Helping the Lights Stay On: Cofiring biomass with coal is a relatively inexpensive way to extend U.S. energy resources.

This article explains the process of cofiring biomass with coal that could be a relatively inexpensive way to extend energy resources in the United States. While biomass-fired plants have been a part of the scene for some time, they are relatively small, 25–50 MW, and often address specialized local conditions. In California, they are helping to reduce air pollution by replacing the open field burning of agricultural residue. Adapting coal-fired units to cofire biomass requires additions and modifications, but compared to starting a new plant from scratch, it is a relatively low-cost, low-risk method to add renewable energy to the plant fleet. In a cofiring application for a pulverized coal plant, biomass can replace 20% of the coal being used. With cofiring, power generation is not dependent upon biomass, so there is a lower risk of technology entry than with other renewable energy options. Biomass can be used when supplies are available.