Powering a chain of 5volt sensors across 25 meters
That is only 5 amps. A 0.1 ohm piece of wire, assuming a uniform distribution of current has an average load of 2.5 amps ( and this is a linear system), will have only 0.25 volts drop.

Pick a wire size that had 0.05 ohms over 25 meters, and the worst case drop, at the far end, is only 0.125 volts which is well within tolerance of embedded systems VDD. 

Standard house wire --- AWG 12 ---- has 1.6 ohms per thousand feet or 300 meters.
Or 0.16 ohms per 30 meters. At 50 degree. Simply set the system VDD 0.2 volts high.
Or 0.4 volts, because the Ground wires will have the same IR drop.

Thus get thee to a hardware store and buy a small roll of standard SOLID 12 gauge wire.

Remember your GROUND voltages will differ, by 0.2 volts, along the distance.