Solar quote question - half cut panels vs optimisers, cherrybrook, Sydney

Hello forum members,
Appreciate your expertise and feedback on my situation.

I have received a couple of solar quotes for a 5kW system. 15 panels is about all we can fit. We have substantial shading issues as well in winter.

One quote use REC N-Peak half cut 320W panels and the other LG Neon 2 340W panels. Both quotes use a 5kW Solar Edge SE5000HD inverter and solar edge power optimisers.

My first question is is there likely to be any noticeable additional benefit of the REC ‘half cut’ panels as both have optimisers anyway to counter shading effects? Am I just paying a premium for the half cut technology with no real real world advantage?

Secondly, I have read about oversizing system capacity vs the inverter and I appreciate undersizing the inverter isnt going to allow for future expansion but aside from that, is it just about cost-effectiveness or also about output efficiency? My roof pitch is neither ideal for summer or winter and I have read that I will lose about 10-15% capacity because of that. So for a 5kW rated system, my max possible output will be less than about 4.5kW straight up. With shading issue as well, am I wasting money paying for a 5kW inverter then?

Thanks

Hi @wizardryinc

In my opinion if you are being quoted a similar amount for both systems, you are clearly better off with the LG Neons. They are very good panels, and will give you 300W more total.

I’m not super confident on the inverter size question. My initial thought was that you would be totally fine with a 4kW, especially as they usually take an input of 4400W. But if you go the LGs you’ve got a potential output of 5100W, when you get optimal sun, you don’t want to be cutting off any of your production. Inverters are more efficient when they have a higher input voltage (so if closer to their nominal input basically), but I’m not sure that would outweigh you maybe cutting off your production. It would really depend on the exact configuration of your roof etc, but I’d say maybe go the 5kW inverter.

Cheers
Marty