[rickst29]

Originally Posted by ShrimpBurrito

First of all, if you replace your interior lights with LEDs, you can reduce your power requirements for light to virtually zero -- my LEDs generate at least as much light, and draw only 10% of the power (about 150 mA, IIRC). The ones I have plug into the existing sockets, are circuit boards that shine only downward, and require no retrofitting.

Dave, do you remember where you bought these things? I realize that your Trailer might be in storage, so I'm not going to be if your answer is "not sure, and can't look..."

Originally Posted by ShrimpBurrito

And since lighting represents a major part of your power requirements, I would do that first. Assuming most of the "bathroom etc." visit power requirements are also lights, your 280Wh drops to 28Wh, which at 12VDC is only 2.3Ah. That's nothing.

Indeed, the lighting load becomes insignificant.

Originally Posted by ShrimpBurrito

Additionally, look at the "brick" that supplies the power to your CPAP, and perhaps the jack on the machine where the power supply plugs into, and you may find that your CPAP machine runs on 12VDC.

Bravo, it is 12V! At 60W, I'm not sure that I want to go through a cigarette adapter - but there are many other kinds of plug/socket pairs which could hold together tighter, and provide higher current capacity too. (IIRC, TM's own cigarette lighter sockets are fused pretty low, at either 3 or 5 Amps each.)

Originally Posted by ShrimpBurrito

I have 2 Trojan T-105s (total combined capacity of ~220Ah), and while camping with a guest that ran a CPAP.... And they are half the price of AGMs last time I checked.

I looked at them, but they are too tall and too wide for the 2619 A-frame. (Between the propane tanks and the front shell in "down" position, there's no room in either of these directions. The only direction with any room for increased battery size is the "length" along the rectangular base.)

They also aren't very well tuned for accepting the fast, high-current solar charging process: In the Trojan lineup, the 24-AGM would be the correct battery for deep-cycle solar, and that Product lies in a nearly identical (and much less attractive) "Ah per dollar" as my Concorde choice. (The 1040T is about 20% "more" battery, in weight and capacity, at about 20% more cost.) them. It's about taking in the high charge current without overheating - not about "maintenance free".

Great post, you nailed it on the 12V CPAP. But I have another big consumer, which I didn't mention: The fridge. This is somewhat "optional" but very desirable functionality:

My Norcold is re-wired, so that 12V operation is independent of the Norcold's own "mode selector" switch. As you know, the "thermostat" dial is basically a direct connect into the propane needle valve -- if you set the dial to a high enough value (e.g. 5 or 6 ) to keep the Fridge cool in the early evening, your beer, lettuce, milk and everything else freezes by just before dawn -- when the ambient temperature is much lower, and your setting is now far too "strong".

I don't like wilted lettuce, or frozen milk. And exploded beer, that's simply TRAGIC.

In powered camping sites, I run the fridge on 120V all the time. (Like the new 12V circuit, this is now controlled by a PT100 thermocouple, we just set the Norcold temp control to "6" and let the PID turn off the power when the temp approaches 34). But in the Boonies, we will want to use propane at a relatively low-power "don't freeze in the morning" dial setting, with DC electric adding heat to make up for the "too low in the early night" propane flame. (Adding electric heat, according to PID and thermocouple rules.)

That will probably be at least 2 hours @ 120W, another 240Wh -- so I just ate up most of the savings which you created by switching to LED lights. But your ideas allow the same config(s) to run MORE STUFF, I'm thrilled!