Originally Posted by daniel.kusy
I completely agree with you on the fact that with data enabled on a poor 3G connection, your battery's gonna drain pretty quickly. After doing more research I found that changing from 3G to 2G can reduce power usage of the radio quite considerably (apparently up to 50% when in voice/sms mode only). Now as great as that all sounds, that's only around 50% power usage of the radio and I have no idea how much battery the radio actually uses during idle.. Looking at google's specifications it seems like the radio uses a pretty insignificant amount of battery when in idle (300 hours or so) so a 50% saving in idle radio probably wouldn't make nearly as much difference as say a more contributing factor to battery drain like screen on time or cpu usage. So yeah, I guess I gotta agree with kj2112 here, It's pretty negligible in the grand scheme of things if you're actually using your phone with wifi connected.
Interesting source if anyone was curious and wanted to learn more about radio affecting battery life: http://www.speedguide.net/faq_in_q.php?qid=362
If it did make a big difference on WiFi....I'd have terrible battery life at home. There is no 2g on my carrier and my signal at home is horrible. But, I get over 24 hours and 6 plus screen hours always, whether at home (on WiFi always...and usually one bar of radio inside) or at work on LTE.
So for me, the weak signal does next to nothing to my battery.....while on WiFi. WiFi off, I get half those times at home.
Sent from my N5, N7, Moto X, G Tab 3 or S2.....