How to calculate the power pool?

[otho]

Can someone please tell me how the power pool is calculated. Being a Midgard I assume it is Piety x "Mythicspecialformulanottobeknownbymortals" + pow from items. I be happy if some got some information about this that is backed up in some way with data or "Mythic quotes".

 

[Arnor]

cast a spell X times till your oop, multiply X with pow cost. Its not exact but wth should you need to be exact?

 

[old.Trine Aquavit]

I'm pretty sure it's calculated as:

Base power + casting stat + power

A point of casting stat has the same effect as a poit of power for a non cloth caster (for cloth casters the casting stat also effects damage caps).

 

[Zebolt]

How much is base power then?