As much as 20% of U.S. coal-fired electricity generation is expected to be shut down over the next three to five years, according to a recent report funded by the Department of Energy. The study, by the consulting firm ICF International, examined the eastern region of the U.S., which is home to 85% of U.S. coal-fired power plants. It estimated that up to 60 gigawatts of electrical capacity will be retired. Driving the retirements is a combination of power plant age; the costs of installing long-delayed modern pollution controls; inexpensive fuel alternatives, particularly natural gas; and expected limits on carbon dioxide emissions. Most of the units in the eastern region are more than 50 years old and lack basic sulfur dioxide controls, according to the report. The study also found that availability of carbon capture and sequestration technologies is unlikely in the near future. Overall, it described a shift to natural gas generation in the U.S., predicting that carbon capture technologies are more likely to be tried first on natural-gas-fired power plants, not coal-fueled ones.