How Is Electricity Made from Coal?
CPS Energy ships low-sulfur coal by train from Wyoming to the J.K. Spruce Plant in south Bexar County. Individual rail cars each carry a maximum of 120 tons of coal. Once the train arrives at the plant, the coal is unloaded and stored. Coal enters the plant by conveyer belts that drop the pea-sized pieces into five silos. At the bottom of each silo, a pulverizer grinds up the coal in to a talcum-powder consistency. The coal is grinded to make it easier to deliver and burn as a fuel. Large fans blow the coal powder into a boiler that stands 20 stories high. The coal fuels a massive fireball that can reach 3,000 degrees Fahrenheit. Steam pipes in the boiler carry ultra pure water that has been pumped from a nearby cooling lake and treated. The heat of the furnace converts the water into steam. At a temperature of 1,005 degrees and a pressure of 2,400 pounds per square inch (PSI), the steam is sent over a turbine through a series of pipes. Low pressure, intermediate pressure and high pres
