What is the watt draw from the modem? This is 450 watts and if the modem draws 40 watts, you have several hours before it goes out on you.
That being said, the modem can be powered, but any electrical equipment to drive the signal from the provider to you might be out thus making it useless. If I have a power failure, my Rogers modem will be running, but the TAP outside my house does not have any power going to their broadcast amp so still no signal.
Selling your Used Vehicle, Returning your Leased Vehicle, or Shopping for a New Car? Here are some Tips and Tricks
My Cell Phone Providers: Koodo Mobile and Zoomer Wireless