More panels, voltage drop, wire runs

[qrper]

Well I managed to get up another 2kW of PV the other day.

So, now the fun begins. I've been playing with an online voltage drop calculator and it seems that my 150' run (one wire) at 90V @ 50A will drop 4.14 % using 4 gauge wire. If I change the wire size to 2, the voltage drop isn't that much better at 2.6%. I'm working if The cost of the larger size wire is worth the extra 2% increase in efficiency? Even changing to 120 V only drops the percentage of loss to 3.11% The classic 150 didn't like the 120 V input, ran quite hot.

Using 6 gauge wire to save some $$$ will produce 6.85% voltage loss.

I'm up for some suggestions

I'm mike, WB8VGE

[mike90045]

Price out using aluminum wire, you need 2 gauges larger wire (instead of #2, need #0) but it's less expensive. 
You may need copper/aluminum rated interconnects.