On Wed, 27 Sep 2017, Jean-Francois Mezei wrote:
After a week without power, all the stationary batteries throughout the
telecommunications network are likely completely drained.
from the point of view of cell sites, wouldn't battery autonomy be
measured in hours rather than days? I could see some site having
autonomy in days due to permanent generator, and when fuel runs out so
does the cell site.
Yes, long-term power is generators. But there is always a catch.
What happens during disaster recovery is the batteries are damaged by
being drained repeatedly, dirty power from generators, and enviromental
conditions. After too many deep-discharge cycles during the disaster, the
batteries won't hold a charge any more. The battery failure rate,
requiring replacement, goes through the roof after about a week in a
disaster. Even those 10-year telco batteries don't last 10-years during
disaster conditions.
Since a lot of telecommunications gear actually runs off -48 volt battery
string, and the generators recharge the batteries; when the batteries
completely fail even with a generator, no more telecom. You have to
replace the battery string or run the telecom gear on raw generator power
(which then damages the telecom gear even more).
Sometimes even the battery starter on the generator fail to start after
too many refueling stops. Most backup generators are only rated for
"stand-by" service, not continuous operation for weeks. Generators need
more maintenance, and fail more often.
Disaster logistics is a string of dominos. If they start being knocked
over, it just gets worse. Stuff that works great during normal
conditions doesn't anymore. Simple fixes are all complicated now.
