Emission Reductions from Power Plants Linked to Air Quality Improvements

Kentucky’s relationship with coal is long standing and remains a significant component to the state’s energy profile and economy. From mining to electricity generation, Kentucky’s coal mines are responsible for over 14,000 on-site jobs. With such close proximity to this natural resource, it’s no surprise that in 2012, ninety seven percent of Kentucky’s electricity generation came from coal-fired power plants, resulting in some of the lowest electricity rates in the nation. The secondary effect of this is Kentucky’s ability to attract and retain energy intensive manufacturing operations.

The contribution of coal to Kentucky’s economy and culture is undeniable; however, coal and its associated activities do not go unnoticed in terms of their effect on Kentucky’s environment. The combustion of any fossil fuel results in a mix of air pollutant emissions. Most concerning from coal-fired power plants are sulfur dioxide (SO2) and oxides of nitrogen (NOx). When in the presence of heat and sunlight, NOx reacts with volatile organic compounds to form fine particulate matter and ground-level ozone. Sulfur dioxide is also responsible for the formation of fine particles which can penetrate deeply into sensitive parts of the lungs. Both SO2 and NOx can aggravate existing respiratory diseases, such as emphysema and bronchitis, and can aggravate existing heart disease, leading to increased hospital admissions and premature death.

According to the Kentucky Division for Air Quality (DAQ), the electricity-generating sector alone accounts for approximately 79 percent of total surveyed air emissions from stationary sources. Nevertheless, emissions from these power plants have decreased significantly over the last 30 years.  These decreases are due to increasingly stringent National Ambient Air Quality Standards, interstate air pollution regulations, mercury air toxics standards, and the Acid Rain Program. In fact, by 2018 NOx reductions are projected to reach 76 percent below 1990 levels, while SO2 emissions are projected to reach 81 percent below from 1990 levels.

Table 1: Pollutant Reduction from Kentucky Electricity Generating Units (EGU)  DAQ EGU ChartThese decreases have contributed to the significant decline of monitored air pollution(Figure 1) and corresponding reductions in air quality related health and environmental risks. DAQ operates an air monitoring network throughout the state that assesses the air quality as compared to the national standard for each pollutant. In simplest terms, this network helps determine how “clean” the air is in Kentucky.

Figure 1: Statewide Air Quality Monitoring Trends

blog AQ trends

“It’s irrefutable that the air quality programs designed to protect public health and the environment are working,” said DAQ Director John Lyons. “The data clearly shows that establishing pollutant reductions at the source can result in air quality improvements statewide, especially for a sector as significant as electricity generation in Kentucky.”

While dramatic, there is still much work to be done within Kentucky’s electricity-generating sector. Upcoming greenhouse gas regulations, lowering of the National Ambient Air Quality Standards (NAAQS) and interstate transport regulations will all have significant impacts on both the coal mining industry and how Kentucky generates electricity.