Power Flickers

Flickers may occur at any time – even on a sunny day – and can be caused by a number of factors, including:

• Lightning strikes (Florida is the lightning capital of the nation)
• Damaged electrical equipment
• Vegetation – tree branches, palm fronds or other debris – making contact with power lines
• Animals interfering with electrical equipment
• Salt spray affecting FPL equipment in coastal areas

Let's look at one example using the illustration below. One of the most common causes of power flickers is when a tree branch or palm frond is blown into overhead power lines. When the branch makes contact with our lines (A), the system detects the interference and shuts off electricity to that section of the line for a brief period – usually a few seconds (B). The tree branch or palm frond typically falls to the ground, allowing service to be restored quickly.

This process allows the system to determine if there is a break in the line or other electrical difficulty. Briefly shutting off power and isolating the problem area helps prevent damage to the electric system, which could result in a longer outage and affect many more customers.

For example, a flicker on your local power line could affect electric service for you and 200 of your neighbors. Without this brief interruption, the outage could last several hours, spread to other power lines and affect service for thousands of customers.

In addition to affecting customers served directly by the affected power line, other customers in the area who receive electric service from adjacent lines may also experience a flicker. Interference on the line, such as a fallen tree branch, often produces a brief drop in electricity – called a “voltage sag” – on adjacent power lines that affects customers served by those wires.

Conversely, a lightning strike could cause a power “surge” – a brief, but noticeable increase in electricity in your home or business that may cause a flicker.

You may notice the lights flicker or experience a brief outage lasting several seconds. There also could be a series of flickers over a period of a few minutes. Although these outages are brief, we understand how frustrating they can be for you. Your appliances and electronic devices may shut off and need to be reset.

In years past, the impact was minor, perhaps resulting in a flashing digital clock. But today, many of the items now common in homes and businesses – computers, microwave ovens, TVs, DVRs and more – are highly sensitive to changes in electricity flow. Resetting them can be both frustrating and time-consuming.

Power flickers can even affect your service if you receive electricity from an underground power line. Underground wires ultimately connect with overhead lines and equipment located elsewhere on the power grid, away from your immediate area. Animals and reptiles also sometimes interfere with underground power cables.

FPL is further researching the causes of power flickers to determine their full impact on customers. More importantly, we're identifying and taking steps to reduce their number.

Advanced technologies – including smart meters – are helping us better understand what our customers experience when flickers occur. We’ve conducted an extensive analysis, and it’s apparent there is no single solution to reducing their frequency.

That's why FPL is working aggressively on several fronts to achieve near- and longer-term results, including:

• Targeting power lines that experience the highest number of flickers for improvements, including equipment upgrades and new technology
• Investigating and testing a number of new cutting-edge technologies, including those designed to prevent problems caused by lightning and salt spray
• Clearing vegetation from 15,000 miles of power lines annually
• Adding new safeguards to discourage interference from animals and birds

As we focus on reducing flickers, you can take steps to minimize their effect on your home or business. Devices such as uninterruptible power supplies (UPS) and surge protectors can help maintain the flow of electricity and prevent possible damage to your appliances and equipment. Surge protectors act like electrical sponges, absorbing excess energy and preventing most of it from reaching your electronic devices.

See our Guide to Power Outages for more information.

At FPL, we understand how frustrating power outages, or flickers, can be – and we’re committed to reducing them and their impact on you. Here are the most common questions we receive from our customers. See our fact sheet, Reducing Power Flickers, for additional information.

What causes power flickers?
There are several factors that can trigger power flickers: lightning, damaged electrical equipment, and objects making contact with power lines, including tree branches, palm fronds and vegetation – even animals. In coastal areas, salt spray from the ocean can affect FPL equipment and cause flickers at your home or business.

Why do they occur in good weather – even on a sunny day?
While power flickers are more common during stormy or windy conditions, they can occur at any time and in any weather. The causes of flickers – animals and vegetation making contact with power lines, lightning and other factors – never take a rest.

Why are homes and businesses served by an underground power line affected by flickers?
Even if you receive electric service from underground power lines, you may be affected by brief outages because the underground wires ultimately connect with overhead lines and equipment – including power substations – that may be located away from your neighborhood. In addition, animals and reptiles sometimes interfere with our underground power cables, causing flickers or longer outages.

Why do these brief outages seem to occur frequently in some neighborhoods?
Power flickers can be caused by a number of factors (see above). If you are experiencing flickers or longer outages, please contact us at 1-800-4OUTAGE (1-800-468-8243) and we’ll work to improve your service.

Can power flickers damage home appliances or other electronic devices?
Any appliance or device that plugs into an electrical outlet can be affected by a disturbance in the flow of electricity into your home or business. More sophisticated equipment, such as computers, DVRs and satellite TVs, typically are the most sensitive to changes in electricity. There are several steps you can take to prevent problems when a flicker occurs. See our Guide to Power Outages brochure for extensive information on preventing, investigating and fixing power problems.

What is FPL doing to prevent these brief power outages?
Power flickers are a growing concern among electric utilities nationwide, and FPL has mounted a major effort to minimize them and their impact on you. We’re analyzing the cause of these brief power outages and testing new methods – including cutting-edge technologies – to alleviate them. It’s apparent there is no single solution to power flickers, and no technology or process currently exists to eliminate them. However, we’re taking action on a number of fronts as part of our commitment to reduce power flickers throughout our electric system.

Is there anything customers can do to protect their electronic devices?
Yes. Readily available “uninterruptible power supplies” (UPS) and surge protectors can help stabilize the flow of electricity and prevent damage to your appliances and equipment. See our Guide to Power Outages brochure for more information about how to troubleshoot issues and protect your equipment.

Where should customers call to report power flickers?
You can report a power outage – whether it lasts a few seconds or longer – by contacting us at 1-800-4OUTAGE(1-800-468-8243) or reporting the outage online.