American Electric Power (AEP) says it will expand its Trent Mesa project in west Texas by adding 13 more 1.5 MW turbines to the 87 already going up near Abilene, but the project completion date has slipped from this month to the fall. The 20 MW expansion to 150 MW will increase AEP's investment to about $160 million. TXU Utilities will buy the additional output. It says the Trent Mesa project is one of four renewables projects with which it has contracts. The combined 383 MW output of the projects is more than twice the renewable energy requirement of the Texas Electric Choice Act.