When the lights go out unexpectedly, how long this power outage lasts will definitely impact our lives. Well, today's post will walk you through the common causes of power failures, how to estimate outage durations, and tips to get through short and long power outages.
What Are the Causes of a Power Outage?
Power outages can occur for a variety of reasons:
- Severe Weather - One of the most prevalent causes of widespread power disruptions is destructive and hazardous weather. Storms that bring lightning, high winds, ice storms, snow storms, and other extremes can readily damage components of the electric grid. Heavy winds can topple utility poles and lines, while lightning can strike equipment and facilities. An accumulation of ice on lines and equipment becomes heavy, causing breakages. Even dense, wet snow can collapse overhead poles and disrupt infrastructure. The impact on transmission and distribution hardware from storms often results in outages across entire regions that may take days to fully repair.
- Equipment Failure - At power generation plants, substations, and along the grid, the complex components and systems that keep electricity flowing can occasionally fail. This includes transformers, voltage regulators, protective relays, conductors, insulators, and connections. Failed pieces of equipment that need replacing or repairing will cause more localized outages in the vicinity of the damage. For example, a damaged transformer may cut off power to a neighborhood until repairs are made. Equipment failures can happen independently or might also result from weather extremes overtaxing gear.
- Damage and Accidents - Power disruptions can also be caused by various forms of physical damage and accidents involving the electrical infrastructure. Car accidents and pole collisions can certainly bring down lines and poles. Excavation and dig-ins that sever underground cables are another issue. Damage can also result from tree limbs falling on lines and equipment or animals interfering with infrastructure. The extent of the damage and how vital the affected components are dictates whether the resulting outage impacts a small area or is more widespread.
- Scheduled Maintenance - While not unplanned outages, there are also power interruptions that occur for scheduled equipment maintenance, repairs, and system upgrades. Utilities have periods where they deliberately cut off service to certain areas to safely inspect, replace, or improve their infrastructure. They also conduct vegetation management like tree trimming along power line routes during particular times of year to prevent hazards. These maintenance outages are communicated to customers in advance whenever possible so they can prepare.
- Overloaded Circuits - During periods of extreme heat when electricity usage surges to run air conditioning across a region, the resulting heavy power load can overwhelm the designed capacity of utility circuits and equipment. To prevent longer disruptions from damaged infrastructure, utilities at times impose temporary rolling blackouts that intentionally cut power to blocks of customers for set time periods, like an hour or two, before rotating to other areas. This helps safely manage their overall load.
- Power Generation Shortfalls - Disruptions can also arise from an insufficient supply of electricity being generated versus customer demand across a service territory. Causes may include a lack of rainfall limiting hydroelectric output, coal or natural gas shortages, infrastructure problems at aging power plants, and other factors straining generation. When supply is insufficient, major grid operators may have no choice but to impose larger area outages to avoid a catastrophic regional blackout until additional generating capacity comes online.
In summary, power failures stem from a range of complex factors affecting the fragile electric grid network from beginning to end. But understanding the typical triggers helps estimate outage timeframes and prepare accordingly when the lights go out.
How to Know the Duration of the Power Outage?
When an unplanned power outage suddenly occurs, having a sense of how prolonged the blackout may be allows you to better prepare and manage through the disruption. While exact restoration times are impossible to pinpoint upfront, there are several techniques you can use to get a general idea of the outage scale and severity to estimate downtime:
- Check Your Utility's Outage Map - Most major electricity providers have online outage maps that show current areas impacted and will give estimated restoration times as they are known. These maps are continuously updated as damage assessments occur and repairs get underway. Outage maps should be your first stop when the lights go out.
- Call the Utility Hotline - Speaking directly with your electric company by phone can provide additional detail beyond the web maps. The customer service reps will often have the latest info from crews in the field on outage causes, the extent of damage, areas affected, and anticipated timeframes for fixing issues. They may also take down your location specifics to escalate your area.
- Look for Work Crews - If you see utility trucks, crews, and active work zones around your neighborhood, it's a sure sign that repairs are underway but likely extensive enough to take an extended time. The more crews present, the more complex the restoration.
- Assess the Outage Scale - Widespread blackouts affecting entire cities or regions generally take much longer to remedy than localized outages in a subdivision or specific part of town. The scale points to infrastructure complexity.
- Consider the Circumstances - Severe weather like hurricanes, ice storms, and heavy winds or accidents causing extensive damage to poles, lines, and substations will require lengthy repairs. More benign causes like a downed tree limb on a line may be restored quicker.
- Monitor News Alerts - Local media, especially radio and TV, will often provide live updates directly from utility spokespersons and officials on power restoration efforts, which can provide helpful time estimates.
- Look for Social Media Updates - Many electric companies also post outage statuses and updates via Twitter and Facebook which can offer real-time insight.
Synthesizing these various data points from different sources will allow you to make an educated guess on just how long your lights may stay out. While timeframes may shift, being armed with preliminary estimates helps you make appropriate preparations as you await the return of power.
