Decommissioning coal plants

Decommissioning a coal plant is not an easy call. To make the decision, utilities' governing boards determine the composition of their generation resource portfolios, including the development and retirement of specific generation units and how their generation fleets are operated and dispatched to meet the requirements of their customers, said Carolyn Slaughter, the American Public Power Association's director of environmental policy.

As coal plants age and become less economically or environmentally viable, or as the population around the plants changes, the best option may be to decommission.

"The decision to decommission a plant is multifaceted; it depends on economics and whether there is community outcry to get rid of the plant," Slaughter said. Many utilities had a small customer base for years and are now seeing an increase in customers as people migrate back to cities. Then utilities have to reconsider where their generation facilities are and evaluate whether they should take a plant down."

Once the decision to decommission a plant is made, it can take 10 years to complete the process, depending on how the site will be reused. While some utilities decommission coal plants to switch to next-generation energy sources such as natural gas, Slaughter believes coal will continue to be a part of utilities' power production.

"Coal will still be part of the generation mix, but coal plants that remain operating will be larger units, fully equipped with state-of-the-art environmental controls," Slaughter said.

The Association is working on a white paper to help utilities that want to decommission their coal plants.