There is some good news when it comes to air pollution, a recent report found. Sulfur dioxide, nitrogen dioxide and carbon dioxide emissions are declining. The report by the sustainability advocacy group Ceres analyzed 100 power producers across the U.S., and based its findings on generation and emissions data from the Energy Information Administration and the EPA.
Nitrogen dioxide and sulfur dioxide emissions cause serious health effects. Nitrogen dioxide causes eye, nose, and throat irritation, according to the EPA. It can also cause impaired lung function and increased respiratory infections in young children. The primary sources are combustion processes. Short term sulfur dioxide, ranging from five minutes to 24 hours, is linked to respiratory problems including increased asthma symptoms. Power plants are the largest source (73 percent) of sulfur dioxide emissions.
In 2010, power plants were responsible for about 64 percent of sulfur dioxide emission, 16 percent of nitrogen dioxide emissions, and 40 percent of carbon emissions. However, that same year, sulfur dioxide and nitrogen dioxide emissions were 68 percent lower than they were in 1990, which the report attributes to programs implemented under the 1990 Clean Air Act (CAA). Both kinds of emissions continued to decrease in 2011 and 2012.
The power sector accounts for more carbon emissions than any other sector, including transportation. Carbon emissions increased by five percent between 2009 and 2010, but decreased by about five percent in 2011, which the report attributes to a “shift away from coal.” Coal-based electricity decreased by over six percent between 2010 and 2011.
During the same period, natural gas power generation increased by 25 percent. Electricity generation from natural gas fired plants is now virtually equal to generation from coal fired plants, with each providing 32 percent of total generation in April 2012.
Since January 2010, plant owners have announced retiring about 40 GW of coal plants or 12 percent of the country’s coal-fired plants due to “changing market conditions” which include the costs associated with new environmental requirements. That is not exactly good news as natural gas is a fossil fuel.
There is another bit of good news contained in the Ceres report. Renewable energy production more than doubled from 83 million megawatt hours (MWh) in 2004 to 195 million MWh in 2011.
Photo: Flickr user, Rennett Stowe