making mppt solar controller with ardrino and making it upgradeable

[npicot2304]

Hi all

now i am currently in the process of making my own 12v solar charging station for my shed (lighting inside and outside at this stage), the only thing i am missing at this present stage is the charge controller as i don't really want to buy one of those cheap Chinese controllers that say they are MPPT but are not and in fact PWM as i am sort of pushing the boundary's of battery capacity. so after doing a bit of reading on a few websites including instructables i seen that someone had created a MPPT solar controller using the arduino uno but the system could only handle 50w max so what i am wondering is, is there anyway that i can make it handle more current then that or am i waisting my time by trying to create it

here is the website that i have been looking at
http://www.instructables.com/id/ARDUINO-SOLAR-CHARGE-CONTROLLER-Version-30/

the other thing is that the reason i went with the arduino MPPT solar controller is i want to be able to upgrade it when i needed as well as learn a lot more about microcontrollers.......

hope i have put this in the right section