Time of Use Rates
Time of Use (TOU) rates are designed to give electric utility customers options to save money by lowering electricity bills by adjusting their use patterns to use more electricity (e.g. by running high-energy use appliances) when the rate is reduced and less during on-peak hours. On-peak periods are set when demand is highest and costs are greater to generate and deliver energy. When demand is low, the cost of electricity is generally lower because there is less stress on the electricity grid and cheaper energy sources are available. For example, wind generated electricity is typically more available overnight and it is less expensive to produce and distribute at that off-peak time.
Current Open Proceedings
Public Service Company of Colorado (Xcel Energy)
Currently, Xcel Energy residential electric customers are billed on TOU rates according to three time periods: On-Peak, Off-Peak and Mid-Peak. On Sept. 3, 2024, Xcel Energy filed for approval of new TOU rates in Proceeding No. 24AL-0377E. The Commission reached a final decision on this proceeding in May of 2025. The new TOU rates will go into effect in October of 2025.
PUC-approved TOU Rate Structure (Effective Oct 25)
New TOU Times:
- On-Peak: 5PM to 9PM on non-holiday weekdays, year-round
- Off-Peak: all other hours
Xcel Energy customers can opt out of Xcel Energy’s TOU rates and elect to take electric service on a flat rate. The flat rate is higher than the TOU off-peak rate and lower than the TOU on-peak rate. The Commission also directed Xcel to develop an online calculator so that customers can compare their bill under TOU rates to a flat rate to allow them to make a more informed decision based on their actual usage.