Looks like butcher table is bugged as other structures require much less materials (less than 1.7?).
But surprisingly raw mushrooms are able to feed my 5 colonists, anyway I'd better start butchering dead raiders to get leather.
Comm console require 0 power. So on one hand it doesn't work without power source. On other it's possible to charge battery a bit and then turn off power station.
Upd. Strange costs again. Heater: 5 steel parts, 2 spare parts, 1 mechanism. Small heater: 8 steel parts, 3 spare parts, 1 mechanism.