By the Numbers: DA Investments Add Up

Distribution Automation (DA) technology has been active for over 25 years, but many utilities are just starting to realize the substantial benefits it delivers.

According to the Department of Energy (DOE), there are “more than 6 million miles of distribution lines in the US and more than 200,000 distribution circuits that provide the critical link to 160 million electricity customers.” Now consider that “close to 70 percent of the transmission and distribution lines are more than 25 years old,” and you see why the ability to remotely monitor and react to system events is such an important part of the smart grid.

Looking at utilities that have implemented DA, the DOE discovered:

1. DA reduced the number of customers interrupted per outage event by 55 percent and reduced customer minutes of interruption by 53 percent.
2. In one year, three utilities reported System Average Interruption Frequency Index (SAFI) improvements of 17 to 58 percent.
3. DA operations avoided more than 197,000 truck rolls and 4 million vehicle miles traveled over the course of four years.
4. Improved efficiency saved an estimated 2,350 metric tons of CO2 equivalent (the same amount produced to power 214 homes for a year)

Specific utilities have also shared positive results from automation programs:

1. Southern Company realized about 3.4 million in net present value from deferred distribution capacity investments.
2. AEP has estimated five times the ROI when DA is added to their business case as compared to AMI alone. At AEP Ohio, total benefits over a 14-year period are estimated at $1.4 billion.
3. NES implemented a demand voltage reduction project in 2012 to curtail up to 40 MW of coincident peak load, resulting in annual savings over $1 million per year.

Hundreds of man-hours can be avoided with just a 5 percent reduction in SAIDI, while Fault Location, Isolation, & Service Restoration (FLISR) can reduce the number of affected customers and average minutes of interruption by as much as 50 percent during a feeder outage.

The safety, efficiency, reliability and environmental benefits of DA are substantial and well documented. Whether adding DA to an existing AMI network, or using it to lead the business case for AMI, the numbers create a compelling case.