Aluminum Cables Instead of Copper Cables?

i assume that the reticulation design is to support a low voltage distribution.

the factors that may be considered are

1. aluminum conductor cross section (csa) capacity and voltage drop vs. that of copper.(copper cables have higher admittance than aluminum conductors and therefore smaller csa sizes may be selected for a given load)
2. the availability of the sizes in aluminium conductors for low voltage is not always available in some countries, check availability before wasting time designing and comparing unnecessarily.
3. terminations, most aluminium cables need splicing onto copper tails before terminating into circuit breakers.consider cost of terminations to be higher.
4. the fault level for the circuit must be considered especially if the load is close to the substation. from the manufacturers tables, the KA rating of the cables can be found.( aluminum conductors have a smaller Ka rating than copper cables, even though you are going to use a size larger for aluminium selection.)

ps: check other threads, i have put some info on cable size calculation guidelines, it is same for cu/al cables. ensure that you cater for inrush currents in your design.

once you have the correct sizes do comparison

i hope that the 500 kW alternator is not supporting the total load simultaneously above

best of luck

On the technical side, the wiring should be at least two gauges larger than the copper wiring that you would use. Also aluminum wire does not "flex" or bend well as compared with copper wire. Also remember that the resistance is different between the copper and aluminum so that when they are spliced together that the right compatible materials are used so that fire or melting does not occur at the junction.

For this application, I would be using copper, cheaper, and for motors up to 110kw, aluminium would be completely cost inhibiting.

CR4 doesn't address <...cost...control...>. This sort of thing is commercially sensitive and not usually found in global Engineering forums.