Frequently Asked Questions
- Why would Idaho Power need to resort to rotational outages?
- What are power generation reserve requirements?
- What is a rotational outage?
- How does a rotational outage work?
- How will I know if a rotational outage is going to happen?
- How are rotational outage areas identified?
- Could one customer’s power be out, but a neighbor across the street still have electric service?
- What should I do if my power is out for substantially more than two hours?
- What’s the difference between a rotational outage and an emergency or unplanned outage?
- How can I get more information about rotational outages?
- How can I prepare for a rotational outage?
- Could a rotational outage continue into the night?
- What about driving in outage areas?
- What about using a generator?
- Where can I find out about energy saving tips for my home?
- Where can I find out about energy saving tips for my business or office?
- How can I protect my equipment during a rotational outage?
1. Why would Idaho Power need to resort to rotational outages?
Idaho Power plans to meet the electricity needs of its customers during summer and winter (peak load seasons) and is doing everything possible to avoid a rotational outage situation. We are confident that we will keep the lights on in our service area.
We are careful to keep our electric load (demand) and resources (power supply) in balance.
We see our supply of power as secure and are making every effort to ensure it is adequate. However, we cannot guarantee that we would not be impacted by unforeseen power supply problems or equipment problems in the region.
Idaho Power must continually maintain additional power generation reserves of approximately six percent above what is required to serve customers.
But the sudden loss of major generation or transmission facilities within Idaho Power's system may require operators to quickly disconnect portions of our power distribution grid, and as a result, interrupt customers' service in order to keep supply and demand in balance and preserve overall system reliability. The public will be notified as quickly as possible if rotational outages are required, including information on expected duration. Idaho Power's Corporate Communications Department would initiate public communications via radio, TV and newspaper news organizations and this Web site.
2. What are power generation reserve requirements?
Idaho Power must continually maintain additional power generation reserves of approximately six percent above what is required to serve customers. This ensures the system can adjust to unexpected changes — that occur within a reasonable range — in demand for electricity and/or its production.
The Western Systems Coordinating Council requires the company to maintain this reserve to protect the reliability of western North America's electrical grid in the event of transmission or generation outages.
When these types of outages occur, Idaho Power uses some of its power generation reserves to continue to provide reliable service to customers. If the reserves drop below the required level, then Idaho Power must implement rotational outages until reserve levels are once again restored.
3. What is a rotational outage?
It’s a temporary and scheduled electric outage lasting about two hours, depending on circumstances. In the event this was necessary, Idaho Power would manage and rotate the outages to protect the overall electric system.
Rotational outages generally happen for one of the following three reasons:
- Insufficient supply of electricity for a given area
- Loss of a generating facility
- Loss of a major transmission line
For example, if a transmission line that brings power to Idaho was lost on a hot summer day, demand might quickly exceed the supply of power.
4. How does a rotational outage work?
Idaho Power has identified feeders available for use in rotating outages. A feeder is an overhead or underground electrical line that supplies power to a combination of residential and/or commercial customers within a given geographical area. These feeders have been arranged into areas. Each area includes a number of feeders that comprise approximately 100 megawatts of electricity usage per area, with each feeder generally serving between 800 and 2,000 customers.
Residential, irrigation and commercial customers are connected to distribution lines or circuits within these areas. The amount of power our system engineers designate for curtailment will determine the number of areas interrupted at any one time. In rotational outages, we temporarily turn off distribution circuits. After about an hour, another set of circuits is turned off and the previous circuits are restored. Each outage is expected to last about two hours. That area's power is then restored while the next areas on the list is then interrupted to maintain the appropriate level of demand. Once an area has been used in a rotating outage, it is moved to the bottom of the list.
5. How will I know if a rotational outage is going to happen?
As soon as Idaho Power determines rotational outages are necessary, Idaho Power’s Corporate Communications Department will contact the news media, especially radio and television stations, which are encouraged to broadcast the news immediately. This information also will be posted to this Web site and recorded on the toll-free number for your area.
6. How are rotational outage areas identified?
Idaho Power’s service area is divided into five operating regions. Each region has its own dispatch office to manage their part of the grid. Each region has a team of technical and customer service specialists to work closely with customers affected by rotational outages. The regions are listed below:
- Boise - Meridian, Mountain Home
- Canyon County - including Caldwell, Nampa, and the Jordan Valley, Ore., areas
- Payette - Ontario, McCall, Riggins areas
- Pocatello - Pocatello and Salmon areas
- Twin Falls - including Magic and Wood River valleys
Each area has a team of technical and customer service specialists who are expert with their communities' and customers’ needs. They will work with customers to help implement outages safely.
