Yeah I tried to figure those values out but from the extremely limited information on Minecraft wiki you get something like 0.5 - 1 day duration with 0.5 - 7.5 day pause between rainstorms. Assuming it follows a normal distribution: 0.75day/4.75days (delay+duration) = 15.8% uptime on rain. Minecraft wiki also gives a figure for the rate of lightning strikes 1/100000 / tick / chunk. Problem is there’s no figure that I could find for how often rain becomes thunderstorm… However I also don’t know how the lightning rod itself works, does it check for lightning within a certain amount of blocks? If that’s thecase how does it work in rain at supposed 10% efficiency?
Assuming something like 10% of rainstorms are thunderstorms (conservative guess I think) there will be thunder once every 66 Minecraft days or every 22hours, and assuming the rod checks 1 chunk for 0.75 days (18000 ticks) we get 500mil EU every 121 hours or 57EU/t. In the case where 50% of rainstorms are thunderstorms we get 285 EU/t. In any case depends heavily on the mechanics of the lightning rod. (All assuming it just checks its own chunk for lightning strikes)
Can you tell me what calculations the rod performs ?