Fuel cells as backup power for digital loop carrier systems

Batteries have been used as the backup power source of choice for outside plant (OSP) sites since the early 1970´s with the advent of digital loop carrier (DLC) systems. However, batteries have acknowledged downside´s. The latest round of fuel cell research provides an alternative to battery backup. Fuel cells are now a cost-effective method for backup power production for sites requiring one to three kilowatts. There has been growing interest over the past few years by infrastructure operators in finding an alternative to batteries for back up power. Batteries have been used as the backup power source of choice for outside plant (OSP) sites since the early 1970´s with the advent of the digital loop carrier (DLC) systems due to their scalability. However, companies have learned through real-world experience that batteries have some downsides, which until now have been unavoidable. The latest round of fuel cell research brings an alternative to battery backup. With fuel cells´ lower life-cycle costs, cleaner operations, longer runtimes, and lower maintenance requirements, telecommunications companies are moving to replace batteries as they reach the end of their useful lives. This paper will discuss the history and current configuration of both digital loop carriers and fuel cells. It will then outline a cost-effective proposal for use of fuel cells as back up power for DLC systems.