Understand the grid
Not every grid headline means the same thing
"The grid is in trouble" can describe a tree on a line down the street, a tight evening for a regional operator, or a report about the next ten years. These are different situations, reported by different organizations, and they call for different actions.
What this page is
A plain explanation of the terms you will see in outage maps, news stories and official notices. It does not show current conditions. To find your utility's outage map and reporting line, start with your state.
Seven things that get called "grid trouble"
A local customer outage
Your lights are out, and maybe your neighbors' too. Most outages come from damage to local lines, such as storms, falling trees or a vehicle hitting a pole. Your delivery utility repairs these.
Regional grid strain
A grid operator may warn that supply is tight, often on very hot or very cold days, and ask people to use less power. A conservation appeal is a warning about risk. It is not an outage, and most homes keep their power.
Voltage reductions and brownouts
A utility or operator can lower voltage slightly to reduce demand. Lights may dim. Treat a "brownout" as confirmed only when your utility or the operator says so. There is no single national public source for these.
Planned and preventive shutoffs
Utilities schedule some interruptions for repairs. In some areas they also turn off lines ahead of dangerous fire weather, often called a public safety power shutoff. A warning or schedule is not the same as an outage that is happening now.
Weather alerts
The National Weather Service issues watches, warnings and advisories. A warning is about the weather, not an outage prediction. A Red Flag Warning means fire weather conditions; it does not mean a wildfire is burning.
Long-term hazards
FEMA and USGS publish long-term hazard information, such as flood or earthquake risk for a community. These describe risk over many years, not what will happen this week, and they are not a forecast for your home.
Future adequacy headlines
Reports such as NERC's seasonal and ten-year assessments ask whether a region may have enough supply under certain conditions. They describe possible risk across a large region, not the chance that your house loses power tonight.
Who does what
Three kinds of organizations get power to your home. They are easy to mix up.
- Your delivery utility owns the poles and wires on your street. It runs the outage map, takes outage reports and restores service. It may be a large company, a city-owned utility or a rural cooperative.
- Your electricity supplier sells you the electricity itself. In many places this is the same company as your delivery utility. In states with retail choice, it may be a different company. A separate supplier does not fix outages. Call your delivery utility.
- Regional grid operators keep supply and demand in balance across large areas, often several states. Some are independent system operators or regional transmission organizations (ISOs and RTOs). Every area also has a balancing authority. They issue strain notices and conservation appeals. They do not run your street's outage map.
The borders of these areas do not line up with each other or with state lines. One state can have dozens of utilities, and one operator can cover parts of many states.
How to read an outage map
It only covers one utility
A utility's outage map shows that utility's own service area. If a city-owned utility or a cooperative serves the next town, its outages will not appear there. A map shaped like your state is not proof that every utility in the state is included.
"Customers" are accounts, not people
Outage counts are usually "customers," meaning accounts or meters. One customer can be a single apartment, a house with five people, a store or a hospital. A customer count tells you how many accounts are affected, not how many people.
"No outages shown" is not "no outages"
An empty map can mean several things:
- The utility has not received or confirmed a report yet.
- The map has not updated recently. Check its "last updated" time.
- Small outages are hidden. Some maps leave out areas with only a few customers out, or brief flickers.
- The map, or the system feeding it, is not working.
If your power is out, report it to your utility even if the map looks empty. Do not assume someone else has. Restoration estimates on these maps are the utility's best guess and can change.
Cyber headlines: what is known and not known
Stories about hackers and the grid are hard to judge.
- A published vulnerability in a type of equipment does not prove that a specific utility uses that equipment, or that its systems are exposed.
- A vulnerability is not proof of an attack. An attack is not proof of an outage.
- An outage that happens during cyber news was not necessarily caused by it.
- A cause is confirmed when a named utility, regulator or government agency says so publicly. Early reports are often corrected.
Power Grid Watch does not rate utilities for cyber risk and will not link an outage to cyber activity without an official source that says so.
Official sources to go further
- EIA Hourly Electric Grid Monitor (EIA-930)FederalDemand, generation and power flows for balancing authorities in the Lower 48 states, with delays from about an hour to days. Not customer outages.
- DOE-417 electric emergency and disturbance reportsFederalSignificant incidents that grid organizations must report to the Department of Energy. Not every outage, and some reported events cut no one's power.
- National Weather ServiceFederalOfficial watches, warnings and advisories for your location.
- NERC reliability assessmentsIndustry regulatorSeasonal and long-term reports on regional supply. Check the date and season of any report you read.
- CISA Known Exploited Vulnerabilities catalogFederalVulnerabilities with evidence of exploitation. It does not say which organizations are affected.
See also Reliability and Sources and coverage.