Pennsylvania is now the fourth largest coal producer in the United States, following Wyoming, West Virginia and Kentucky. Two kinds of coal are mined in Pennsylvania: anthracite (hard coal) and bituminous (softer coal). The latter is the most mined coal in Pennsylvania. Almost all of the nation's anthracite coal is found in eastern Pennsylvania. Anthracite is coal with the highest carbon content, between 86 and 98 percent. Today, coal's most important contribution to Pennsylvania’s society is electricity. Coal-fueled power plants generate about 52 percent of the electricity nationally and 60 percent in Pennsylvania. Actually, 97.3% of Pennsylvania energy production comes from coal or nuclear sources. The other small fraction of Pennsylvania energy comes from hydroelectric, oil & natural gas.

        Because the use of electricity as a major energy source is increasing – it accounts for more than half of the energy use outside the transportation sector – coal's role in Pennsylvania is expected to grow. But as a fossil fuel, coal also contains carbon, which combines with oxygen to form carbon dioxide (CO₂) during the combustion process. CO₂ is one of five major so-called "greenhouse" gases, which help trap radiated heat back to the earth's surface.

        As the nuclear and oil industries, coal industry got its start in Pennsylvania, leaving behind a legacy of damage. The environmental legacy of hundreds of years of coal mining in Pennsylvania is acid mine drainage from old mining operations which is the single largest source of water pollution by far in the state. Pennsylvania leads the nation in acid mine drainage and in acid rain, due to leaking mines and the effects of coal burning, respectively. Pennsylvania is #2 in toxic air emissions from coal mining/processing, #3 in toxic air emissions from coal and oil electric utilities (source: Pennsylvania: A Leader in Toxic Releases). Pennsylvania's coal plants are #1 in mercury emissions and #2 in sulfur dioxide (SO₂) emissions (contributing to acid rain). They are also #6 in Carbon Dioxide (CO₂, a greenhouse gas) emissions and #9 in nitrogen oxide (NO_x, another contributor to acid rain) emissions (source: Lethal Legacy: The Dirty Truth About The Nation’s Most Polluting Power Plants). Does this have something to do with Pennsylvania being one of the only four states in the nation losing population, in the last five years or so?

        Another fact important to consider here is that the electricity industry is changing. In Pennsylvania as well as some other states, customers can now choose their electricity supplier, selecting electricity generated either from polluting fossil fuel and nuclear plants or from cleaner, environmentally preferable, or "green" sources. With electric competition in Pennsylvania, consumers are now expressing their desire for "clean" energy sources. People are willing to pay extra for energy that doesn't pollute. Thus, Pennsylvania, as one of the pioneers in the fossil fuel industries developments, now has the opportunity to make a difference and become a leader in the development of renewable energy.