Generating energy and distributing it to hundreds of thousands of users is a complex process. Energy is created in a variety of ways. For example, CPS Energy uses a diverse menu of fuels, including coal, natural gas, nuclear power and renewable energy, to provide reliable electrical service to its customers. Once this energy is generated, it must be delivered through a sophisticated distribution system before it reaches your home or business.

Step One:
Stepping Up the Voltage
Electricity is generated at 20,000 volts at a typical power plant, generating station or wind farm. After electricity is generated, it first travels through a transformer that "steps up" or increases the voltage to either 138,000 volts (138 KV) or 345,000 volts (345 KV) to allow it to travel more efficiently over a long distance through large transmission lines carried by steel transmission towers. CPS Energy maintains more than 1,400 miles of transmission lines and over 6,600 transmission towers.

Step Two:
Stepping Down from Transmission
to Distribution
Transmission lines carry ramped-up electricity to distribution substations located throughout our 1,566-square-mile service area. Banks of transformers at more than 100 substations "step down" or decrease the electricity's voltage to 34,500 volts (34.5 KV) or 13,800 volts (13.8 KV) so it can travel through smaller distribution lines and make its way to specific residential and commercial districts throughout the service area.

Step Three:
Heading for Home
More than 7,500 miles of distribution lines across Greater San Antonio branch out through neighborhoods, sending the electricity through overhead or underground power lines. The power lines connect to transformers located on “telephone” poles or underground near a home or business. Transformers, more than 206,000 in our customer service area, reduce the voltage of electricity again so it can be safely delivered into your home and business.

From transformers, electricity travels into buildings through wires called service drops. The service drops connect to a meter box, which measures the amount of electricity being used by a customer. The drops also connect to all of the wires that run inside a home or building’s walls to outlets and switches.

When an electrical device is plugged in, electricity flows from electrical wires in the wall through a plug's metal prongs, which then carries power through the appliance cord to the motor of the appliance. After powering the device, it then flows back through the appliance cord to the outlet, out to the wires and into the grid again.