Adding Generator Support - Should I use a Battery Charger or Inverter Based Gen Support

Hi all,

Was hoping somebody here could give me a little guidance. I've done a lot of research, but need to fill the gaps a little.

I'm looking to put together a small mobile solar, generator assisted power system.

At present, my design looks like this:

Capacity - 2880Wh (generally a little lower than this, but I like safety margins)
Batteries: 450Ah (20-Hour Rate) @ 24V AGM
PV: 1.5kW (6 x 250W)
Charge Controller: Midnite Solar MPPT 60A

No Inverter - DC Loads only

Now, provided my numbers don't look too silly, my next task is to determine the best way to supply generator support, as it MUST also be automated.

My intention is to apply a bulk charge on mornings where solar insolation drops below 3 hours for more than a day (which is rare), just to keep the batteries freshened up (then let the PV panels take care of adsorption during the day). This is only for the winter months, temps are relatively warm and sun hours will approach 5+ in peak season. The system needs to be failsafe!

I'm not sure how to best go about interfacing a generator. I could use a 24V 50 or 60A battery charger with inbuilt PF correction and connect to a 3+ kVA generator (with auto-start), and an additional autostart controller or I could use an inverter with inbuilt generator support.

As far as I can tell, the inverter will incur power losses when its just sitting idle - am I right about this? I like the idea of the inverter option due to its autostart capabilities though. I don't have any need for AC at the site, so an inverter is otherwise surplus to requirement.

What would you do? If you did use a battery charger (instead of inverter), what would you use? How would you control the autostart?

I don't mind spending money on a decent solution, it has to be reliable. Ideally I would also like something with remote Ethernet diagnostics (but now I'm just being picky :) )

Would love to hear your thoughts!

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