May be of interest, posted on the Startups of Puerto Rico Slack channel earlier today:

Marcos Cruz [4:41 AM]
I hope everyone is well, Noob question: Does anyone know for how long do the power plants of cell towers run on diesel?

Mike Rosado:house_with_garden: [8:03 AM]
I spoke with my parents in Carolina, and they have been without power since 4am
[8:03 AM]
Sprint towers are down, but AT&T towers are running.

Mike Rosado:house_with_garden: [8:23 AM]
I'm part of the volunteer team at the ITDRC and I am on the ITDRC Slack channel.
We already have many volunteers in Puerto Rico. Should you need communications help, please send me a private message, and I'll forward it to them. https://itdrc.org/ (edited) 

M Pilar  [9:24 AM]
~24h in urban zones ~48h in other zones, but if they are large towers they also have batteries that last 1-8h

Ariel Zavala [9:32 AM]
What ISPs are up right now?

Mike Rosado:house_with_garden:  [9:39 AM]
Right now Liberty and WorldNet are being brought up.
:+1:1

Mike Rosado:house_with_garden:  [9:41 AM]
Liberty in some places and not others, after that they return to ATT LTE

Matt Van  [10:35 AM]
Optico is up
:heavy_check_mark:2

Tomas Irizarry [10:48 AM]
@mikerostx dude ITDRC sounds super interesting. Do you know if there is anything like a mobile datacenter where a community could set up a WAN for services/communication?

Tomas Irizarry [10:48 AM]
in the event private networks are down

Mike Rosado:house_with_garden: [10:53 AM]
replied to a thread:
@mikerostx dude ITDRC sounds super interesting. Do you know if there is anything like a mobile datacenter where a community could set up a WAN for services/communication?
We (ITDRC) have volunteers with boots on the ground in Puerto Rico. @Ruth Silva is one of a dozen or more people there working on these efforts.

Tomas Irizarry [10:55 AM]
Thats amazing. I dont know what I can contribute but I’ll join and see where I can . (edited) 

Mike Rosado:house_with_garden: [10:57 AM]
Always plenty of ways to contribute and have corporations volunteer their employees to help those in need. :wink:

Tomas Irizarry [10:57 AM]
actually..
[10:57 AM]
now that you bring that up
[10:58 AM]
we’re actually in the middle of deciding what non-profits to disburse our donation fund to
[10:58 AM]
let me check what the process is and I’ll put in ITDRC for discussion

Mike Rosado:house_with_garden: [10:59 AM]
When Maria hit :flag-pr: , I was deployed for several weeks to help out. Trust me, there's plenty to contribute and do. :wink: