A single fixture, using 512 channels at 60 samples per second, works out at about 30.7Kb per second, 1.8Mb per minute. A 45m session at that rate is about 82Mb of raw uncompressed data.
- recording session at the protocol level
- data compression on DMX streams
- saving to SD card
- select recording from web ui to playback
Look at this library for compression: https://github.com/atomicobject/heatshrink
APA102C use about 60mA of power per pixel at full brightness white. On strips of 144ppm that works out at about 8.64A pm, about ~10A for a 20% allowance, every 10A is about 15,- eur in power supply.