Through this whole thing I've heard nothing about lightning which means to me you are all very far from the answer... Second thought. How does the earth store the massive amount of lightning it receives? Iron, salt, argon, boron, hydrogen, helium maybe?
Q=CV where Q is the charge in Coulombs, C is the capacitance in Farads and V is the voltage in, er, Volts. Being lazy I'm going to guess the capacitance at < <1 pF so you are in the (edited) teravolt range. I might get round to working out the capacitance of a relevant 'something' unless someone else does it first. Edit2 from https://en.wikipedia.org/wiki/Capacitance This might be the capacitance we want - if it is then 0.15 coulombs looks like about 6 billion volts which would be a bit hairy to handle.