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+A full 24 hour cycle is 16*24 ticks = 384 ticks, which is about 6-7 minutes, depending on the game server configuration. The sun intensity varies during the day and peaks at about 12h00, the equation of for the sun intensity is `f(x) = -0.25 x² + 6x - 27` rounded to the nearest integer with a floor of 1. 
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+![Sun intensity](https://user-images.githubusercontent.com/7120851/34342393-bfa33cfc-e97c-11e7-8e8b-b443af68bb3b.png)
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+All Cubots are equipped with a small solar panel that charges the internal battery at the rate of `<Sun intensity> * <Solar panel multiplier> kJ` per tick. As of v1.3a, the Solar panel multiplier is 1.
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