In “Dry Injection of Trona for SO3 Control” (May 2010), NH4HSO4 is ammonium bisulfite.

In the June “Focus on O&M,” the engines shown in Figure 6 each have eight cylinders.

June’s “Competition for Offshore Turbine Market Heats Up” stated that drive or gearless turbines accounted for 14% of the world’s installed offshore capacity in 2009. The source of that figure was Bloomberg rather than Bloomberg New Energy Finance.

In the July “Focus on O&M,” Cardinal Unit 3 is owned by Buckeye Power.

In July’s “Circulating Fluid Bed Scrubbers Bridge the Gap Between Dry and Wet Scrubbers,” the Figure 2 and 3 schematics were reversed in print but are correct online.

POWER regrets the errors.