The AES Medina Valley cogeneration plant in Illinois, USA, has now come on line to provide electricity, steam heat and chilled water to Caterpillar’s Mossville site and electricity to its Mapleton foundry. Motive power is supplied by three Solar Turbines Titan 130 gas powered turbines each driving a genset rated at 12.2 MW; and two steam turbines supplying 8.9 MWe. In addition to 45 MW of electricity the plant can provide up to 410 000 lb/hr of steam, and 7200 tonR capacity of chilled water.
The chiller plant includes the two steam generators, a York CodePak GED natural gas engine driven chiller (powered by A Cat 312 engine) and two York electric chillers. In the winter steam is used for heating and manufacturing processes; in summer it powers the absorption chillers to provide air conditioning.
The benefit to Caterpillar has been a lowering of overall utility costs for steam and electricity. AES, who operate the site, regard it as expandable, and a model for future distributed generation plants.
