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At JEA, we take power quality and reliability very seriously. Here are some examples of work we are doing to provide our customers with the highest quality and most reliable electric service.
Buried Cable Replacement
 Similar to the buried cable at substation exits, we have buried cable in other parts of our system. While the higher electrical load at the substation exit makes it the most vulnerable part of a buried cable, faults from moisture or cable damage can occur in any cable which is buried directly in the ground. We no longer bury cable directly in the ground. The new cable is placed inside conduit, which provides greater protection and longevity. Cable in conduit is also faster to replace, with less property disturbance. In FY02, JEA installed 105 miles of new cable. In FY03, JEA will spend 8 million dollars in cable replacements. New trenchless technology, such as directional drilling, have enabled JEA to perform these tasks with minimal disruptions of customer lawns, sidewalks, driveways and roads. The average total cost is $18.75 per foot.
Tree Trimming
Four years ago JEA examined the statistics of tree growth in Jacksonville and the practices of other utilities for tree trimming. We determined that the best tree trimming practice is a three year cycle as the routine, with hot spot trimming as needed. We began the rotation of trimming by circuit in 1998 and last year we completed all circuits, so now the process starts over. JEA continues to monitor the effectiveness of the three year cycle. In addition, we use our internal data to determine when a circuit is having an increase in tree related events and take immediate action, called hot spot trimming. An effective tree trimming plan provides more reliable service for our customers. Eighty trucks are involved in the tree trimming effort.
Wood Pole Replacement or Repair
As part of JEA's ongoing inspection of our system, we found 101 wood poles on our 69 kv transmission lines had defects. These defects would eventually result in unplanned outages on the transmission grid. These poles were evaluated for repair versus replacement. In one third of the cases the poles were able to be repaired. The rest have been replaced. The best part of the story is the cycle time reduction. Through a change in our process, once we identify a defective pole, the replacement can be done in just a few days, which decreases the likelihood of an unplanned outage due to pole failure.
Infrared Camera
 JEA is using these sophisticated cameras to help us
identify places where our electrical distribution system where preventative maintenance is required. One of these types of cameras uses infrared
thermography to scan electric connections to locate trouble spots prior to a failure. Loose connections, hot switches, load imbalance and moisture can lead to deterioration, fatigue and /or corrosion. Once identified by the camera, the replacement of these parts is then prioritized and scheduled, preventing costly equipment breakdowns and power outages. The hot spot in the picture to the right is indicated by SP01. Once identified, the temperature scale provides an indication of the severity of the problem. This trouble spot was prioritized and fixed before any customers lost power.
 Corona Camera
This year JEA has begun to use another type of
camera, called a corona camera to evaluate insulators for impurities not visible to the eye. These impurities can cause flashovers or arcing of one phase into another phase. If impurities are seen with the corona camera, the insulator is washed and re-checked with the camera, to verify the washing removed the impurities. The picture to the right illustrates a corona or "halo" effect around a dirty insulator.
Distribution Automation System
JEA is expanding its Distribution Automation System which helps to minimize the number of customers who are affected by an outage.
Transformer Inspection Program
JEA has instituted a new systematic inspection program for our larger transformers which will help to eliminate problems before they can cause an outage.
Continual Improvement
JEA is continually researching the latest technology in order to improve our reliability. Last year the total number of minutes of outages of our system declined significantly over previous years. This year you will see continued improvements in the reliability of your service, because we have made it our focus.
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