How do you power them? Via the battery? I was thinking about turning my old mbp into a build machine, but i am a bit concerned with running it via the battery 24/7
Most old PC laptops have external batteries you can detach by pulling out on a springloaded tab. Even MacBooks are possible to run without the battery, but it requires some NVRAM trickery IIRC.
Maybe put it on a timer, or have the laptop control its own outlet.
I usually disconnect the battery and just power them via USB-C. The battery on these old broken laptops is usually toast anyway...