Power requirements are one of the downsides to a PC based SDR setup, hence the El cheapo handheld Wouxuns HTs/Walkie Talkies.

The PC based solution does have its upsides though, such as the ability to record and playback video/audio from TV/radio broadcast via terrestrial and Satellite broadcasts. In an emergency situation, the lack of power is probably the main reason normal communications infrastructure is non functioning such as landline (PSTN or POTS, ADSL Broadband, Fibre etc) and cellular access. (2.5G, 3G and 4G).

Has there been any official analysis of just what exactly has the highest failure risk for communication technical failures and what backups or additional resources can be brought to bare to resolve the communications outage ASAP. In the UK PSTN/POTS telephone exchanges can fail, underground trucking node points can catch fire or be flooded, Internet Routers can be stolen, cables can be dug up accidentally and wide area power outages can happen leading to radio/tv broadcast transmissions ceasing.

Then there is the reliability of any information resource, which will usually be driven by a human intelligence (TV and Radio journalistic standards/psychological operations, gossip and propaganda propagation) i.e. especially from National SW broadcasters.

Then there is the unrelenting information deficit that happens to todays folks (which is probably a modern phenomenon) that cannot bare to left not knowing what is going on in an emergency situation and can become highly stressed when folks are not informed as to what is happening in something as simple as a power outage let alone if their Internet has gone down and cannot carry out their gossip on Facebook for example.

Unfortunately, tuning into a HAM operator talking about his radio propagation problems in the SW AM probably wouldn't be able to satisfy the information comforter (news broadcast entertainment/gossip) required by folks today.

http://www.youtube.com/watch?v=hZGNTw1uQbU