-related carbon dioxide emissions remaining well below levels seen in 2007.
Looking at trends going back to the late 1990s, it appears that an annual growth in U.S. carbon dioxide emissions until 2007, the year that emissions peaked, was essentially driven by a steady increase in U.S. per-capita production output. Between 2007 and 2012, on the other hand, per capita output remained about flat, so that, with the carbon intensity dropping, total carbon dioxide emissions also fell.
Increasing globally According to information on the EIA website, global carbon dioxide emissions, thought to be the primary driver of global warming, are expected to rise by about 1.9 percent annually, primarily because of the use of fossil fuels in emerging economies such as India and China. However, the website also indicates that total emissions from these emerging countries still lag behind the total emissions from established industrial countries, including the United States.
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