Blue Alloy Wire is used to carry Blutricity. The placement rules are the same with Red Alloy Wire.
There is a small energy loss when carrying power over long distances, measured to approximately 0.01 units per wire. Keep in mind that if you want to carry a lot of power, i.e. a high current, you need to keep the resistance low as the potential difference machines create is limited. You can do this easily by adding multiple parallel wires leading to the same set of machines.
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