11-19: AEP's Experience With Polyester FRP Structure Cooling TowersThe first polyester fiberglass structure cooling towers were placed in operation on the AEP system during the period of 2008 to 2010. One of these towers is a counter flow design while the other four towers are cross flow designs. Surface blisters were found on 15% to 20% of the columns in two towers after 18 months of service. A majority of the fiberglass bearing pads have failed in 3 towers which caused the bottom of many of the pipe columns to