Rising 18 stories above the fields in rural Indiana, Duke Energy’s Edwardsport power plant is a technological marvel and among the cleanest coal-fired power plants in the world.
Edwardsport Integrated Gasification Combined Cycle (IGCC) station in Knox County, Ind., produced a record 3.9 million megawatt-hours of energy in 2017, a 28 percent improvement over its previous record.
Edwardsport by the numbers
- The plant produces 10 times more power, and is 70 percent cleaner, than the older coal units it replaced.
- In 2017, the plant provided power for about 500,000 homes and businesses.
- The plant uses 1.5 million to 2 million tons of Indiana coal per year, a boost for local and state economies that depend on the coal industry.
- The coal used each year supports an estimated 170 mining jobs, and the plant employs around 200.
One of two gasification combined-cycle plants in the country, and the largest, the 618-megawatt plant started producing electricity commercially in 2013. What sets it apart from other fossil-fueled power plants is its technology. The plant can produce electricity using natural gas or by using a gasifier to turn coal into syngas (synthetic gas). The syngas fuels two combustion turbine generators and a steam-driven generator, running off heat from the combustion turbines and gasifier, to produce electricity.
The syngas produced from gasification is refined to remove pollutants, including sulfur and ash. These byproducts of the gasification process are further refined to make other products for commercial use.
Slag, for example, is removed from the gasifier and can be used to manufacture concrete, roofing shingles and asphalt filler.
When Edwardsport runs on coal, it’s one of the lowest-cost power plants in the Duke Energy Indiana system, which includes natural gas, solar and hydroelectric power. Edwardsport emits less sulfur dioxide, mercury and particulates than the conventional coal-fired plant it replaced, while providing more than 10 times the amount of energy.