How Long Does a Power Outage Last?
While every power disruption is unique, having a general sense of the estimated restoration times for different causes of outages can help you know what to expect when the electricity goes out:
- Momentary Blips - Very brief outages lasting only seconds or minutes are often caused by a tree branch temporarily brushing a power line or an animal briefly interfering with equipment. These cause a quick interruption that will automatically restore once the interference passes and equipment re-energizes.
- Minor Equipment Issues - Localized outages from minor damage to power infrastructure components like a failed transformer, downed power line, or blown circuit breaker often last 1-6 hours. In these cases, crews arrive on-site quickly for repairs or to replace damaged parts. The limited scale makes restoration reasonably fast.
- Major Equipment Damage - If large utility poles and lines are toppled, substations are damaged, or other vital infrastructure sees heavy damage, especially from severe weather, the resulting outages can persist for 24 hours or longer. The scale of destruction and complexity of repairs will dictate the timeline.
- Weather-Related Outages - Among the lengthiest power failures are those caused by hurricanes, ice storms, Derechos, and other extremes that inflict widespread destruction across utility service territories. In these cases, many homes may be without power for a week or more as grid infrastructure is gradually rebuilt.
- Rolling Blackouts - During periods of excessive power demand that stress the electric grid, utilities may impose temporary planned blackouts that rotate through blocks of customers for 1-2 hours before rotating to other blocks. This helps manage overload until demand decreases.
- Maintenance Outages - When utilities schedule infrastructure downtime for repairs, upgrades, inspections, and vegetation management, these planned power interruptions typically last between 4-8 hours before service is restored. Critical customers may receive advance notice.
- Regional Grid Blackouts - Very rarely, cascading failures across interconnected regional grids can cause prolonged multi-state blackouts lasting days, like the Northeast blackout of 2003 affecting 55 million people. But grid safeguards help prevent these larger events nowadays.
In general, minor local outages tend to last up to 6 hours at most, while severe weather incidents can create outages lasting several days. Being aware of typical timeframes by cause can set appropriate expectations.
How to Prepare for Power Outages?
Once you have an estimate of whether an outage may be short-term lasting under 6 hours or a prolonged multi-day event, you can take appropriate preparations and precautions:
For short outages:
- Unplug sensitive electronics like TVs, computers, and appliances to avoid damage from power surges when electricity is restored. Leave one lamp plugged in to know when power returns.
- Keep refrigerator and freezer doors closed as much as possible to retain cold air and keep food safe. A full freezer can maintain safe temps for up to 24 hours if doors stay closed.
- Use natural daylight from windows to light interior rooms if the outage occurs during daytime hours. At night, use battery-operated flashlights rather than candles to avoid fire hazards.
- Make sure mobile phones, tablets, and other devices are fully charged to stay connected for utility updates and to contact family if needed. Have battery packs or car chargers available too.
- Pass the time by playing traditional board games, cards, or puzzles that don't require electric power. Also, consider listening to a battery-powered radio for updates.
For long outages:
- Have extra batteries for flashlights and radios as well as battery packs to recharge phones, medical devices, and other critical electronics for at least 3 days. Also, use non-electric lanterns.
- Fill spare water jugs and pots ahead of time for drinking water and toilet flushing if municipal water service is interrupted.
- Add ice packs to your refrigerator and limit openings to retain safe food storage temps for 24-36 hours, then transfer perishable foods to coolers with fresh ice.
- Use portable power stations or solar generators rather than gasoline generators - Portable power stations provide safer, quieter power indoors without toxic fumes. Recharge solar generators by day to use at night. Just be sure to have enough capacity for essentials. Avoid noisy, gas-powered traditional generators that release deadly carbon monoxide buildup indoors. If using a gasoline generator, only operate it outdoors in an open area away from windows. Refuel the generator only after the engine has cooled to prevent fire risks.
- When safe, visit a community location with power for device charging, internet access, warmth, and hot food if your outage will last days.
- Turn off and disconnect furnaces, water heaters, and home electronics to prevent damage from a power surge when electricity is restored after an extended outage.
- If weather forecasts indicate an outage could last a week or more, consider proactively booking a hotel room that has power until service is restored.
Following appropriate tips tailored to the expected outage duration will keep your family safe and help ease the challenges until power is restored. Having emergency portable power stations available can also provide electricity for lighting, device charging, and small appliances during both short and extended outages. Portable stations serve as an essential backup power source whether you're dealing with a minor 6-hour disruption or an outage lasting multiple days when grid electricity is unavailable. When prepared with portable power, weathering outages becomes more manageable.
Power disruptions can range from brief blips lasting just minutes to extensive outages lasting a week or more. Being aware of the typical timeframes for restoration based on the cause, checking with your utility, and following sensible tips will help you get through blackouts safely. Patience and community support can go a long way when the lights go out. Maintaining emergency preparedness kits and plans will ensure you can successfully weather whatever duration outage occurs in your neighborhood.