Billing & Payments

Understanding your bill: Transmission Cost of Service

Learn more about the line items on your bill

You know you pay for the energy you use, but what are all those other items on your bill? Our understanding your bill series helps break it down.

Bill sample highlighting the Transmission Costs of Service line item.
Bill sample highlighting the Transmission Costs of Service line item.

Transmission Cost of Service (TCOS)
This line item reflects the cost incurred for accessing the state’s transmission system to deliver power. The amount that PEC pays every year is set by the Public Utility Commission of Texas (PUCT) and is based on the statewide transmission costs and PEC’s total energy demand during our Four Coincidental Peak events. The rate shown on your bill is approved by the PEC Board of Directors and set at a level that we can collect the annual amount owed to access the transmission system.

Four Coincidental Peak (4CP)
PEC’s transmission costs are partly based on how much electricity our members use during four 15-minute peak events: periods of high use during June, July, August, and September, usually occurring between 2-7 p.m. These are referred to as 4CP events, and they determine PEC’s share of our statewide transmission costs the following year. So, if our members’ energy use is high during the 4CP events, PEC will be charged more in transmission costs the next year — and as that cost is passed directly through to members, you’ll see a higher transmission cost on your bill at that time.

Want a lower TCOS? You’ve got the power
We call it Power Rush Hour: When we all work together to reduce our energy use during peak times, we can help PEC have a lower share of statewide transmission costs. Shift use of large appliances like dishwashers, washing machines, and your HVAC system outside of the peak hours of 2-7 p.m. in the summer months, and learn more Power Rush Hour peak reduction tips here.