Currently 20kva of power needs to be run to an outbuilding about 4000 feet away. To keep wiring practical the voltage will be stepped up at the main building, run via underground conduit, and then stepped back down. My question is it is possible to use 1000 volts between the two buildings instead of 600 volts and if so how would one go about doing it? I want to keep VD no more then 3% across this run.
'k, but there is an issue with some jurisdictions that are holding feeders to 2% now.
california is, as part of their glowing title 24 kool aid. have a sip, it's only a little bitter.
3% is a reasonable drop, assuming electrons still flow where reason exists.
bump it from 240 3ph to 575 3ph. someone will wind you a transformer, for enough money.
if it was me, i'd do three phase 208 volt wye ~ 575 delta on both ends. your 20kva will work
better for your voltage drop.
20kw will come out to 35 amps single phase @ 575 volts
35 amps on 300 MCM will come out to 2.86% voltage drop
20kw will come out to 19 amps three phase @575 volts
19 amps on 3/0 will come out to 2.89% voltage drop.
12,000' of 300 aluminum will run about $20,000
16,000' of 3/0 aluminum will run abour $14,600
2 1/2" pvc will be about $5,400
3" pvc will be about $6,600
so, single phase is $26,600
three phase is $20,000
i'm betting the 3 phase transformers will be more affordable as well.
a single phase 575 xfmr is probably not even available anywhere.