Electric Reliability

Many of our customers are curious as to how FPUA compares to other utilities with regard to reliabilty. 

How Does Fort Pierce Utilities Compare to Florida Power & Light?

Reliability is an aspect of utilities that many of us don’t appreciate until it starts failing. Not only do outages cause an inconvenience to residents, it can also affect the profitability of businesses that rely on utilities to maintain production or services.

Reliability of electric systems is gauged using several criteria adopted by the industry that, in general terms, measures the length and frequency of power outages.

The System Average Interruption Duration Index (SAIDI) measures the average duration of interruptions for the average customer. For the last 3 years, including the 2004 hurricane season, FPUA’s length of outages was significantly shorter than FPL’s (Figure 1). As an example, our SAIDI in 2006 was 21.74 compared to FPL’s 74.3.

 

 

 

 

 

 

 

 

 

Figure 1 – The System Average Interruption Duration Index (SADI) indicates the duration of an electric outage. The goal is to have the lowest score possible which means that the outage is short in duration.

The Customer Average Interruption Duration Index (CAIDI) measures the average repair time experienced by the average customer who experiences an interruption (Figure 2). Again, FPUA’s reliability fares much better thank FPL’s. In 2006, our CAIDI was 45.67 compared to FPL’s 57.8. In addition to the electric side, FPUA’s water and sewer customers experience very few system outages.

 

 

 

 

 

 

 

 

 

 

Figure 2 - The Customer Average Interruption Duration Index indicates length of interruptions for repairs. The goal is to have the lowest score possible which means that the outage is short in duration.

Another gauge that is used to measure electric reliability is the LBar. The LBar measures the average length of time of single service interruptions. The length of time that customers must endure for power outages is far shorter for an FPUA customer compared to FPL (Figure 3).

 

 

 

 

 

 

 

 

Figure 3 - The LBar measures the average length of time that customers endure
for power outages. The goal is to have the lowest score possible which means
that the outage is short in duration.

The System Average Interruption Frequency Index (SAFI) measures the average frequency of interruptions for the average customer. For the last three years, FPUA has tremendously improved the frequency of power interruptions and in 2006 was four times better than FPL (Figure4).

 

 

 

 

 

 

 

 

Figure 4 - The System Average Interruption Frequency Index measures the average frequency of interruptions for the average customer. The goal is to have the lowest score possible which means that there are fewer interruptions per
customer.

The Momentary Average Interruption event Frequency Index (MAIFIe) measures
the average momentary interruption events per average customer. For the last
three years, FPUA’s customers experienced fewer momentary power
interruptions compared to FPL (Figure 5).


























Figure 5 - The Momentary Average Interruption event Frequency Index (MAIFIe) measures the average momentary interruption events per average customer. The goal is to have the lowest score possible, which means that there are fewer momentary interruptions per customer.