7. Could one customer’s power be out, but a neighbor across the street still have electric service?
Yes. It’s possible for neighbors to be on different feeders. A feeder is an overhead or underground electrical line that supplies power to a combination of residential and/or commercial customers within a given geographical area. Feeders do not necessarily align with streets, neighborhoods or community boundaries. Two different feeders could easily serve one street. A feeder can serve up to 2,000 customers.
8. What should I do if my power is out for substantially more than two hours?
First, find out whether your neighbors who were impacted at the same time as you have electrical service restored. If they also are without power, call the toll-free number for your area and Idaho Power will send out a crew to investigate. If neighbors do have service, you might have an isolated electrical problem in your home or business.
9. What’s the difference between a rotational outage and an emergency or unplanned outage?
Unplanned or emergency storm-related or accident-caused power outages normally last only a few minutes but can extend to hours. The average Idaho Power customer is without power less than two hours during an entire year. Rotational outages are outages caused by a short power supply, loss of a generating facility or loss of a major transmission line. Rotational outages generally last about two hours, depending on circumstances.
10. How can I get more information about rotational outages?
Information about rotational outages is available by calling our toll-free number 1-800-488-6150. Boise and Treasure Valley customers may call 388-2323. This phone number also is used for any emergency or unplanned outage caused by storms or traffic accidents.
When you call to report an outage, our customer service representatives will ask you for the following information:
- Your name, your business’ name (if applicable), address and telephone number
- The approximate time power was interrupted
- If the entire area is without power, or just your business or home
- If you saw or heard anything unusual when the power went out
- If you can see any power lines on the ground
Remember: If there are any lines on the ground, stay at least 10 feet away. The lines could still be energized and dangerous.
11. How can I prepare for a rotational outage?
See how to prepare for a rotational outage on the Outage Tips page.
12. Could a rotational outage continue into the night?
Yes. It is possible a rotational outage could occur during the night. An Energy Emergency Alert 3 could occur at any time.
13. What about driving in outage areas?
Minimize driving in an outage area. When driving through a rotational outage area, traffic lights may not be functioning. These intersections should be treated as four-way stops.
14. What about using a generator?
If you have a portable generator, never attempt to connect it to house wiring. This could feed electricity back into Idaho Power’s utility lines and seriously injure or kill Idaho Power crews working to restore your power.
Instead, carefully follow manufacturers’ instructions on plugging appliances into a temporary generator. Always use it in a well-ventilated area and install it according to electrical codes and manufacturers’ instructions.
To avoid the risk of personal injury, only a qualified installer or licensed electrician should connect a generator to utility, home or business wiring.
E-mail us if you’d like Idaho Power’s “Using Portable Generators” brochure. It gives more details about generator safety recommendations and guidelines. To request a copy, email Iwebster@IdahoPower.com.
15. Where can I find out about energy saving tips for my home?
Idaho Power offers an Energy Planner brochure complete with conservation tips, meter-reading information, energy-saving suggestions and a glossary of electricity terms.
16. Where can I find out about energy saving tips for my business or office?
Idaho Power has a publication called “10 Ways to Conserve 10%” with information about how to conserve energy for business, industry, government and institutions. To request a copy, e-mail Iwebster@IdahoPower.com.
17. How can I protect my equipment during a rotational outage?
It is important to monitor Idaho Power's schedule of rotational outages via its Web site because it is your responsibility to protect your equipment from power outages and fluctuations. You should protect highly sensitive equipment by installing sensors designed to shut off the power supply if substantial power fluctuations occur.
Unprotected equipment should be unplugged, or the circuit breaker shut-off until the power is restored. We suggest leaving one light on so you’ll know when the power has been restored.
Once the power has been restored for about 10 minutes, equipment should be brought back online in stages. Energizing one breaker or fuse (or large piece of equipment) at a time and ensuring the equipment is functioning properly before moving to the next breaker or fuse provides additional protection for your equipment. In addition, waiting 10 minutes before resetting the breakers or fuses will help eliminate problems that can occur if equipment is brought back on-line before Idaho Power’s system is stabilized.
If doors are kept closed on refrigeration equipment, cool temperatures can be maintained for several hours. Dry ice can be used to protect the contents during extremely long outages. Use gloves when handling dry ice and use caution not to place it directly on the contents.
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