The display console unit can run on batteries only. However, without the a/c power cable, the display only stays on for seven seconds, and to get the display to come on, one has to press a button on the display console. Also, when running on batteries only, the unit will not maintain a wifi connection, so it won't reliably upload weather data to WeatherUnderground or other weather networks. 

You can put it on a pole. Mine is on a 30ft pole. It works really great. Just make sure that it is not around a lot of trees. It can change some of the sensors like the wind speed and direction. And I found the first pole I had it on. In the wind, the pole wobble a little. So it effected the wind speed a little bit. So I used a little sturdier Pole and guide wire it. It did the trick. 

Simple, u turn the plastic bracket around, fit the sq plastic in the other way, then get a wall bracket and pipe and mount your unit on the pie and finally on the wall 

Mine reset itself the next day, I didn't do anything to initiate it. 

Yes, you can view it online. Once I setup the WiFi connection and registered my Sainlogic weather station with Weather Cloud, it appears on the WC web site with the current data from my station. 

It just shows gusts and average, but when the gust stays the same that pretty much is current wind. 

Yes. You can connect to Weather Underground and then share out your station info.