opinion between two panels please

[mtfalk64]

I can get SUN Thin Film CdTe 24inch x 48inch, 70 watt 34 volt VMP, 2.08 amp IMP at $0.50 a watt or $35.00 a panel or looking at SUN 235w 39inch x 65inch, 235 watt, 29.94 volt VMP, 7.85 amp IMP at $0.79 a watt or $185 a panel.  I have seen that most say watts is watts, the savings would be very good on the SUN 70 watt but it takes up a lot more area for slightly less watts of the SUN 235.  either 30 of the SUN 70 watt ($1050.00) taking up 240 sqft of area or 10 of the SUN 235 watt ($1856.00) taking up 176 sqft of area.  any input for everyone would be wonderful.

Thanks Mike

Current system
Midnite 150
16 - 6 volt 220 amp connected in 24volt series
10 - 220 watt evergreen 12v 11a panels connected in 24volt
1 - 2300 watt power bright 24v inverter (backup)
1 - 1800 watt power bright 24v inverter

[Vic]

Well,  watts may be watts,  but trying to use smaller PVs can be fairly expensive,  when racking  and wire runs/breakers/combiners are also considered.  The Thin Films that you cited are not the worst.  Some TF PVs run a Vmp of about 100 V,  often requiring strings of ONE --  those are much worse IMHO.

One or the other PVs you mentioned may work better when CC tradeoffs are considered.  Good Luck

[dbcollen]

I have a 2kw array (40)  First Solar FS-50 CdTe thinfilms, the main problem I have with them is, whenever a bird craps on them a small area of active material in the shadow arcs internally and the arc fault trips, you can see small burned spots all over the panels. The arcs seem to be self limiting and the panel array still puts out 1250w in real world conditions. My panels are double glass as well, so I am not concerned about it catching fire, as there is very little combustible material between the sheets of glass. They are wired 2 in series for 160voc, around 97vmp into a classic 250.