Interruptible Service Option Credit (ISOC)

Business customers in Colorado can save on a large scale with our Interruptible Service Option Credit (ISOC). To qualify, you must agree to reduce your electric demand at our request during peak demand.

During periods of peak demand, such as hot summer days, our system may require more power than is normally available. ISOC customers help reduce the amount of electricity our customers need which helps us meet demand requirements at critical times.

The more load you agree to control, the more you’ll save. In return for participating, you receive a monthly credit on your demand charges, which could amount to substantial savings for your business.

If you’re interested in ISOC, call your Xcel Energy account manager or our Business Solutions Center at 1-800-481-4700. We can help you determine whether ISOC is a good fit for your business.

When you use ISOC, you can gain tremendous savings all year round on your energy bill. In return for participating, you receive a monthly credit on your demand charges, which could amount to substantial savings for your business.

Depending on how much of your demand you’re willing to reduce at our request, you can qualify for thousands of dollars in discounts on your controllable demand. See the information sheet under Additional information for credit amounts.

During periods of peak demand, such as hot summer days, our system may require more power than is normally available. ISOC customers help reduce the amount of electricity our customers need which helps us meet demand requirements at critical times.

Interruption periods typically occur as a result of capacity, contingency and/or economic constraint on hot, summer days between June 1 and September 30. However, these events can occur during any season or during a rare system emergency.

All interruptions will last a minimum of 4 hours, unless a shorter interruption option is selected.

The more load you agree to control, the more you’ll save.

• Year-round energy savings often add up to thousands of dollars in discounts on your controllable demand (see the information sheet under Additional information for credit amounts).
• Choose the amount of interruption appropriate for your facility.
• Your credit is tied to the number of hours you contract to be interrupted each year and to the advance notice option you select.
• You can join the program without sufficient history to prove your business has the 300kW of controllable load.
  • Your contract interruptible load is the median of your maximum daily hourly demands, which occurred between noon and 8 p.m. on Monday through Friday (excluding weekends and holidays) from June 1 through Sept. 30 of the previous year.
  • Your interruptible demand is the maximum hourly demand used during the month that occurred between noon and 8 p.m., less any firm demand.

If you’re interested in ISOC, call your Xcel Energy account manager or our Business Solutions Center at 1-800-481-4700. We can help you determine whether ISOC is a good fit for your business.

Note: You can join the program for the current year anytime before May 31st.

To qualify for ISOC, you must:

• Be an electric business customer of Xcel Energy in Colorado.
• Agree to interruptible conditions per program requirements and conditions.
• Be able to maintain 300 kilowatts (kW) of interruptible electric demand.
• Install a phone line connected to your meter at your own expense.

If you have any questions regarding the ISOC program,

• Contact your Xcel Energy account manager
• Call 1-800-481-4700
• Email us

For credit amounts or more details on ISOC, see the