First, here's a sketch of our somewhat "piggy", and MANDATORY, night-time electrical requirements:
CPAP, approx 8 hrs @ 60W = 480 Watt-hours
Evening Lights, etc = 3 hrs @ 60W = 180 Wh.
Bathroom visits and "etc" = 1 hr @ 100W = 100Wh.
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total mandatory: 760 + 15% power losses (inverter for CPAP, wire losses, etc.) ~ 900 Wh.
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Batteries:
At 12V, this corresponds to 75 Amp-hours. My 2619 has two group-24 battery boxes on the front (Swing Hitch). Although expensive, I tentatively plan for 2 * "Concorde "Sun Xtender PVX 1040T" (nominal max capacity of 104 Ah each.) When lowered, the 2619 shell prevents taller or wider batteries in this location.
Are there other batteries which I should consider with the 2619?
Panels And Charge Controller:
If I use 100W panels and assume near-perfect weather conditions (4.5 hrs per day, 77% net efficiency SWAG from the "Icarus calculation") the each panel yields a bit less than 350 WH. I need 3 of them in perfect conditions. 4 would be more realistic, and support some daytime electrical usage simultaneousl with charging the batteries. In an ultra-cheap PWM configuration, 4x100W Panels + Controller costs about $700.
Or, I could spend about $1100 and get a really high-end MPPT controller, allowing use of 24 Volt panels instead (2 * 240W). That's more like 5* 100W "12V" panels, providing a generous amount of extra power for daytime use (running an air cleaner; playing the Stereo, and etc.)
I'm inclined to blow the money - it's "like" getting a 5th 100W panel included (cutting the "effective price difference" to just $350). It simplifies the wiring and mounting a lot (less wire and connectors saves some money as well); It looks WAY better, leaving the roof a lot less crowded.... And it gives much better battery management.
Those components would be something like:
2 Suniva MVx240-60-5-501
http://www.suniva.com/documents/MV%2...%2002%2028.pdf for about $580
and the Morningstar Tristar MPPT-60 for about $520. (Why not the 40A? Because the 60A includes the Ethernet Web Interface, for use with my $35 Raspberry Pi computer.)
Comments? Thanks in advance.