SCTE 287 2023

Right-Sizing Outside Plant Power Supplies

Executive Summary

In a cable broadband provider’s effort to become more energy efficient there is an opportunity to right-size an expanding arsenal of ferroresonant power supplies and to ensure the most efficient placement of those power supplies.

By increasing efficiency in placement, providers may benefit from reductions in operational and capital expenses, reduced Scope 2 emissions through less transmission loss to inefficient transformation, and extended runtimes. This creates potentially less need to deploy portable generators which can impact Scope 1 emissions.


This operational practice defines methods for the most efficient placement of ferroresonant power supplies. Considerations are made to:

  • recognize the cost to transform power,
  • separate runtime needs for battery charging,
  • include architecture agnostic load-based power supply sizing,
  • describe thresholds for triggering new power supply additions.