Rpi uses 25watts? My old acer 6th gen laptop has a 15watt TDP and remains around 8watts 24/7 even with my services and without disconnecting the internals. My 8th gen laptop pulls 6watts with the screen on. People here saying older laptops arent a good choice are insane considering the ~$100-300 diffrence between an ewaste laptop and dedicated minipc + backup power bank (laptops have internal batterys you can easily replace when they go bad)