Time-Related Demand Charges apply year-round and are calculated per kilowatt (kW) according to the highest recorded demand during On-Peak and Mid-Peak hours, non-holiday weekdays. On-Peak TRD charges apply during the summer and Mid-Peak TRD charges apply during the winter. 

Facilities-Related Demand Charges apply year-round and are calculated per kilowatt (kW) according to the highest recorded demand during each monthly billing period, regardless of season, day of week, or time of day.

One way to understand demand charges is to consider an example–imagine a single light bulb running for 10 hours. Now imagine 10 light bulbs running at once for 1 hour. Both situations use the same amount of electricity, but running 10 light bulbs at once increases the load demand on the electricity grid. This makes it more expensive for us to maintain the supply of energy. In some rate plans, your business can incur costs for the extra demand.

Demand charges are based on the highest amount of electricity used within any 15-minute period during your monthly period (referred to as “Facilities-Related Demand”) and/or on your highest amount of electricity used within a specific TOU period during your monthly billing period (referred to as “Time-Related Demand”). The unit of measurement used is kilowatts (kW). Energy charges are based on the total amount of electricity used in each TOU period within a billing cycle. For energy charges, the unit of measurement is the kilowatt hour (kWh).

Customers with behind‐the‐meter (BTM) solar generating facilities may be eligible to be served on TOU rates that retain discontinued TOU periods for 10 years from the date their systems were authorized to operate. To qualify for a discontinued TOU period, you must meet the following eligibility criteria:

● Your initial solar interconnection application must have been submitted by January 31, 2017. This deadline was extended for public agency customers to December 31, 2017. 

● Your solar generating facility must be sized to offset at least 15% of your annual load.

Download the Discontinued TOU Rate Fact Sheet

You can help lower your costs by shifting energy use from the more expensive On-Peak hours to the Mid-Peak, Off-Peak, and Super Off-Peak hours of the day when TOU pricing is lower.

TOU rates better align the cost of electricity to the time it is produced and the cost to deliver it when your business needs it. Pricing will generally be higher during summer weekdays in the late afternoons and evenings.