U.S. Energy Information Administration - EIA - Independent
Statistics and Analysis Today in Energy On July 7, 2011, the
Environmental Protection Agency (EPA) released the final version
of the Cross-State Air Pollution Rule (CSAPR). The CSAPR is
intended to reduce emissions of sulfur dioxide (SO2) and
nitrogen oxides (NOx) from power plants in the eastern half of
the United States by imposing state-level caps on emissions and
facilitating a limited interstate cap-and-trade program. There
are several possible strategies for reducing SO2 and NOx
emissions from coal-fired power plants: plant owners can use
lower sulfur coal in their boilers, run the plants with higher
emissions less often, retire plants without emissions controls
and run other plants, or install emissions control
equipment—primarily, flue gas desulfurization units (FGD, or
scrubber) for SO2 and selective catalytic reduction (SCR) units
for NOx. The CSAPR's SO2 limits apply to 23 states. Total coal-
fired electric generating capacity in these state