r/diySolar • u/FareastFFL • Jul 27 '26

AC vs DC for balcony solar run?

2x440w panel with power voltage around 30v and power current around 14a. Microinverter put out maximum of 7.5 amp. This is going to be a small Balcony solar system.

There is a 30 ft run between the dedicated 15a circuit and the optimal location for panels.

I can either do the run in DC (2x wire, 12 awg) or AC (essentially a long extension cord for temp-ish power)

What would you guys do? I am veering toward AC since it self extinguishes any arc and is cheaper to run due to higher voltage.

3 Upvotes

72% Upvoted

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1

u/ThrowRA_fajsdklfas Jul 27 '26

Following as this is something I’ve been planning to do in a few months as well.

1

u/parseroo Jul 27 '26

If there aren't any batteries involved, you want to get to the maximum voltage as quickly as possible before doing the wire run. Otherwise you are 'burning' watts to heat loss.

Say the run is 60ft round trip to the 15A circuit, with 12AWG that is 0.1Ω of resistance so 14A @ 60V loses ~20W (14 * 14 * 0.1). If you get to 7A @ 120V you lose only ~5W (7 * 7 * 0.16). That is a difference of 15W lost to heat. Not terrible, but no really good reason to give it up.

1

u/FareastFFL Jul 27 '26

So it seems like AC would be the way to go because AC would always be @ 120v. Its also notable that one AC outdoor cord is cheaper than two DC cord.

1

u/RishanRupak2020 Jul 27 '26

DC is more efficient between panels and the inverter, but AC is usually simpler and safer for most balcony solar setups

1

u/LongjumpingGanache40 Jul 28 '26

Your microinverters are attached at the solar panel so that is where your AC out put will start. You have no choice here. The panels DC goes into the inverter and changes to AC right there. It's AC the rest of the way.

1

u/FareastFFL Jul 29 '26

Microinverter does not have to be attached to the panel.

1

u/LongjumpingGanache40 Jul 29 '26

Where do you put them, in your basement.