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Hurricane Ian Highlights Electric Utility’s Outdated Reliability Metrics

At the end of September and beginning of October, 2022, Hurricane Ian hit the southeastern United States, prompting mandatory evacuations across Florida and causing massive damage in Florida, Puerto Rico, and several other states. This severe storm left millions without power for several days after it had passed. On Tuesday, October 4, five days after Hurricane Ian initially hit Florida, almost 400,000 homes and businesses remained without power.

In the wake of Hurricane Ian, Florida Power and Light led an electric power restoration effort based on historic standard solutions: a restoration workforce of almost 21,000, including people from over 30 states, worked round the clock to restore power to customers that were able to receive it. Additionally, nearly 40 staging areas were established to help stage and process equipment. The utility expected that 95% of customers would have power restored by Friday, October 7; this number excludes buildings that could not safely have electric power restored, such as severely damaged homes, or homes in heavily flooded areas.

Though the days-long outage will negatively impact Florida Power and Light’s reliability metrics like SAIDI and SAIFI, these metrics are relatively meaningless to customers experiencing outages. Furthermore, the national news coverage showed the entire country exactly how widespread the outages were. Some reports were confusing because of the lack of understandable metrics.

Much of this confusion is due to outdated reliability metrics, which are designed to serve electric utility managers and regulators. By creating new, updated, customer-focused reliability metrics, electric utilities can avoid the confusion and distrust that customers often feel towards them after a severe storm causes widespread outages. Better metrics will also allow the media to present more accurate reports of current outages and restoration timelines.

Furthermore, updated reliability metrics will be essential for severe weather recovery efforts, especially as homes and businesses go all-electric, and electric vehicle adoption becomes more widespread. Let’s take a closer look at how updated customer reliability metrics will help electric utilities update to the fourth generation (4Ge) electric power grid.

Outdated Reliability Metrics Are Irrelevant to Customers

SAIDI (System Average Interruption Duration Index) and SAIFI (System Average Interruption Frequency Index) are two commonly used reliability metrics within the electric utility world. These traditional metrics are useful for individual electric utilities when analyzing year over year trends. They have some value when comparing electric utilities within a region.

However, these metrics are not helpful to customers experiencing an outage. Due of their technical nature, SAIDI and SAIFI are irrelevant to the media and are rarely referenced in reports on outages and restoration efforts after a severe weather event. Additionally, traditional metrics have little value when comparing electric utilities across the United States; for example, SAIDI metrics in Florida are irrelevant to utilities in Oregon because the climate and weather in these regions differ greatly.

Update Metrics to Improve Customer Satisfaction

While historic metrics (SAIDI, SAIFI) can continue to exist within electric utilities for internal reporting, utilities would greatly benefit from creating new, customer-focused reliability metrics. These would be far more relevant for customers to refer to as they try to gauge the restoration of electric power to their homes and businesses after a severe weather event. Additionally, updated metrics would provide a consistent point of comparison for national media coverage of severe weather related outages.

New reliability metrics may include:

  1. Long Interruption Duration (LID), which accounts for the duration of long interruptions to electric power, including days or weeks’ long interruptions due to severe weather.

  2. Multiple Interruption (MI), which tracks the number of interruptions that individual customers experience.

  3. Multiple Momentary Interruption (MMI), which reports the number of short interruptions to electric power that customers experience.

These metrics are focused on reliability for individual customers, which direct relates to customer satisfaction. As electric utilities transition to distributed renewable energy sources and consumers transition to full electrification of homes and businesses, these metrics will be important to each and every customer. Just as Google Maps provides traffic data in real time, electric utilities must develop real time customer reliability metrics, available to customers and the media via their utility’s app.

After the Storm: Electric Vehicle Charging Considerations

As electric vehicles (EVs) become more commonplace, customer expectations for availability of electric power will change. Reliability metrics that are easily accessible and understandable to customers will be key to supporting both everyday EV charging, and charging availability after a severe weather event.

When it became known that Hurricane Ian would make landfall on the western coast of Florida, 2.5 million residents evacuated to inland areas. In the future, as EVs become more prevalent, a similar evacuation order could mean that coastal residents drive approximately 250,000 EVs to inland locations. Once they have arrived at their temporary residences, owners are likely to want to immediately recharge their EVs so that they are prepared to drive home.

During the evacuation, total electric demand will be essentially unchanged, but demand will shift from coastal areas to inland areas. Each Level 3 (fast) EV charger will place a demand of 12 KW on the power grid, while each Level 1 (slow) EV charger will place a demand of 1.5 KW on the power grid. These 250,000 EVs will transfer 500 MW of load from coastal areas to inland areas with the expectation that the EVs will return to coastal areas as soon as the evacuation order is lifted.

Because of this, some inland areas will experience peak load conditions for days, until evacuation orders are lifted. In the days after evacuation orders end, customers will expect that charging stations will be available in evacuated areas so that they can return to their temporary residences each evening after completing repairs at their damaged, permanent residence.

New Metrics will Aid Recovery Efforts

Electric utilities marshal forces and prepare for recovery after hurricanes hit because they recognize that hurricanes are yearly events. In the days preceding Hurricane Ian, hundreds of vehicles and thousands of linemen and supplies traveled to Florida to prepare for recovery. To electric utilities, hurricane related EV charging is an esoteric consideration, that is, it hasn’t happened yet so utilities are not prepared.

In the future, thousands of Level 3 EV battery chargers with dedicated power supplies will need to be added to the list of hurricane recovery essentials. Drivers will expect that parking lots equipped with hundreds of Level 3 chargers will be established at numerous locations. This will be just as important as restoring power to individual households.

After a storm, electric utilities would update their new customer reliability metrics on their apps in real time to show where EV charging stations are available. The app could notify customers once EV charging stations are up and running in evacuated areas, as well as the electric energy restoration timeline for evacuated areas. By providing this data in their app, electric utilities will provide customers and the media with an accurate status of electric power available and restoration times.

Our Thoughts are with Hurricane Ian Survivors

Though electric power has been restored to much of the service area impacted by Hurricane Ian, full recovery will take months. As the recovery effort continues, we at Prescient hold hurricane survivors in Florida, Puerto Rico, and all the places impacted by Ian in our thoughts. Consider donating to the American Red Cross to help those whose lives have been changed by this severe storm.

To learn more about other updates to the electric power grid, especially as climate change fuels more severe storms like Hurricane Ian, check out our climate change blog collection, or contact us to discuss solutions.

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