Thread: Ben's Garage
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Old 12-17-16, 10:58 AM   #64
stevehull
Steve Hull
 
Join Date: Dec 2012
Location: hilly, tree covered Arcadia, OK USA
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Ben,

You have enough room on your new garage roof to do an eight panel (60 cell) wide (panel width = 39 inches) install in a portrait configuration. This calculation allowed 0.5 between panels and 2 inches on the end for panel attachments to the rails. This would be with 255-265 W panels.

Two of the rows (16 panels total) would give you a ~ 3.7 kW (16*.23) with the Enphase M215 microinverters. Three rows (panel length of 65. 3") would need 17 feet from eve to ridge - and it looks like you have that space. Three rows (24 panels) would be a 5.5 kW system.

The current costs for such an Enphase M215 system are about $1.05 a watt not including wiring and other electrical conduit, ground rods, etc.

If you can pay a bit more per watt, then move up to the Enphase M250 and 280-290 watt panels. Three rows with the M250 would give you about 6.0 kW (24*.25). Costs here for a self install are about $1.15 per watt (excluding wiring stuff).

The "best' would be the Enphase S280 with 320-330 W panels - but now, the additional cost doesn't pay you off (~$1.45/watt).

A 24 panel system would be perfect and would shade your southern roof - allowing you to store the sofa up there in a temperature moderated space for "occasional" use.

Looking great!



Steve
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