What will happen if we establish a physical connection between ground and ionosphere? https://en.wikipedia.org/wiki/Ionosphere 
The ionosphere is a shell of electrons and electrically charged atoms and molecules that surrounds the Earth, stretching from a height of about 50 km (31 mi) to more than 1,000 km (620 mi)
On the other hand.
https://en.wikipedia.org/wiki/Ground_(electricity)
A "ground" is usually idealized as an infinite source or sink for charge, which can absorb an unlimited amount of current without changing its potential.
And We also Know that balloon named BU60-1 has attained highest altitude of 53.0 km (53 Km means it entered the ionosphere)
So, I am wondering if may be someday we should try this. Even is that possible to connect ground and ionosphere. 
By the way, I love to think about something that is completely bizarre. Besides this I can understand problems in doing so like; Weight, material, amount of charges (if able to establish) and various others (honestly, at the moment I don't remember/know). Well, my choice of material for path is very non-conducting type such ordinary thread or anything else that is not much expensive.
I have started wondering already.
If you don't want to be specific, that is great but please don't involve too much mathematics in explanation (if there is one!). Answer in such a way that everyone understand and make them love science and specially Physics.
 A: @CuriousOne is approximately right. Others have thought of it, the url below is a paper from one who concludes with slightly more careful calculations (but still relatively straightforward) that the most one could get in terms of a continuous power from it is 50 MW, and typically a lot less. 50 MW is 5% of a large power plant. 
http://www.electrostatics.org/images/a2.pdf 
The paper uses 200KV instead of 300, but both are in the right ballpark. The paper figures out the most power that can be extracted from an equivalent circuit diagram. It also shows how little can be extracted from local harvesting. 
An interesting intro to the the whole topic of the global atmospheric electrical circuit can be found in the url below, the first lecture in a course on it. It shows nicely the fair weather global circuit. 200-300 KV is about average, and it shows other applicable parameters.  
http://www.atmo.arizona.edu/students/courselinks/spring13/atmo589/ATMO489_online/lecture_1/lect1_global_elec_circuit.html
