Seven power plants across the city use fossil fuels like coal, natural gas or a mix of fuel oil and natural gas to power homes and businesses. Natural gas, which makes up 17 percent of CPS Energy’s fuel mix, is a highly efficient source for home heating, water heating, cooking, clothes drying and other heat-generating purposes. CPS Energy relies on natural gas as an economical, complementary option for home use and also to meet short-duration, peak electric-load requirements.

How is Electricity Made From Natural Gas?

Natural gas is a clean-burning fuel produced by deposits of methane from within the Earth’s crust.

Plant operators at Arthur Von Rosenburg, a combined cycle plant, use natural gas to power two General Electric 7-FA combustion turbines. Like a jet engine, the turbines suck in air, mix it with the fuel and ignite a fireball. The hot gases from the fireball impact the blades of the turbine to cause motion, creating mechanical energy. The turbine, connected to a generator by a shaft, spins and powers the generator. At this point, the generator converts the mechanical energy into electricity before it is transmitted for customer use.

Creating electricity doesn't stop there. Instead of being wasted, exhaust gases from the combustion engine are carried into a Heat Recovery Steam Engine (HRSE), where cold water is being pumped in through pipes. The engine uses the heat of the exhaust gases or flue gases to convert water into steam.

Once steam is created in the HRSE, it is sent to a steam turbine. The pressurized steam travels over the blades of the turbine and causes it to spin. This motion, mechanical energy, is what powers the generator. The generator makes electricity.