Got around 800 miners and around 400 furnaces and using 1.6GW. is that normal. Seems to me it is a bit to high. one iron and one copper ore mining field and both a smelting setup. some depot and a small starter base.

From my playthrough, my machines seemed to use the right amounts. Of course the power consumption is a guesstimate exactly as much as the machine crafting costs are. I counted 7 beacons on average per machine for a 12-beacon build.

Do note that even if none of the machines is working, they still have the drain, just like beacons would have. I also noticed that it's much more tempting to use the Beaconed machines on recipes that you normally wouldn't use beacons on (for example in the "mall" parts of the factory).