A $240 million dollar, 12-story-tall steel tower is Alabama Power&8217;s latest investment to curb pollution at its Ernest C. Gaston plant in Wilsonville. Called a selective catalytic reduction machine, the technology is expected to remove 80 percent of nitrogen oxide (NOx) from Gaston&8217;s emissions.

NOx combines with chemical compounds from sources like petroleum, paint thinner and dry-cleaning solvents to form ozone. Operating much like a catalytic converter in a passenger car, the machine allows gases to pass through a myriad of ducts and pipes that transform NOx into harmless nitrogen and water.

The Gaston plant houses the sixth SCR system built by Alabama Power since 2002. Four additional units operate at coal plants in Jefferson and Walker counties.

Due in part to the reduction machines, Alabama Power witnessed a 64 percent drop in ozone-season NOx emissions over that last ten years.

&8220;We are very proud of it. It has been a good project,&8221; said Willard Bowers, vice president of environmental affairs. &8220;This is a significant achievement because we&8217;ve reached this reduction while increasing production to serve Alabamians&8217; needs.&8221;

The SCR unit will operate only during ozone season, which runs from May 1 through the end of September. According the Bowers, Alabama Power has the option of running the machine yearlong if federal restrictions grow tighter.

&8220;Ozone is not a problem outside the summer months,&8221; said Bowers. &8220;In winter time you don&8217;t have the formulation of ozone.&8221;